Return to the Cloudy Nights Telescope Reviews home pageAstronomics discounts for Cloudy Nights members
· Get a Cloudy Nights T-Shirt · Submit a Review / Article

Click here if you are having trouble logging into the forums

Privacy Policy | Please read our Terms of Service | Signup and Troubleshooting FAQ | Problems? PM a Red or a Green Gu… uh, User

Equipment Discussions >> Reflectors

Pages: 1 | 2 | 3 | (show all)
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
older 8" blue sonotube dob
      #6096811 - 09/23/13 01:12 PM

Who made 8" blue-painted sonotube dobs 12+ years ago with the focuser on the right side? Looks like your basic F/6 unit. I'm going to see one tonight, the seller doesn't know who made it. It doesn't look like a homemade job.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Natty Bumppo
member


Reged: 08/30/13

Re: older 8" blue sonotube dob new [Re: precaud]
      #6096844 - 09/23/13 01:30 PM

Does it have a thick heavy single vane spider? If so my first guess would be a Coulter. Although Discovery PDHQ dobs are also blue with focuser on the right. Might be an 8" f/7 PDHQ.

Edited by Natty Bumppo (09/23/13 01:34 PM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: Natty Bumppo]
      #6096857 - 09/23/13 01:37 PM

Hmmm... I don't have a pic of the front, but I see spider mounting screws at quarter points. It's not long enough to be an F/7 - that would be a nice find if it was an F/7 Discovery, though!

Post Extras: Print Post   Remind Me!   Notify Moderator  
Jon Isaacs
Postmaster
*****

Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: older 8" blue sonotube dob new [Re: Natty Bumppo]
      #6096862 - 09/23/13 01:40 PM

Quote:

Does it have a thick heavy single vane spider? If so my first guess would be a Coulter. Although Discovery PDHQ dobs are also blue with focuser on the right. Might be an 8" f/7 PDHQ.




If it i 12 years old, it is unlikely that it's F/7, at that time they were pretty only making F/6's.

Any link or photos? Craigslist?

Jon


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: Jon Isaacs]
      #6096875 - 09/23/13 01:49 PM Attachment (61 downloads)

I don't know the age, only that is at least 12 years old. This is the only pic I have.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Jon Isaacs
Postmaster
*****

Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: older 8" blue sonotube dob new [Re: precaud]
      #6097039 - 09/23/13 03:58 PM

I saw that ad but I thought it was a 10 inch???

From the proportions it looks like a 6 inch to me. If it's an 8 inch, it's a long focal length.

Jon


Post Extras: Print Post   Remind Me!   Notify Moderator  
csrlice12
Postmaster
*****

Reged: 05/22/12

Loc: Denver, CO
Re: older 8" blue sonotube dob new [Re: Jon Isaacs]
      #6097044 - 09/23/13 04:01 PM

As long as the optics are good, that thing will kill on planets........

Post Extras: Print Post   Remind Me!   Notify Moderator  
Natty Bumppo
member


Reged: 08/30/13

Re: older 8" blue sonotube dob new [Re: csrlice12]
      #6097068 - 09/23/13 04:11 PM

It looks like its setting on an Orion base, any chance it could be an old pre-Synta Orion? I don't recall what their older ones were like. Then again, the altitude bearings appear to be from a Meade Lightbridge. Could be a homebuilt "Frankenscope". I agree with Jon, 6 or 8", it's a long f/l.

Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: csrlice12]
      #6097072 - 09/23/13 04:13 PM

Yeah, it's definitely not a 10", but I thought I'd break that news to him in person. He says it's 50"-ish high so that's why I thought 8" F6.

So it's not reminding anyone of anything from that period?

Agreed, the proportions look more like a 6". The base looks awfully squat even for a 6.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Zamboni
scholastic sledgehammer
*****

Reged: 01/03/05

Loc: Colorado Springs
Re: older 8" blue sonotube dob new [Re: precaud]
      #6097148 - 09/23/13 04:59 PM

Definitely not a pre-synta orion. The earliest ones were white, later models were black.

I think that's a homemade job on an old Orion base. Just a guess.


Post Extras: Print Post   Remind Me!   Notify Moderator  
youngamateur42
Pooh-Bah
*****

Reged: 11/21/12

Loc: La Verne, CA
Re: older 8" blue sonotube dob new [Re: Zamboni]
      #6097264 - 09/23/13 06:34 PM

Looks like a home brewed scope (and tube) put on an Orion or similar mount. I've people do this before

Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: older 8" blue sonotube dob new [Re: youngamateur42]
      #6097373 - 09/23/13 08:21 PM

That' looks like a ten inch wide tube - particularly if that's a 50mm finder. The finder is the wildcard here - if you get the mm on that then you can measure out the rest. It could potentially be a 10" scope . I'm looking for something to scale by and its elusive.

I agree its looks like a home brew - could be a great scope though with a custom mirror - you dont know . and just an FYI - there's a far better way to counter balance a reflector than the pic shows.

Pete



Edited by azure1961p (09/23/13 10:04 PM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: azure1961p]
      #6097739 - 09/24/13 12:29 AM

Well we were right, it is not a 10" but an 8" F/6 homebuilt. Could very well have been made from a kit. The guy lives in a green zone (close to blue) and the views were fantastic even before it turned fully dark. The primary had no center spot, and in 10 years of owning it, he had never collimated it. I was inclined to say no thanks but decided to collimate it (it was WAY out) and take a peek. The primary was filthy but clearly very good - stars were sharp, 250lpi Ronchi looked clean and straight, and star test was perhaps the best I've seen, looking the same on both sides of focus. Could very well be a premium mirror. I looked on the back of it for any identifying marks but saw none except the focal length written. The mount and altitude bearings need a little TLC but nothing difficult. For seventy bucks it will be fun to clean up and play with.

Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: Jon Isaacs]
      #6098153 - 09/24/13 10:19 AM

Quote:

I saw that ad but I thought it was a 10 inch???




So, Jon, inquiring minds want to know: You're in CA; do you watch CL ads for telescopes as far away as NM ?


Post Extras: Print Post   Remind Me!   Notify Moderator  
Jon Isaacs
Postmaster
*****

Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: older 8" blue sonotube dob new [Re: precaud]
      #6098471 - 09/24/13 01:18 PM

Quote:

Quote:

I saw that ad but I thought it was a 10 inch???




So, Jon, inquiring minds want to know: You're in CA; do you watch CL ads for telescopes as far away as NM ?




No..., I pretty much stick with San Diego and every so often ajoining counties. There are times when I look at Phoenix.

In this case, I saw you were in New Mexico so I did a search on Dobs...

It's looks like you good a nice scope. Any more details? Focuser, type of mirror cell, secondary? Over the years, I have gotten some good deals on 8 inch F/6 Dobs but I never end up keeping them because there never seems to be a reason to choose an 8 inch F/6 over my 10 inch F/5...

Jon


Post Extras: Print Post   Remind Me!   Notify Moderator  
Calypte
Pooh-Bah


Reged: 03/20/07

Loc: Anza, California
Re: older 8" blue sonotube dob new [Re: Natty Bumppo]
      #6098520 - 09/24/13 01:41 PM

Quote:

It looks like its setting on an Orion base, any chance it could be an old pre-Synta Orion?



Those were made by Pirate Telescopes, which morphed into Discovery. A friend of mine made them, DBA Pirate. The scope in the picture doesn't look to me like a Pirate or Orion scope.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Jon Isaacs
Postmaster
*****

Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: older 8" blue sonotube dob new [Re: Calypte]
      #6098607 - 09/24/13 02:18 PM Attachment (20 downloads)

Quote:

Quote:

It looks like its setting on an Orion base, any chance it could be an old pre-Synta Orion?



Those were made by Pirate Telescopes, which morphed into Discovery. A friend of mine made them, DBA Pirate. The scope in the picture doesn't look to me like a Pirate or Orion scope.




My very first Dob was a used Pirate Instruments 8 inch F/6. It was pretty crude, single wire secondary mount and the mirror cell was made from lead for balance...

Here's a photo of it along with my 12.5 inch F/4.06 in it's original incarnation..

JOn


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: Calypte]
      #6098617 - 09/24/13 02:23 PM

Quote:

In this case, I saw you were in New Mexico so I did a search on Dobs...




Ah, you were just being resourceful, then

It has a 1.25" helical focuser, 6x30 finder sitting way too close to the OTA for comfortable use, 4-vein spider, the primary is glued to a laminated particle board cell. The primary is absolutely filthy, the scope was stored pointing straight up with no front cover. I'm painting the exposed particle board on the cell prior to cleaning the mirror to water-proof it. It was definitely made from a kit - all of the hardware is very consistent - blackened, hex heads, etc. Will post pics later.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Calypte
Pooh-Bah


Reged: 03/20/07

Loc: Anza, California
Re: older 8" blue sonotube dob new [Re: Jon Isaacs]
      #6099505 - 09/24/13 11:09 PM

Quote:

My very first Dob was a used Pirate Instruments 8 inch F/6. It was pretty crude, single wire secondary mount and the mirror cell was made from lead for balance...



I asked my friend, and he agrees (i.e. "crude"). But he points out that the scope sold for only $299.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Jon Isaacs
Postmaster
*****

Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: older 8" blue sonotube dob new [Re: Calypte]
      #6099857 - 09/25/13 07:35 AM

Quote:

Quote:

My very first Dob was a used Pirate Instruments 8 inch F/6. It was pretty crude, single wire secondary mount and the mirror cell was made from lead for balance...



I asked my friend, and he agrees (i.e. "crude"). But he points out that the scope sold for only $299.




Curtis:

Is your friend still making mirrors/telescopes ? I have a sneaky suspicion the answer is yes..

Jon

Edited by Jon Isaacs (09/25/13 07:36 AM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
Calypte
Pooh-Bah


Reged: 03/20/07

Loc: Anza, California
Re: older 8" blue sonotube dob new [Re: Jon Isaacs]
      #6100189 - 09/25/13 11:43 AM

Quote:

Is your friend still making mirrors/telescopes ? I have a sneaky suspicion the answer is yes..

Jon



Yes. Mirrors, both primaries and secondaries. Mostly contract work. No scopes.


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: Calypte]
      #6101179 - 09/25/13 07:54 PM Attachment (23 downloads)

I forgot to take pics before I started, but the mirror cleaned up perfectly. There must be something protective about NM dust, because this is now the second mirror that I've bought that had years of local dust accumulation on it that was in fabulous shape underneath!

The blue-green hue of plate glass is clearly visible, as well as the particle board cell.

I taped between the cell and mirror to prevent water from getting in between them. Is there any reason not to leave the tape in place?

Next job is to center spot it (with the photo centering technique, of course!).

Oh, and in the background is my 16" mirror which just arrived with a new figure and new coat...


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: precaud]
      #6101186 - 09/25/13 07:57 PM Attachment (24 downloads)

In the off chance that someone might recognize the components and identify where this kit came from, I'll post a couple more pics. Here's a view of the OTA front.

Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: precaud]
      #6101191 - 09/25/13 08:01 PM Attachment (24 downloads)

And one of the 4" molded plastic altitude bearings. The previous owner thought it moved too easily and had wrapped duct tape around it for resistance. The tape adhesive had hardened long ago and was a pain to remove. Also visible is where the original kit builder had misplaced the bearings and covered up the gap with blue marker pen... sigh.

Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: older 8" blue sonotube dob new [Re: precaud]
      #6101466 - 09/25/13 10:58 PM

It could still be a gem despite the rough around the edges mechanics . You might want to spray the tube with Kilz to coverup ink before you paint to prevent pigment seepage. I'm curious to see how this one performs.

Pete


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: azure1961p]
      #6101603 - 09/26/13 12:51 AM

Good idea on the sealing primer, Pete, thanks. This one is definitely rough around every edge, but the mirror is superb. I was just out with it, collimated it on a star (what a pain... first order of business is to put a center spot on this thing so I can use tools!). I compared it to my AD10 on several targets, and this mirror is excellent. Sharper, and better contrast, background is just plain darker with less "haze" around stars. When viewing M31 tonight, I could clearly see M110 in this scope, whereas it was barely discernible in the AD10 (without CC). A diamond in the rough.

I really don't like seated viewing from the left side. My body was protesting the whole time. It doesn't like being contorted that way. I'm going to move the bearings over for right-side viewing. That would be a good time to repaint the tube.


Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: older 8" blue sonotube dob new [Re: precaud]
      #6101810 - 09/26/13 08:06 AM

Interesting as Im a dyed in the wool left side observer - always have been. Something to consider - and its simple and cheap with big pluses - mount a 100mm DC powered fan suspends by rubber bands behind the primary. It speeds cooling but more than that, helps get rid of the heat within the tube and it shows in the tighter star images - even at low power .

Pete


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: azure1961p]
      #6102014 - 09/26/13 10:19 AM

I suppose it could just be poor focuser and finder placement that is the cause of the discomfort.

Interesting you mention cooling, I was wondering about that very thing last night as I watched tube currents morph the star test image. There's no way to get air to the back of the mirror when it's glued to the particle board cell. Is it still worthwhile having a fan back there?


Post Extras: Print Post   Remind Me!   Notify Moderator  
Jon Isaacs
Postmaster
*****

Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: older 8" blue sonotube dob new [Re: precaud]
      #6102096 - 09/26/13 10:56 AM

Quote:

I suppose it could just be poor focuser and finder placement that is the cause of the discomfort.

Interesting you mention cooling, I was wondering about that very thing last night as I watched tube currents morph the star test image. There's no way to get air to the back of the mirror when it's glued to the particle board cell. Is it still worthwhile having a fan back there?




It's worthwhile have a fan back there.. some holes in the cell, a new cell..

Left versus right.. I have scopes both ways.. it really doesn't matter but focuser and finder location are critical for comfort. Looking at the photos, it looks to me like the focuser is at maybe 60 degrees, nearly vertical. I think something closer to 40 degres is much more comfortable.

Jon


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: Jon Isaacs]
      #6102149 - 09/26/13 11:23 AM

Quote:

It's worthwhile have a fan back there.. some holes in the cell, a new cell..




Thanks Jon. I definitely see the disadvantage of not being able to wash air over the back of the mirror to cool it. A new cell eventually, perhaps, but not anytime soon.

Quote:

Looking at the photos, it looks to me like the focuser is at maybe 60 degrees, nearly vertical. I think something closer to 40 degres is much more comfortable.




Viewing the OTA from the front as a clockwise circle with 0* being straight up, the focuser is at about 330* and the finder is about 355*, not even at the top, and sitting too close to the tube. So you're right, the focuser is sitting too far atop the tube, no question.


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: precaud]
      #6102525 - 09/26/13 03:08 PM Attachment (18 downloads)

Took the 2ndary out for cleaning. Does anyone know who makes this? It looks like a unique design.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Jon Isaacs
Postmaster
*****

Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: older 8" blue sonotube dob new [Re: precaud]
      #6103526 - 09/27/13 05:41 AM

Quote:

Took the 2ndary out for cleaning. Does anyone know who makes this? It looks like a unique design.




I can't put my finger on who made it but it looks pretty standard, it could even be an AstroSystems, I have two of them and they are both different.

Jon


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: Jon Isaacs]
      #6103941 - 09/27/13 11:08 AM

Thanks Jon, you're right. Looking at the photos on their website, it was never clear to me if that angled piece was a shroud that fit over the 2ndary or an angled sleeve that it attached to.

I center-spotted the primary mirror and collimated it yesterday. I definitely need to replace those Philips head 2ndary adjustment screws! Ugh!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Calypte
Pooh-Bah


Reged: 03/20/07

Loc: Anza, California
Re: older 8" blue sonotube dob new [Re: precaud]
      #6104227 - 09/27/13 01:21 PM

It looks identical to the secondary holder in my 1973 8-inch Cave Newt.

Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: azure1961p]
      #6107066 - 09/29/13 08:44 AM

Quote:

Interesting as Im a dyed in the wool left side observer - always have been.




Pete, are you either left-handed or a left-eye observer? It became clear to me last night the two ergonomic reasons why I prefer right-side observing.

: Left hand guides the OTA, right hand works the focuser.
: The right arm comes in roughly parallel to the OTA and just feels more comfortable.

The one thing I'll say for left-side observing is that it predisposes me to use both eyes - left eye for the finder, right eye for the eyepiece.


Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: older 8" blue sonotube dob new [Re: precaud]
      #6108102 - 09/29/13 07:56 PM

I'm a left eye observer. I'm right handed so I guide with that arm . I focus with my right too. Left hands for holding another eyepiece or filter.

Pete

Edited by azure1961p (09/29/13 07:57 PM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: azure1961p]
      #6196240 - 11/15/13 10:14 AM Attachment (6 downloads)

This is the old cell. It provides a good wavetrap (absolutely no reflections around the mirror), but it also provides absolutely no cooling!

Post Extras: Print Post   Remind Me!   Notify Moderator  
herrointment
Post Laureate
*****

Reged: 03/12/11

Loc: North of Hwy. 64
Re: older 8" blue sonotube dob new [Re: precaud]
      #6196832 - 11/15/13 04:47 PM Attachment (4 downloads)

Late 1970's Novak?

Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: herrointment]
      #6197257 - 11/15/13 09:46 PM

Interesting... it looks identical.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Space_Girl1234
member


Reged: 03/06/11

Re: older 8" blue sonotube dob new [Re: precaud]
      #6197428 - 11/15/13 11:00 PM

Is a Pirate telescope a good one?

My grandpa has a big one that is taller than me.


Post Extras: Print Post   Remind Me!   Notify Moderator  
precaud
scholastic sledgehammer
*****

Reged: 12/05/12

Loc: north central New Mexico
Re: older 8" blue sonotube dob new [Re: Space_Girl1234]
      #6197472 - 11/15/13 11:51 PM Attachment (3 downloads)

Ahhh, now that's more like it!

A huge thank you to the CN forum member who, in response to my wanted ad, sent this UO cell to me and refuses to accept payment for it. What an amazing group we have here.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | 3 | (show all)


Extra information
10 registered and 33 anonymous users are browsing this forum.

Moderator:  ausastronomer, Phillip Creed, JayinUT, okieav8r 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 1264

Jump to

CN Forums Home


Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics