gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Well, OK, after years of drooling over Optical Craftsmen scopes as a kid, and owning one, I now can report the following data. I had three OC mirrors: one was really badly astigmatic, a 4.25" F/10. Another is excellent, rivals my 4" apo, 4.25" f/10. And the third--well you can see the Foucault in the pic below. It was badly annealed. We had some hope that the rilles were in the coatings but after the coatings were stripped they were still very much, totally, 100% there.
So my advice is: if you're offered an Optical Craftsmen telescope throw it on a Foucault and star test it first. The biggest rille did show on an out of focus star test. Don't pay much money for OC optics: Let's say that 2/3 is bad luck, and say 1/4 OC mirrors are in fact this bad. That's still a big chance of a defective mirror. I think these guys must have only spot checked their product line: hard to see how this mirror made it out the door.
Anyhow I've got an OMI mirror on the way, by coincidence the every-more-rare f/6 ten inch came up as I was doing this project, so I will get out of this with a very nice telescope at reasonable cost.
And I have to eat my hat: Rod said he'd seen a few "soft" OCs compared to Caves and I have to believe that Cave had better qc/qa than OC at this point. When OC was on its game it was very very good. But this kind of thing is nonsense, shame on Dick Nelson:
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Greg:
Does this mirror have that pebbly-textured back that was typical of OC mirrors? I wonder where Dick Nelson got his blanks, as I don't think I've seen those mirrors in anything else.
My 8" f/6 OC mirror that's in my Springfield now has an excellent mirror. So they certainly weren't all bad.
I agree, must be the annealing. I can't imagine how you could polish that kind of surface into a mirror! I'd imagine that the mirror is junk, then, as if you refigured it, it would change the stresses and perhaps deform again?
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Greg:
I agree, must be the annealing. I can't imagine how you could polish that kind of surface into a mirror! I'd imagine that the mirror is junk, then, as if you refigured it, it would change the stresses and perhaps deform again?
-Tim.
Well I have purchased a 10" f/6 OMI mirror that's never been used. I think throwing money at the mirror in the original post would be a pure waste of time. One person advises me off list to mask off the *BLEEP* parts and use as is.
My thought: why waste good tape?
If we count your 1 mirror and my 3, that is a 50% s-u-x rate. I just don't see how OC could have let this out the door if they'd had any qc/qa measures in place.
I think IC did make good mirrors. I own one, so do you. But they are a bad "bet". If you come across one in a barn somewhere, try to get it, it might be sweet indeed, but try to get it cheap.
The basic iron that goes with this scope seems OK now that I have a good mirror on the way (may it arrive safely). I'm not really sure I want/need a Newtonian, but for sure it will be easier to resell with a working mirror.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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I'll keep watching to see what you decide to do with the scope, then.
You must have bought the OMI mirror on the 'mart? That's what I would have done.
If the problem with the OC mirror was due to poor annealing, it might have been okay going out the door, and might not have turned sour for years after.
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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CHASLX200
Carpal Tunnel
Reged: 09/29/07
Posts: 2097
Loc: Tampa area Florida
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I wonder if that is the same 10" F/6 OMI i was gonna buy in FL? The OMI should be super, as all of my OMI's have been great.
Chas
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deSitter
Post Laureate
Reged: 12/09/04
Posts: 3338
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Jeez that is just horrifying! I've never seen anything like it. I'll bet the glass would shatter like a pinata if struck hard. That's not even a candidate for re-figuring.
-drl
Quote:
Well, OK, after years of drooling over Optical Craftsmen scopes as a kid, and owning one, I now can report the following data. I had three OC mirrors: one was really badly astigmatic, a 4.25" F/10. Another is excellent, rivals my 4" apo, 4.25" f/10. And the third--well you can see the Foucault in the pic below. It was badly annealed. We had some hope that the rilles were in the coatings but after the coatings were stripped they were still very much, totally, 100% there.
So my advice is: if you're offered an Optical Craftsmen telescope throw it on a Foucault and star test it first. The biggest rille did show on an out of focus star test. Don't pay much money for OC optics: Let's say that 2/3 is bad luck, and say 1/4 OC mirrors are in fact this bad. That's still a big chance of a defective mirror. I think these guys must have only spot checked their product line: hard to see how this mirror made it out the door.
Anyhow I've got an OMI mirror on the way, by coincidence the every-more-rare f/6 ten inch came up as I was doing this project, so I will get out of this with a very nice telescope at reasonable cost.
And I have to eat my hat: Rod said he'd seen a few "soft" OCs compared to Caves and I have to believe that Cave had better qc/qa than OC at this point. When OC was on its game it was very very good. But this kind of thing is nonsense, shame on Dick Nelson:
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
I'll keep watching to see what you decide to do with the scope, then.
You must have bought the OMI mirror on the 'mart? That's what I would have done.
If the problem with the OC mirror was due to poor annealing, it might have been okay going out the door, and might not have turned sour for years after.
-Tim.
Yeah I got the OMI mirror on the 'mart. Might even be here thursday. Something weird going on with the 'mart. Herb York is no longer running the operation and a lot of us aren't getting our emails in response to our ads. He had written me and I had written him, but neither of us saw an email from one another till I looked him up by name and telephoned him.
I must say that the word I used that got bleeped is not a profane word. My 1936 Webster's has a number of different entries for cr-p and this dictionary, well reputed as a literary dictionary, did not go into the vulgarisms that would appropriately be bleeped. Cr-p in the sense that I was using it probably dates back to the medieval usages: "residues from rendered fat" and "sediments or dregs of beer or ale." Craps games is common and accepted usage. It also used to mean "the gallows." When we say "pigeon cr-p" we are in fact using a polite euphemism so as to avoid saying pigeon s---.
ANYHOW, I researched that after my elementary school teacher said it was an OK word to use in the class room. Which shocked me. That was longer ago than I care to admit, but you already know that I was drooling over Optical Craftsmen at the age of 10. I think the moderators ought to rethink that one. (I hope I didn't use some stronger term; I think not, I am well trained).
Well: some old optics survive and some do not. I think that people who lay out good money for older optics are well advised to buy from people they know and probably to negotiate terms, such as, $300 if the mirror comes back from coating in good shape, and $150 if the mirror comes back in bad shape. Or its your mirror you get it coated and I'll pay you $450 for it with new coatings--if it's still in good shape.
Anyhow I got a good deal even with the bad mirror and the OMI mirror was very well priced. The OMI mirror has 60.85 inches of focal length versus 61.25 for the Optical Craftsmen it is replacing. So I am going to need to *go lower* and will have to get a low profile focuser.
The flotation mirror cell also has some adjustable bolts with springs on the back and I can use those to push it in at least 1/4, and probably 1/2 inch. So odds are high I can outfit this OTA with a moonlite low profile and everything will come to focus.
The fiberglass tube "as is" was pre-drilled for a two inch focuser but fitted with a 1.25 as the "bargain" model. The spider and secondary are also 2" sized.
I can if I choose mess around with the mount and I can also stick it somewhere against the day when I resell everything, but I have to say that the thought of putting the AP900 on the Optical Craftsmen pier is much more attractive than using the old OC. For one thing I will ahve much better control over the optical tube, and zero backlash.
As currently constituted without coatings the scope has 4% reflectivity and could be used as a moon scope with effectively a two inch aperture for light gathering but ten inch resolution. But I think that the OC mirror is going to hold coffee pots. Until it totally fractures and I throw it out.
regards
Greg N
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"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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Lew Chilton
Pooh-Bah
Reged: 10/20/05
Posts: 1139
Loc: SoCal
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Greg,
I commented on your 10-inch OC mirror on the AM forum, so I won't repeat here. If the Enceladus-like fissures on your mirror were magically removed, the surface actually looks pretty smooth, although the shadows look a little too weak for an f/6, i.e., undercorrected. I don't think the optician would have bothered putting any effort into parabolizing this mirror had he seen these flaws on the foucault tester.
-Lew
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I don't get no respect, but my scopes do! 
----------------------------------------------
1961 Swift 60mm model 839 (2); 2003 TV-102/GM-8; 1959 8" f/6 Treckerscope; 1959 8" f/7.4 Murray Scope; 1959 Fecker Celestar-4; 1978 4" Edmund Astroscan; c. 1986 4-inch Celestron-Vixen SP-C102; c. 1950 20X60 Saturn spotting scope; 1963 7X50 Nippon Kogaku binoculars; Unitron #114 alt-az mount (Swifty-tron)
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Greg,
I commented on your 10-inch OC mirror on the AM forum, so I won't repeat here. If the Enceladus-like fissures on your mirror were magically removed, the surface actually looks pretty smooth, although the shadows look a little too weak for an f/6, i.e., undercorrected. I don't think the optician would have bothered putting any effort into parabolizing this mirror had he seen these flaws on the foucault tester.
-Lew
Well I'm wondering whether this thing was ever ON a Foucault tester but I see your point. I have been told that I could just tape up the mirror. If I were in dire straits I would do that. But the OMI mirror was just sitting there....
My 1977 OC 4.25 inch is a very good mirror so I won't say they wuz all bad at that shop. But I do think that if you're buying an OC that sort of appears at random (as this one did) there is some need for caution.
It sort of reminds me of the story: two economists are walking together and one spies a $20 bill. "Leave it there, says one to the other. "If it was real it would already have been picked up." (a joke about the efficient market hypothesis).
I'm have willing to believe that all the good remaining OC optics are in the hands of people who've scooped them up...better odds with a new reputable dealer.
thanks for taking the time to post your comments,
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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rmollise
Postmaster
Reged: 07/06/07
Posts: 5323
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Well, yeah, Greg...I hate to say "I told you so," but shenanigans like this were the reason for my original comment that OC warn't no Cave. 
I hate to say it because this would have been an impressive telescope otherwise, and maybe still will be with a replacement mirror.
Not the first hideous mirror I've seen in one of their scopes.
--------------------
Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
Edited by rmollise (11/03/09 07:40 AM)
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Jeez that is just horrifying! I've never seen anything like it. I'll bet the glass would shatter like a pinata if struck hard. That's not even a candidate for re-figuring.
-drl
Correct on all counts. The mirror is, however, a candidate for door stop for the door to my screened in porch. I don't know if it is high enough, but I think it will do the trick. No one else I know has seen anything like it either.
If you masked the valleys it might work out to a reasonable 8 or 9 inch mirror: the underlying curve is OK. But I'm taking this mirror out of circulation. Enough of this evil glass.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Not the first hideous mirror I've seen in one of their scopes.
It would be of interest to me Rod if you could struggle to recollect how many OCs you've seen that were good and how many were even half as bad as this one. I'm trying to get a handle on the statistical probability of getting a good one.
The urge to own OC seems to be evaporating. Nutha' childhood dream up in smoke.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
I wonder if that is the same 10" F/6 OMI i was gonna buy in FL? The OMI should be super, as all of my OMI's have been great.
Chas
Well I don't know why you didn't go for it, but I'm glad I got to it before you, as I have an optics-less setup that will be functional once it gets here. OMI does have a good reputation.
But then again, so did Optical Craftsmen....
I wonder if OC used some kind of proprietary annealing process which allowed half of their mirrors to self destruct after Dick Nelson passed on.
I actually went to OC's shop in Northridge in 1965 to pick out my 4.25. I thought I was in heaven.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Well, yeah, Greg...I hate to say "I told you so," but shenanigans like this were the reason for my original comment that OC warn't no Cave.
I hate to say it because this would have been an impressive telescope otherwise, and maybe still will be with a replacement mirror.
Not the first hideous mirror I've seen in one of their scopes.
I forgot to add: the crunching sound you here in the background is me chewing on my hat. At least in the future we've got this thread here so any time the subject of OC comes up in this forum or elsewhere people can point to some of the OC perils.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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deSitter
Post Laureate
Reged: 12/09/04
Posts: 3338
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Quote:
Quote:
Jeez that is just horrifying! I've never seen anything like it. I'll bet the glass would shatter like a pinata if struck hard. That's not even a candidate for re-figuring.
-drl
Correct on all counts. The mirror is, however, a candidate for door stop for the door to my screened in porch. I don't know if it is high enough, but I think it will do the trick. No one else I know has seen anything like it either.
If you masked the valleys it might work out to a reasonable 8 or 9 inch mirror: the underlying curve is OK. But I'm taking this mirror out of circulation. Enough of this evil glass.
Greg N
Would make a good hors d'oeuvres tray. The olives will all roll to the middle, unless they get stuck in a rut 
Consider this an opportunity to install a conical mirror!
-drl
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rmollise
Postmaster
Reged: 07/06/07
Posts: 5323
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Quote:
It would be of interest to me Rod if you could struggle to recollect how many OCs you've seen that were good and how many were even half as bad as this one. I'm trying to get a handle on the statistical probability of getting a good one.
The urge to own OC seems to be evaporating. Nutha' childhood dream up in smoke.
Greg N
I'd hate to hazard a guess, since we are talking about "over the last 40 years." Frankly, in my recollection, about 50 - 50...but the number I've used over the last four decades is still too small to be very significant statistically, I reckon.
--------------------
Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Greg:
We'd all love to see pics of the scope! ...because if you're replacing the mirror with an OMI, your "dream" (likely based on drooling over catalog photos, like I did) can still come true!
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Greg:
We'd all love to see pics of the scope! ...because if you're replacing the mirror with an OMI, your "dream" (likely based on drooling over catalog photos, like I did) can still come true!
-Tim.
Well in due time. I want to take some pics of the scope as is and as refurbished. I think the creamy Optical Craftsman fiberglass OTA will look very nice on top of an
AP mount. That's where I'm headed directionally. I may keep the original EQ mount "for the day I resell everything together" or see if there are any offers now.
I think that even if I break up the EQ part from the rest of the configuration, that once I have an adapter on the OC pier that will hold the AP900, that there are enough aperture starved AP mount/refractor owners out there who would pop for the pier/tube combo and use their own AP. Or maybe I could sell it complete with QMD and get the AP go-to. I'd have to have some significant extra bux though, and everything directionally says that isn't going to happen.
I think DRL was saying that I should get a conical mirror. I have given some thought to that but it seems to me to add unnecessary complexity. First off, the conical mirror is $850, the one I just bought was $400. Second, and this equally important, the conical mirror weighs 30% less. Y'all saying of course that's the point. Well that's the point for a Dob person. From my point of view, the heavier the behind of this scope, the higher it rides in the saddle, and the more zenith clearance I have at the bottom. So I am not anxious to lighten the rear load.
Then y'all say well you can add back some mass. Which I can. But if I add back mass it too will have thermal properties. You either want the mass or you don't. What I think I'd like to do is experiment with some fans designed to break the thermal boundary on the mirror. These would be internally mounted on the mirror cell and would not involve cutting holes. We've talked about them on C14. I would like to get two or three of these fans, which are almost wafer thin, and use this opportunity to play with them as a prototype experiment for the C14. The idea we kicked around on C14 was internal installation of fans designed to break the mirror boundary layer but not mess with external air on the assumption that you lose the advantage of sealed optics protection that way.
Given how well some C14 mirrors are holding out compared to the pinholes on the Optical Craftsman (that pic is posted on Astromart in Equiptment section) I think that the sealed optical design has some merits.
I guess I'll see if I can download the picture from the 'mart and upload it here, but I'll have to resize, what a pain.
regards
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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This is what a 41 year old mirror looks like when it has not been sealed from the elements. At the top you can plainly see that the rille which is shown vertically in the foucault pic is plainly evident in the erosion pattern of the coatings. It is unclear as to why this should be. In any case the illumination is not 100% behind the full ten inches we did the best we could with the lighting at hand. In high resolution its more impressive but this is good enough. An old timer admitted that this mirror was "getting on the worse side" of the bad mirrors he's seen. In this pic it really looks like a coating issue, so I was quite dismayed when the rilles were so evident without the coating. The no-coating foucault pic looks identical to the with-coating foucault. No point in posting it. This was not a coating issue. But the rille did impact the coating.
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
No point in posting it. This was not a coating issue. But the rille did impact the coating.
And I will say, this is one of the reasons why, if you have an open tube Newt, it's probably good idea to get new coatings every five or ten years!
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Hard to imagine how a defect in the annealing could show up in the coating picture above. Could it be a shadow of a defect within the glass? If so, you should be able to see it now that the coating has been removed (and assuming that the back of the mirror is "pebbly textured" like the OC mirror I have and others I've seen.
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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We were unable to get a visual on any crack. We did see some striations on the rear that looked roughly parallel to the markings on the front and took a few pictures, which I'll post when my partner in this affair (on the working part, I'm the pocketbook) Bob M uploads them and sends them to me.
To the naked eye this mirror looks smoother than a baby's fanny. Maybe with polarized light something will be visible as has been suggested here (or AM, I forget which).
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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Lew Chilton
Pooh-Bah
Reged: 10/20/05
Posts: 1139
Loc: SoCal
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Hi again, Greg.
Despite the flawed surface of your OC mirror, did you ever actually observe thru it? I sure would be curious to know how it star tests and performs on, say, Jupiter or the moon. Even w.o. a coating, you can do this.
If you get the chance, give us a report.
-Lew
--------------------
I don't get no respect, but my scopes do!
----------------------------------------------
1961 Swift 60mm model 839 (2); 2003 TV-102/GM-8; 1959 8" f/6 Treckerscope; 1959 8" f/7.4 Murray Scope; 1959 Fecker Celestar-4; 1978 4" Edmund Astroscan; c. 1986 4-inch Celestron-Vixen SP-C102; c. 1950 20X60 Saturn spotting scope; 1963 7X50 Nippon Kogaku binoculars; Unitron #114 alt-az mount (Swifty-tron)
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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The view of Jupiter was pretty good, but to assess the view relative to the seeing one needs repeated observations. I could distinguish the notch of the GRS and the GRS itself, the bands were clearly divided with some detail inside them. But just *how* good? Hard to say because you can see those details in a 4" refractor or a good 4.25 inch Newt.
Star tests showed a bump or tear drop shape on one side of the star in focus, and the biggest rille on the Foucault showed as a heavy black line across the diffraction rings of the out of focus star.
The bump on in-focus stars also showed on Jupiter's moons and if you looked very carefully you could see that Jupiter itself had a kind of partial doubling of the image in the same direction as the tear drops on the stars and moons. But it took awhile to see that faint aberration.
So what can I say--the scope was usable but anyone who has used good scopes would find the imperfections annoying. And if I had recoated the mirror the imperfections might have gotten worse (more light to make tear drops).
I did look at the moon and the view was pretty good. I find the moon useless as scope testing mechanism. I can't tell you how many times I've heard "100x per inch on the moon with no image break down!" yeah well. It might be that one can side by side several scopes on the moon and detect differences if they all zero in on the same spot; but if you just swing a scope on the moon the odds are it's going to be "dazzling."
I actually posted a drawing of the inside-of-focus, outside-of-focus, and tear drop aberration in-focus on astromart.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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JamesE
impetuous lurker
Reged: 10/22/07
Posts: 1295
Loc: Westbank, BC, Canada
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Hi Greg,
For what it's worth, your troubles with the mirror and the openess (or frankness) you are displaying with it's problems is fantastic information for someone like myself. Even though it 'sux' for you, I personally appreciate how all this information is presented.
Cheers,
--------------------
James
(Thanks to Attilla for the Clear Sky charts)
Current Projects : Tasco 15TEA - 3 inch pier mounted planetary scope
Priorities : Wife, Kids
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Bill Griffith
member
Reged: 08/12/09
Posts: 30
Loc: Ca.
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Ditto James.
Thanks to all, I'm getting a great education on this forum.
Mr. Provin can you shed any info on how booles of glass came into O.C.
The old catalogs really were specific in the testing, Which convinced me to they knew what they were doing.Sodium line appox.5870 A if memory serves a good middle of the road in the visible spectrum. A definition of reflectness not reflectivity. Talk the talk and not walk the walk.
Anyway I'm taking my 10" F6 O.C. primary out and will test and report back.
I've flowed a fair amount of borosilicate, ULE , Zerodur and fused silicate and have only seen something like this in bad seal planes striations with air bubbles this is a bad density issue!
Thanks Bill
Greg can I buy the mirror send me a p.m. if you want
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Bill Griffith
member
Reged: 08/12/09
Posts: 30
Loc: Ca.
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Ditto James.
Thanks to all, I'm getting a great education on this forum.
Mr. Provin can you shed any info on how booles of glass came into O.C.
The old catalogs really were specific in the testing, Which convinced me to they knew what they were doing.Sodium line appox.5870 A if memory serves a good middle of the road in the visible spectrum. A definition of reflectness not reflectivity. Talk the talk and not walk the walk.
Anyway I'm taking my 10" F6 O.C. primary out and will test and report back.
I've flowed a fair amount of borosilicate, ULE , Zerodur and fused silicate and have only seen something like this in bad seal planes striations with air bubbles this is a bad density issue!
Thanks Bill
Greg can I buy the mirror send me a p.m. if you want
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Ditto James.
Thanks to all, I'm getting a great education on this forum.
Mr. Provin can you shed any info on how booles of glass came into O.C.
The old catalogs really were specific in the testing, Which convinced me to they knew what they were doing.Sodium line appox.5870 A if memory serves a good middle of the road in the visible spectrum. A definition of reflectness not reflectivity. Talk the talk and not walk the walk.
Anyway I'm taking my 10" F6 O.C. primary out and will test and report back.
I've flowed a fair amount of borosilicate, ULE , Zerodur and fused silicate and have only seen something like this in bad seal planes striations with air bubbles this is a bad density issue!
Thanks Bill
Greg can I buy the mirror send me a p.m. if you want
Good lord man what are you going to do with it? Maybe I should auction it on Astromart as the worst mirror ever.
You know, I might do that. There are people in the business who might pay for this mirror simply because you can't MAKE a mirror like this!
I don't know though, I was really keen on the door stop...
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Here. I'll give y'all my hand drawings of the original Foucault (before we put the Foucault on a TV camera and got pictures), and my crude impressions of the diffraction patterns inside and outside of focus, as well as what it looked in focus.
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Now what I want y'all to understand about the diffraction circles is that if I could draw worth a damn they would be perfectly circular. I just can't draw a circle. So imagine them circular and imagine it collimated with the black dot perfectly lined up dead center. We know how to do that.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Once again, I can't imagine a mirror being figured with a defect like that in it. Had to have "relaxed" into that shape after it had been figured. The concentric rings "behind" the defects suggest that the mirror was pretty good, initially.
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Once again, I can't imagine a mirror being figured with a defect like that in it. Had to have "relaxed" into that shape after it had been figured. The concentric rings "behind" the defects suggest that the mirror was pretty good, initially.
-Tim.
Well let's say Dick Nelson is out somewhere to bid a contract and he's got some kid watching some kind of automated thingy that's turning out eight mirrors. And the kid is one of those 60s types who ducks out to smoke a bit of weed.
Two days later the boss comes back and says did you finsih the mirrors and the kid says sure did boss here they are aluminized and everything and he says that's fine box 'em and ship 'em.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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That would have produced zones or roughness to the figure. Your mirror looks like a combination of two totally different and independently-caused things.
Number a: A smooth figure.
Letter 2: A map of the Grand Canyon, viewed from orbit!
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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deSitter
Post Laureate
Reged: 12/09/04
Posts: 3338
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Rofl - Valles Craftsmaneris!
-drl
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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I did extensive Internet research last night and finally found an authenticated picture of the proprietary grits that Optical Craftsmen used to make my 10" f/6 mirror. The links takes you to a picture.
http://tinyurl.com/yrkuwb
thanks,
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Cute!
...but not particularly helpful.
I wish that Robert Provin would chime in here. He worked at OC, and would know best what may or may not have gone on there.
Greg, I have to ask: Is there some deep-seated need here to vilify the opticians at the late Optical Craftsmen? I, for one, have a mirror I'm VERY happy with from them, that was handed to me by Dick Nelson himself before he went out of business in 1972. I remember not being very courteous to him when I picked up the scope, because he'd not been answering his phone for months on end and had most of my money for it, but he was very polite to me as he helped me load the scope into my dad's van.
I distinctly remember him saying "doesn't look like it's going to be a good night for seeing" because the Santa Ana winds were blowing. But when I got home and set the scope up, I got probably one of the best views of Saturn I've ever had visually through any telescope.
I think it's interesting trying to track down the source of the problem with your mirror (a truly fascinating puzzle), but I also think it's clearly not representative of OC optics.
...if you hate this scope so much, why not sell it? (hint, hint!)...
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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deSitter
Post Laureate
Reged: 12/09/04
Posts: 3338
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I don't know much about glass but is there any chance this mirror has "flowed" so to speak over the years, and that the worst is behind it? Maybe a good idea would be to try to get it into a good sphere first, and let it sit for a year.
-drl
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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drl:
It's probable that it wasn't fully annealed when it was ground and figured, such that it changed shape over the years since.
But that's not the same as "flowing". Many people attribute wavy old windows to glass being a "slow liquid", but that's not the case. Glass is an amorphous solid. I live in a Victorian house with wavy window glass. It's like that because they didn't have "float glass" technology in those days. Windows were made by blowing glass into cylinders that were cut longitudinally and laid flat to anneal.
...some of which were also not well annealed. I was repairing one of our window frames several years ago, and had to remove the glass. Got all the putty out and carefully tilted the glass out of the frame. But when I picked it up with my hands on either side, it shattered!
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Cute!
...but not particularly helpful.
uld chime in here.
I think it's interesting trying to track down the source of the problem with your mirror (a truly fascinating puzzle), but I also think it's clearly not representative of OC optics.
...if you hate this scope so much, why not sell it? (hint, hint!)...
-Tim.
My 4.25 inch f/10 mirror from Optical Craftsmen was also a dawg. That was the scope my Mom bought for me in Xmas 1965 and it was quite a prize. Decades later I looked it over and it too was a dawg, but not like this mirror. It was severely astigmatic. Not a little bit. A plain oval that rotated when you turned the mirror. I found another OC mirror from the late 70s and it is quite good (4.25" f/10).
I don't think that *all* their mirrors were bad. I think about half of them were. And 50% leaves me with a low opinion of shop standards. I can't speak to the good ones because they seem to be hard to come by. But my 4.25" f/10 (from 1977) is parabolized and it gives very sharp views of Jupiter. When I was a kid, I assumed I couldn't see the red spot because I didn't have a big enough scope. Now I know that it was because the mirror was junk. If the scope under the Xmas tree in 1965 had been of the same quality as the 1977 mirror, the hours I spent back in the 1960s watching Jupiter would have been much more rewarding. For one thing, I would have had a view of the Jupiter's rotation. All I saw were two vanilla bands. And that's a shame, because adjusted for inflation a $200 scope was north of $1,000 in those days. Mom went all out. That scope did no better than my son's $170 Star Blast on Jupiter. For north of $1k a 4.25 inch mirror should give a four inch apo a run for its money: which the 1977 mirror does indeed do.
I'm considering what my plans are with the ten inch OTA. I am going to get it a new mirror--the current mirror is unsellable unless someone is so curious they just have to have it. But by the time it is refigured it is no longer an OC mirror. It is an OC blank that was refigured.
The rest of the hardware will probably sell with a good mirror inside though I don't know whether the sentimentalists out there will want OC iron with OMI or Lightbridge optics. Actually, based on my experiences, that's about the ONLY way I would buy an OC at this point: with someone else's mirror.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Greg:
I won't speak for other collectors, but what about this option?
Put the OMI mirror in a modern OTA (probably cork-lined aluminum is the best, thermally) with parallax rings and a dovetail for mounting it on your AP mount. Sell off the entire OC telescope to a collector, bad mirror and all, and let the collector either refigure that mirror or find a replacement OC mirror (tested before buying, perhaps).
These old scopes don't show up all that often anymore, and there are still, unfortunately, people parting the remaining ones out. You might be able to maximize your money by doing that, but over the long haul it will be more valuable kept intact than parted out.
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Greg:
I won't speak for other collectors, but what about this option?
Put the OMI mirror in a modern OTA (probably cork-lined aluminum is the best, thermally) with parallax rings and a dovetail for mounting it on your AP mount. Sell off the entire OC telescope to a collector, bad mirror and all, and let the collector either refigure that mirror or find a replacement OC mirror (tested before buying, perhaps).
These old scopes don't show up all that often anymore, and there are still, unfortunately, people parting the remaining ones out. You might be able to maximize your money by doing that, but over the long haul it will be more valuable kept intact than parted out.
-Tim.
That might work. I don't need to part it out really. The only thing that is "on the block" potentially is the German equatorial mount. The pier I would get an adapter for. I can stash the GEM & counterweight and then resell the entire set (OEM and what I put on) at my leisure.
The OEM focuser needs to be fixed or replaced; the "best fit" would be a Parks Optical two inch, which would have the feel and look of a 1960s era two inch. But I'm goign to put on a moonlite.
I don't think that the OC mirror can be restored. Someone could try of course, but I guess folks who are intrigued by this scope will want to see the full photo essay so I'll have to put everything up on Astromart.
But let's say I put the german equatorial in the closet and use the pier with an adapter for the AP900, use the original rings, and add a focuser. When I resell I can make the entire original set available PLUS there will be this neat adapter for someone who wants the advantage of a more modern mount.
If one were to be successful refiguring the mirror, one is not out of the woods. One of the dirty secrets of the Newt biz is that f/6 (or any other ratio) is not really f/6. The Optical Craftsmen is f/6 and true fl of 61.25 inches. An OMI mirror that I will probably end up using is 60.85 inches. Another mirror that I have been discussing (Lightbridge) is 59.5 inches. I'm thinking about that (I'd have to resell the mirror that I just purchased). If the mirror's real focal length is not pretty close to the original, we're looking at moving the mirror cell and messing up the pretty tube.
Since I *have* this thing and am basically at this point a pier adapter and a focuser away from having a fine Newt, it is well suited to see whether a 10" GEM Newt adds anything to my life. My 2c is that if I am really enamored of this aperture I should just get a 9.25 and use it on my Losmandy/Berlebach. But I've been doing this hobby for a while and "nice Newtonian with some aperture" has not been in my repertoire. So I might as well give it a go. But I will also put it up on Astromart as if the price is right I would just ship it out. But I would like to get it up and running to see how it feels. There are very few f/6 10" GEM mounted Newts out there, Sue French uses one and it's a great scope, but that's the only one I know of.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Tim I'm confused by your claim OC went out of biz in 1972. I seem to recall looking at their OTAs while in college (wanted an 8 inch) and deciding they were too expensive. The history I got was they went out of business in 1977 or thereabouts. I have a 1977 vintage OC mirror. I think it's marked on the back but haven't looked lately.
I'm hazy on the details but I seem to remember that this business "wound down slowly" over a period of four or five years. Maybe they just continued to sell off inventory over that time? GN
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
|
tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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I think they went out of business, tried to make a comeback sometime in 1973 or 1974 (I think the ads even said "OC is back!"), and disappeared finally around the time you say.
When I picked up my scope in Spring of 72, Dick Nelson was the only one there smack dab in the middle of the day (and it wasn't lunchtime either, probably 2 or 3pm). I was annoyed with him because I'd been promised a 7.5 week ready to pickup time, and it took 7 and a half months. During the last 2 months or so, I was literally calling him every day, and nobody picked up the phone or it would always be busy. Finally, I asked the operator to "break in" when I got a busy signal, and was told that the phone must have been left off the hook.
It took me a few years to get over my annoyance over that, but I saw Dick at RTMC every year until he stopped going a year or so before he died. He was a decent sort and a true amateur astronomer, in the end.
I'm still maybe interested in your scope, but would need to have a ballpark idea of what you'd like to get for it, plus see pics to see what kind of condition it's in.
Pics would be cool for posterity here, no matter what you decide to do with it! (that was another one of them there "hints!"  )
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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rmollise
Postmaster
Reged: 07/06/07
Posts: 5323
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Quote:
Once again, I can't imagine a mirror being figured with a defect like that in it. Had to have "relaxed" into that shape after it had been figured. The concentric rings "behind" the defects suggest that the mirror was pretty good, initially.
-Tim.
Alas, likely not. I have little doubt this is the way this primary was from the BEGINNING. Yes, plenty of good, simple scopes came out of the 60s - 70s. Lots AND LOTS of dogs, too, and not all from who you'd think.
--------------------
Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Speaking of OCs...
A few years ago at RTMC, someone had an OC 8" Discoverer that literally looked like it had been painted with a mop. It was AWFul.
For hoots, I looked it over, though. Engraved in the decidedly non-OC mirror was "R. E. Brandt" and a date. I should have bought it based on that alone. I think he was only asking a couple hundred for the scope.
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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Robert Provin
professor emeritus
Reged: 08/14/06
Posts: 702
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OK guys, here's the dirt. The Optical Craftsmen turned out some *very good* mirrors and they turned out some real dogs! When Dick Brandt was the primary optician (I was working there for part of that time), so far as I know, all the mirrors were very good. Same goes for the very early mirrors. However, during my tenure (when Brandt was not there) I specifically remember Dick Nelson on a number of occasions giving the go-ahead to ship mirrors that everyone knew were bad (and I mean ugly bad!). Dick was a great guy, but he was a penny pincher when it came to the bottom line and he had little respect for the typical amateur's ability to tell a bad mirror from a good one. He didn't however let us kids work the mirrors when the big guys were out!
I never owned an Optical Craftsmen mirror myself, but I did respect the mounts and other mechanicals. All my scopes at the time had Cave mirrors mounted in an Optical Craftsmen tube and mounted on an Optical Craftsmen mount! I guess regarding the optics, it was sort of like working in a sausage factory, once you saw how it was made, you didn't want to eat one anymore! I owned 3 Cave mirrors and all were superb, which irritated Nelson to no end!
So there you have it. Bottom line: the mirror in question does not surprise me in the least!
Robert
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Hey Robert:
When was Brandt at OC? My mirror doesn't have any engravings on it, but it would have been made between about fall 1971 and Spring 72, when I picked it up.
I thought I was looking at something thrown together when I saw his name on the back of that mirror a few years ago. I didn't know he worked at OC.
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
OK guys, here's the dirt. The Optical Craftsmen turned out some *very good* mirrors and they turned out some real dogs! When Dick Brandt was the primary optician (I was working there for part of that time), so far as I know, all the mirrors were very good. Same goes for the very early mirrors. However, during my tenure (when Brandt was not there) I specifically remember Dick Nelson on a number of occasions giving the go-ahead to ship mirrors that everyone knew were bad (and I mean ugly bad!). Dick was a great guy, but he was a penny pincher when it came to the bottom line and he had little respect for the typical amateur's ability to tell a bad mirror from a good one. He didn't however let us kids work the mirrors when the big guys were out!
I never owned an Optical Craftsmen mirror myself, but I did respect the mounts and other mechanicals. All my scopes at the time had Cave mirrors mounted in an Optical Craftsmen tube and mounted on an Optical Craftsmen mount! I guess regarding the optics, it was sort of like working in a sausage factory, once you saw how it was made, you didn't want to eat one anymore! I owned 3 Cave mirrors and all were superb, which irritated Nelson to no end!
So there you have it. Bottom line: the mirror in question does not surprise me in the least!
Robert
Well, well, well. It pretty much had to be that way. All the evidence is there 40 years later in the product. Nelson was right of course. I couldn't tell at the age of ten that I was getting a sub-standard view of Jupiter.
I don't know what you do when you're mad at someone who's dead. File a karmic complaint?
Anyhow, thanks to the people who did take their crafts seriously, I have gotten to know what good scopes can do.
"Whatsoever thy hand findeth to do, do it with thy might; for there is no work, nor device, nor knowledge, nor wisdom, in the grave, whither thou goest."
So his legacy is a land strewn with his lousy scopes. And some good ones left behind by people who took their jobs seriously, and I guess, "did with all their might" the work that they could notwithstanding the indifference of the boss.
Greg N
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"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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Lew Chilton
Pooh-Bah
Reged: 10/20/05
Posts: 1139
Loc: SoCal
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Greg,
You seem to be trying awfully hard to demonize Dick Nelson. He was a very personable amateur astronomer who I think got in over his head after his scopes began selling like hotcakes and he was unable to keep up with demand. Profit margins were very small and large number of scopes had to go out the door for him to keep solvent. I agree that he shouldn't have allowed such bad mirrors to be sold. Had he followed Cave's example, he would have taken months or even years, in some cases, to fulfill orders rather than compromise quality, but in so doing making enemies of many buyers who were waiting for their scopes.
Business-wise, both men had their detractors, but personally, they were nice guys.
Coast Instrument was another company that couldn't keep up with demand and got in over its head, resulting in bankruptcy that left a whole passle of creditors and buyers holding the bag, including John Dieble (of Meade Instruments fame) and Tom Cave.
So either replace the mirror, which you said you were going to do, or sell the scope to Tim 53, then move on. Life is too short. 
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I don't get no respect, but my scopes do!
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1961 Swift 60mm model 839 (2); 2003 TV-102/GM-8; 1959 8" f/6 Treckerscope; 1959 8" f/7.4 Murray Scope; 1959 Fecker Celestar-4; 1978 4" Edmund Astroscan; c. 1986 4-inch Celestron-Vixen SP-C102; c. 1950 20X60 Saturn spotting scope; 1963 7X50 Nippon Kogaku binoculars; Unitron #114 alt-az mount (Swifty-tron)
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Pics would be cool for posterity here, no matter what you decide to do with it! (that was another one of them there "hints!" )
-Tim.
The scope is over at my friend Bob's house. I have to remember to take my camera over there. So long as a Foucault is involved in this project, the scope's staying at Bob's place. When I start messing with the mount, it will probably come home.
After reading the rest of the posts in this thread, I would feel a good deal less guilty about "breaking up" an OC. My Mom was divorced and on a single salary and had four kids and an alcoholic ex and she somehow found the bucks to buy me an Optical Craftsmen, which sold for round $200 back in the days when a VW bug cost $1k: and Dick is over there in Northridge chuckling at what losers we were to want his scope. I wrapped that 4.25 in a blanket and carried it around to various campgrounds all over California as if it were the ark of the covenant. I kept staring at those two vanilla bands on Jupiter hoping one day the seeing would steady to see the GRS and other details promised in the catalog, and the dark maria on Mars. And I carefully read the instructions and collimated the thing.
It was an astigmatic piece of junk. I was like Linus waiting for the Great Pumpkin.
It grates a bit. It also makes me appreciate Roland's devotion to quality even though he is aware, as Nelson once was, that the average person won't know the difference.
Well maybe that's not quite so true these days. I'll bet there are more Foucault testers and greater sophistication about star tests than back in the 1960s. I'd wager that many more folks know what they're getting than way back when film cameras couldn't reveal defects as fast as chip based optics will.
Jeeze whaddya guys think? Should I replace the secondary too? I was just going to get it recoated, but it might be some severely substandard OC optic.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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I will however grant the point about the hardware and the mount. The OC mount conditioned me to expect stability and good control over where I was pointing. When I first tried out the CG5 (the old one) and everything was jittering and the mount was bouncing I thought: what the *#%@! is going on here!
So, OC taught me the value of a good mount. There's a positive.
regards
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Greg,
So either replace the mirror, which you said you were going to do, or sell the scope to Tim 53, then move on. Life is too short.
Well I've got a new mirror here. It's quite pretty, and a good deal thinner than the OC. That's the day's good news! I'm going to throw it on the Foucault though and start test as well. Take nothing for granted is the new watch word...
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Greg:
I think your attributing malice where simple poor business sense would suffice.
I think all of these guys started out wanting to make a great product worthy of their names (or their made-up names, in the case of Meade Instruments).
Lew: I didn't know anything about Coast Instruments, but I'd sure like to find a nice Treckerscope one of these days! I certainly didn't know Diebel had a connection with them.
I do remember hearing stories of Cave cutting corners on optics, too, but those were from former Cave employees hired away by Diebel when he started producing Newts and made it his mission to put Cave out of business. ...and when he'd done that, he went after Celestron.
When I worked there, I modified the Burger King jingle, thusly:
"Pound the bearings
file the clutches
bend some parts
(but not to much)
then wipe them down
and box them up
and send them away!"
Sadly, that was how the 2080s were put together in the beginning more often than I'd like to admit.
It's such a different "telescope world" these days. It used to be that "made in Japan" meant "cheap". Then, Japanese optics were all the rage and "made in China" meant cheap. Now, many of the best known APOs are made in China!
What's next?
But for the collector, or this one at least, looking to preserve one of these old Newts, I think it's well known that many of them were excellent optically, but some weren't, and we try to be prepared to deal with the ones that aren't.
Hopefully in a manner that preserves another one for future generations to enjoy!
-Tim.
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"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Greg:
I think your attributing malice where simple poor business sense would suffice.
I think all of these guys started out wanting to make a great product worthy of their names (or their made-up names, in the case of Meade Instruments).
-Tim.
Lew and Tim: the fact is OC charged a premium price (about $1200 in today's money) for a 4.25 inch telescope and about $5000 (in today's money) for a ten inch, prices that compare approximately to Obsession's (which will give you a bigger optic for that price but less iron in the mount).
He advertised 1/20th wave etc. He didn't want to turn out astrojunk because there were already competitors doing that. But he needed high volume like the astrojunk producers. So the business model became: provide a good mount and good tube and lie about the optics in a very specific way. This is not saying "600x magnification"! which is the lie that is used to attract know-nothings to an appropriately priced cheap department store scope. It is saying "1/20th wave!" That's meant to attract and deceive a very specific clientele. It's like those flies that have evolved to look like bees. They aren't the real thing but they look like it. These scopes were designed to mimic or exceed the look and feel of the companies that "delivered the goods" (Cave, Criterion), attracting the kind of clientele that was willing to drop those kinds of bucks, and then wham-o knowingly slip in the bad glass. And when we say bad glass we don't mean they didn't do 1/20th wave but delivered tenth, eighth, or quarter wave instead. We mean so bad that knowledgeable people with decades of experience in amateur optics cannot bring themselves to believe a company would consciously ship something like that.
It's somewhat ironic because my Mom and I traveled all over LA before looking at new and used OTAs before settling on the gleaming option in the Northridge show room. But it's no doubt that case that the more tattered used scopes I looked at would have been better than my 4.25".
Coming across this ten inch mirror and seeing some of the posts by Rod and a few others pretty much closes the deal for me. This company was *not* a 1960s version of Swayze, Torus, Royce, etc. In fact it wasn't even up to the level of Discovery. No, it wasn't even up to the level of the mass marketed China mirrors.
Well. Out of that period I did get a lifelong interest in astronomy and a great love of good telescopes. Thanks to OC I learned about the importance of a good mount. No doubt I get some credit for developing my own interest and pouncing on magazines and books way back then. My mother gets huge kudos for encouraging that interest. I don't think we can say that Optical Craftsmen "did its part."
I guess what rankles here, guys, is not so much the junk 10" mirror that came with a package and was priced reasonably even without the mirror. What rankles here is the enthusiastic ten year old and his Mom getting took for money that was not easy to come by.
I'm doing fine. I've got great scopes and staggeringly excellent mounts: a quality dimension OC taught me was important (right there in the showroom) and did deliver on their stated policy of providing "overbuilt" mounts. About five years ago I even dug up a good used f/10 4.25" mirror made by Optical Craftsmen to replace the junk one I had as a kid--I just about fell to the ground after I collimated it and dialed it in on Jupiter, the view was as good as a friend's Televue 101. I had thought that perhaps the "good" OC mirror was swiped during one of the two or three recoatings it got over the decades and a poorer mirror substituted. But no: this ten inch is pointing to a policy that was at work in both the entry-level 4.25 and the 10" and across the line.
Very bad karma for Dick Nelson.
OK, don't worry about me, I've got a five inch Tak & a C14 so I have a precision optic and an excellent mass manufactured optic and all is well in my astronomical world.  I have recently acquired a fiberglass OTA and a big mount from yesteryear made by a generic overpriced low quality 1960s company and I'm putting a nice OMI into it and it will be a nice and possibly even an excellent 10" f/6 Newtonian. There's fun ahead. Works for me.
greg n
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"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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deSitter
Post Laureate
Reged: 12/09/04
Posts: 3338
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My first two telescopes were perfect optically - a 3" Sears and a 6" Criterion that was swapped for the Sears. I guess I was spoiled. Like you I always lusted after an OC or a Cave - it's sort of sad to hear that some of these imagined paragons of excellence, weren't, and my humble telescopes were. My 3" was the equal of any telescope anywhere. The diffraction pattern looked like the output of Aberrator with zeros dialed in.
The OC is crying out for Royce and Protostar optics!
-drl
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
The OC is crying out for Royce and Protostar optics!
-drl
It's going to get an OMI. And that ain't bad. The spider vane assembly looks good. I'm trying to figure out what to do about the secondary. The obvious and cheapest thing to do is recoat it. If I'm totally down on OC I might replace it. The shape of the secondary is very specific however so it's not clear that this one is easily replaced.
I'm glad you had great child hood scopes!
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Well, I had a similar early experience with poor quality optics that by rights should have discouraged me from continuing in amateur astronomy. But they weren't from OC. They were a 50mm and a 60mm Tasco that were all my parents could afford for me for Christmas when I was 7 and then 12 years old. I used those scopes until I bought the OC in 1972, at age 19. I didn't even realize what a quality 60mm was capable of until the early 80's, when I bought an OTA from a friend to use as a guide scope on a 4.25" f/5 built at Cave by Ron Ezra in the evenings after work as a personal scope (a good one, too). That 60mm was the first one I ever saw detail on Jupiter with.
Now, what's the "biggest crime?": misrepresenting the quality of the optics in these old Newts (I don't believe any of them could really test a mirror to 1/20th wave), or victimizing millions of would-be amateur astronomers with department store optics that aren't worth a flying... ...that are pure junk? Heck, even the "well-respected" brand names of today are doing the latter.
Quote:
These scopes were designed to mimic or exceed the look and feel of the companies that "delivered the goods" (Cave, Criterion), attracting the kind of clientele that was willing to drop those kinds of bucks, and then wham-o knowingly slip in the bad glass. And when we say bad glass we don't mean they didn't do 1/20th wave but delivered tenth, eighth, or quarter wave instead. We mean so bad that knowledgeable people with decades of experience in amateur optics cannot bring themselves to believe a company would consciously ship something like that.
They all did/do that, Greg. Even Cave. Certainly Criterion (on average, several notches below OC), remember the Dynamax? And a Meade 826 I had on loan while I worked there and tested one night next to my OC on Saturn. That Meade soured me on their Newts, though many people here swear by them (and I have no doubt they made some good ones, and wouldn't be at all surprised if I had one of those so-so's that they would have let out the door without a second thought).
-Tim.
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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Mr Magoo
Pooh-Bah
Reged: 11/05/05
Posts: 1006
Loc: Franklin, Indiana
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You should show these images to the mirror making Gurus in the ATM forum. They can give you a good opinion on whether the mirror is able to be saved.
--------------------
Ken
Franklin, IN
Member, Indiana Astronomical Society
B.S.A. Astronomy Merit Badge Counselor
6" f/10 Dob
Vintage Sears Discoverer 4-6305A 60mm
Vintage Manon 60mm (The Marsha Scope)
Criterion RV-6
My CN Photo Gallery
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Robert Provin
professor emeritus
Reged: 08/14/06
Posts: 702
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Quote:
I will however grant the point about the hardware and the mount. The OC mount conditioned me to expect stability and good control over where I was pointing. When I first tried out the CG5 (the old one) and everything was jittering and the mount was bouncing I thought: what the *#%@! is going on here!
So, OC taught me the value of a good mount. There's a positive.
regards
Greg N
To add to my previous post, where OC really excelled was their mounts. The OC mount was way more stable than anything Cave put out and was at the time and for the price most likely the best that could be had. I still have one of Dick's "Connoisseur" mounts and will never part with it. The clock drive was another story, but there wasn't much available in the way of quality drives in those days.
While Dick definitely let some awful mirrors leave his shop, it was and still is my impression that most OC optics were good to acceptable with a few exceptional mirrors thrown in. I too have heard tales of bad Cave mirrors so Dick wasn't unique in this regard.
Tim,
I was an "itinerant" worker at OC as I only worked during summers and breaks in my academic schedule, being an undergraduate in college at the time. I was there off and on from about 1964 to 1968. To my best recollection, Brandt was there sometime during the later part of my tenure. It's been over 40 years and my memories are fading!
Greg,
If I were you, I would keep the scope and replace the mirror. In my view the OC 10 inch Connoisseur over-all was one of the best examples of its class and time. Truly a classic!
Robert
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rmollise
Postmaster
Reged: 07/06/07
Posts: 5323
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Quote:
He advertised 1/20th wave etc. He didn't want to turn out astrojunk because there were already competitors doing that. But he needed high volume like the astrojunk producers. So the business model became: provide a good mount and good tube and lie about the optics in a very specific way. This is not saying "600x magnification"! which is the lie that is used to attract know-nothings to an appropriately priced cheap department store scope. It is saying "1/20th wave!" That's meant to attract and deceive a very specific clientele.
IMHO, no difference in claiming "600x" and "1/20th" wave...same quest for the gullible. 
As I've said, many companies back then were not above selling bad primaries. Frankly, Criterion and Edmund (who used Upco as their optics suppier) were more consistent than TOC. Which is NOT to say there are not some superb Optical Craftsmen optics out there. It's just a shame they didn't live up to their name ALL the time.
Also, I gotta say, I never ran across a Tasco way back when with optics near as bad as some of the OCs. Tasco, of course, was often importing the cream of the Japanese crop...and many of their Department Store Scopes from the 60s KICK BOOTY!
--------------------
Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
Edited by rmollise (11/06/09 11:17 AM)
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Rod:
The two tascos I had as a kid both had the non-removable sliding eyepiece gizmoids, and they were terrible optically.
The no-brand 2.4" guidescope I still have is very good, OTOH, and the Mayflower 76mm f/16 is superb.
I will continue to look for an OC Connoisseur, and will deal with the optics when the time comes (if it ever does).
-Tim.
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"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Greg,
If I were you, I would keep the scope and replace the mirror. In my view the OC 10 inch Connoisseur over-all was one of the best examples of its class and time. Truly a classic!
Robert
Robert I appreciate your advice as well as all the other people on this thread which is one of the most interesting I've had the opportunity to participate in.
My plan is as follows. For my personal use, I will get an adapter made and use the OC tube with OMI optics and an AP900 QMD mount. I will use the original pier which is on wheels and this could in fact become my ready-to-roll-out "quick looks" configuration. Except for cool down of course. (If telescopes had a soul the OC would swoon to be on an AP, the AP next to the OC mount is like Michelle Pfeiffer next to Roseanne Barr). I will use it with a 2" Moonlite focuser.
There are some issues however. The new mirror is 60.85 inches focal length and the OC was 61.25. That's very close, and I think there's enough adjustment in the mirror cell bolts to move up half an inch. This came up in the context of the draw tube for the moonlite focuser. Ron at Moonlite suggested I go to a 1.75 draw tube but when I said I had some adjustment in the cell he said OK go ahead and try the 2".
I'm not really interested in the OEM focuser which "needs work" or replacement. Since I will use the scope with digital setting circles I will need to have a wide field, because the rotation of the tube changes the optical axis and thus loses the calibration of the digital setting circles (at least some). I have no idea how much this source of inaccuracy will be, but it seems to me the scope should be able to deliver a 2 degree field to give me maximum leeway.
This leaves the question of the clock drive. The good news is the motor is running but it isn't tracking. The clutch consists of a rear plate which can be tightened via four (I think four) screws. However, I think there is a second adjustment that involves some nylon tipped screws that tighten directly on the RA shaft. If these are not tightened down then the scope won't track even if the motor and worm are turning.
I'm hoping that the local team can get the mount's motor figured out. I'd like to get it fully functional but I don't think I'll be using it. When the time comes I can sell the whole thing as a complete OC Connoisseur set up with an AP adapter for buyers who would rather use an AP mount. That way all the bases are covered. I will even keep the OEM focuser for an eventual buyer who wants to fix it up, but as I say, someone who popped for a Parks focuser would have that covered and no one would be the wiser for it.
It's great to have Robert on the forum and maybe I can get some advice on various issues. Oh criminy. I forgot I'm not in the market for a big honkin' Losmandy dovetail to hold those rings. I have to look around, I might have a dovetail somewhere. Oh I do! The Celestron C14 dovetail that I replaced with Losmandy. Good enough.
This cheap complete system is adding up. It certainly would have been a much better deal if the mirror wasn't a joke. I sure as heck hope the OEM secondary spider works out OK because if I have to pop for a protostar this whole project gets pushed into next year.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Rod:
I will continue to look for an OC Connoisseur, and will deal with the optics when the time comes (if it ever does).
-Tim.
Tim if you're not on Astromart you're not seriously looking. For $12 one-time joining fee this is the best move you can make to get an OC. There were in fact two OCs for sale this past week, a 6" and an 8". Astromart has something like 50,000 members that are certifiably insane about astronomy.
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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tim53
Carpal Tunnel
Reged: 12/17/04
Posts: 2337
Loc: Highland Park, CA
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Greg
as I said. Before, I am on astromart.
I don't want another of the pacific instruments mounted ocs and I already have an excellent 6" f/10 newt.
I watch amart all the time, but I'm not aware of another oc recently. And if it's an 8" discoverer it's also going to be on the pacific instruments mount
Tim
--------------------
"In the old days, before the discovery of eruptions, the lava had to be carried by hand down the mountain and thrown on the sleeping villagers. This took a lot of time." - New Yorker Cartoon, ~ 1980
Hatch Observatory details:
http://www.cloudynights.com/ubbthreads/showflat.php?Cat=0&Number=3593949&page=0&view=collapsed&sb=5&o=all&fpart=1&vc=&PHPSESSID=
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Greg
as I said. Before, I am on astromart.
I don't want another of the pacific instruments mounted ocs and I already have an excellent 6" f/10 newt.
I watch amart all the time, but I'm not aware of another oc recently. And if it's an 8" discoverer it's also going to be on the pacific instruments mount
Tim
Sorry Tim must have missed/forgotten that one. Have you posted a "wanted" ad? That will bring things out of the woodwork. That's how I got my 10" f/6 mirror. Somehow when you placed a wanted ad I thought it wasn't on Astromart but somewhere else.
The six inch ad is #653804 and it has wheels, which I'm told were more often seen in the catalog than real life.
647978 was a September ad for an apparently superior OC f/8 mirror.
I just have to believe that most of OCs sales were in California and that if you keep an ad up sooner or later one will come your way.
regards
Greg N
--------------------
"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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Lew Chilton
Pooh-Bah
Reged: 10/20/05
Posts: 1139
Loc: SoCal
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Quote:
Lew: I didn't know anything about Coast Instruments, but I'd sure like to find a nice Treckerscope one of these days! I certainly didn't know Diebel had a connection with them.
-Tim.
Tim,
It was Coast Instrument (singular), not Coast Instruments - everybody makes that same mistake.
In 2006 I went to the federal archives near Perris, California to review the 1961 bankruptcy papers filed by Coast Instrument in July of that year. Included were a list of creditors without priority. That included John Dieble who was then a student living in South Pasadena, California. He lost ~$50 on some parts he had ordered from Coast Instrument. Tom Cave lost about $200, probably for mirrors made for Coast Instrument. (Yes, these companies often bought mirrors from each other when they got behind in their production.)
In the case of Coast Instument, a number of its mirrors were made by the well-respected 1930s Alvan Clark & Sons Corp. optician, Leland Barnes; possibly by Keim Precision Optics of Glendale, Calif. (who also did optical coatings); Ralph Furgerson (formerly of Stellarscope, later of TF Optical); and Cave Optical. And there were probably other sources of mirrors, as well.
As this useful thread amply shows, it is very eye-opening to see how each telescope manufacturer handled the stress of meeting production quotas. Despite the size of their ads and the impressiveness of their ad copy, these companies often operated in unbelievably small quarters with a only a few employees. Attempts to enlarge the operation often resulted in huge indebtedness and sometimes bankruptcy, as was the case with Coast Instrument, Inc.
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I don't get no respect, but my scopes do!
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1961 Swift 60mm model 839 (2); 2003 TV-102/GM-8; 1959 8" f/6 Treckerscope; 1959 8" f/7.4 Murray Scope; 1959 Fecker Celestar-4; 1978 4" Edmund Astroscan; c. 1986 4-inch Celestron-Vixen SP-C102; c. 1950 20X60 Saturn spotting scope; 1963 7X50 Nippon Kogaku binoculars; Unitron #114 alt-az mount (Swifty-tron)
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rmollise
Postmaster
Reged: 07/06/07
Posts: 5323
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Quote:
[In 2006 I went to the federal archives near Perris, California to review the 1961 bankruptcy papers filed by Coast Instrument in July of that year. Included were a list of creditors without priority. That included John Dieble who was then a student living in South Pasadena,
This may be The Man, but The Man spells his name Diebel, if I recall, so perhaps not.
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Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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rmollise
Postmaster
Reged: 07/06/07
Posts: 5323
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Quote:
Rod:
The two tascos I had as a kid both had the non-removable sliding eyepiece gizmoids, and they were terrible optically.
The no-brand 2.4" guidescope I still have is very good, OTOH, and the Mayflower 76mm f/16 is superb.
I will continue to look for an OC Connoisseur, and will deal with the optics when the time comes (if it ever does).
-Tim.
There is no doubt at all that Tasco sold some junk back then. It depended on who they imported. That said, the junk, like my pore li'l 3-inch Newtonian, was at the very bottom of their line.
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Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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mikey cee
Post Laureate
Reged: 01/18/07
Posts: 4107
Loc: bellevue ne.
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Quote:
There is no doubt at all that Tasco sold some junk back then.
Hey watch it there unk!  Mike
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7x35 and 10x50 sears tower binocs, 3" f/10 edmunds reflector, 2.4" f/11.7 manon refractor, 6" f/8 jaegers refractor, "The 8 Ball" 8" f/13.3 brandt refractor, 3" f/15.8 sans&streiffe refractor, 3.1" f/15 selsi refractor(towa 339), 2.4" f/15 sears refractor, selsi 30x30mm spyglass, criterion 5-draw 25x45x75x spyglass(1957), 4.25" f/14.8 tasco 20te.
Edited by mikey cee (11/06/09 06:55 PM)
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Lew Chilton
Pooh-Bah
Reged: 10/20/05
Posts: 1139
Loc: SoCal
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Quote:
Quote:
[In 2006 I went to the federal archives near Perris, California to review the 1961 bankruptcy papers filed by Coast Instrument in July of that year. Included were a list of creditors without priority. That included John Dieble who was then a student living in South Pasadena,
This may be The Man, but The Man spells his name Diebel, if I recall, so perhaps not.
Uncle Rod, yes, you're right. It was John Diebel, not Dieble. And, yes, he was that John Diebel.
P.S. Give me a break - a least I didn't spell his name John Decibel or John Diabolical! 
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I don't get no respect, but my scopes do!
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1961 Swift 60mm model 839 (2); 2003 TV-102/GM-8; 1959 8" f/6 Treckerscope; 1959 8" f/7.4 Murray Scope; 1959 Fecker Celestar-4; 1978 4" Edmund Astroscan; c. 1986 4-inch Celestron-Vixen SP-C102; c. 1950 20X60 Saturn spotting scope; 1963 7X50 Nippon Kogaku binoculars; Unitron #114 alt-az mount (Swifty-tron)
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rmollise
Postmaster
Reged: 07/06/07
Posts: 5323
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Quote:
Quote:
There is no doubt at all that Tasco sold some junk back then.
Hey watch it there unk! Mike
You didn't live through my Tasco Newt.
--------------------
Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
|
rmollise
Postmaster
Reged: 07/06/07
Posts: 5323
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Quote:
Uncle Rod, yes, you're right. It was John Diebel, not Dieble. And, yes, he was that John Diebel.
P.S. Give me a break - a least I didn't spell his name John Decibel or John Diabolical!
Believe me, I wasn't pickin' on your spellin'...what do they say about "He who lives in a glass house..."?
--------------------
Uncle Rod
Rod's New Book:
Choosing and Using a New CAT
Available now!
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gnowellsct
Pooh-Bah
Reged: 06/24/09
Posts: 1172
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Quote:
Quote:
There is no doubt at all that Tasco sold some junk back then.
Hey watch it there unk! Mike
Gotta be careful about callin' Rod out. I asked him to step outside on the Optical Craftsman reputation matter and got my butt whupped. And Tim didn't shoot him like he was supposed to. This Yankee is learnin' to be careful.
Greg N
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"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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