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The Year-Long 60mm Telescope Challenge

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#76 jrbarnett

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Posted 12 April 2013 - 08:48 PM

Good thoughts. I too am figuring out what my strategy is going to be. Like Carol, I'll kick off my formal effort tomorrow (Saturday) at the OFLI monthly star party. I'm leaning toward picking a handful of constellations that will be well placed during the session, and concentrating on those, mixing doubles and DSOs.

I can already hear the grief from the OFLI crew, though, when I field two 60mm scopes Saturday. But I'm used to it by now.

- Jim

#77 desertstars

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Posted 12 April 2013 - 10:24 PM

Fortunately, the crowd I observe with is aware of the Old Scope's history. They treat it with the respect a "vintage" telescope deserves.

Hmmm... does a 1970 60mm refractor really qualify as "vintage?" Because if it does, well, I bought the thing for myself. Which would make me... Uh... Mature. :crazy:

#78 buddyjesus

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Posted 12 April 2013 - 11:17 PM

No love for Uranus, Neptune or Titan?

One of my favorite small scope targets was overlooked, probably because it is naked eye and is tough to fit in the field of view of a telescope. The Alpha Persei association. Didn't see M76 either unless I am mistaken. muhahahahaha! :mrevil:

BTW, in my home site, I wouldn't be able to complete this list because of the light pollution and Michigan skies with my 4" scope. There is no miracles, except power outages, but they don't occur when there is no clouds out around here.

I really dig your showing of love for doubles!

#79 droid

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Posted 13 April 2013 - 05:02 AM

Fortunately, the crowd I observe with is aware of the Old Scope's history. They treat it with the respect a "vintage" telescope deserves.

Hmmm... does a 1970 60mm refractor really qualify as "vintage?" Because if it does, well, I bought the thing for myself. Which would make me... Uh... Mature. :crazy:



A star geezer?

We are battling clouds, clouds and rain , non stop.

#80 Chuck Hards

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Posted 13 April 2013 - 08:57 AM

No love for Uranus, Neptune or Titan?


Right on!

I mentioned planetary satellites and asteroids earlier in this thread, and will certainly try for as many as possible. Patience is the key with minor planets, since you need to notice motion over time in order to positively ID them visually. How crowded the star field is can also add to the difficulty.

#81 jrbarnett

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Posted 13 April 2013 - 09:46 AM

Okay. Just for you two guys. Here's a bonus 60mm target. Ceres. :grin: Now you have 890 targets to chase. Okay, okay. Let's make it 891. Vesta, too.

This list has some very hard inclusions. To conflate and transliterate W.T. Olcott and Dorothy from the Wizard of Oz, "We ain't in Starland anymore, and we don't even have a 3-inch telescope!" There's plenty within reach of a 60mm that isn't listed. But also there's plenty on the list that may not be reachable by any 60mm, anywhere on Earth, by anyone. I just don't know. That's what makes it a challenge. Think of it like this. You're out taking a peek at Luna and Saturn, and..."I'll piggy back the 60mm and knock off a few we'll placed targets on that list while I'm out. Hmm...that wasn't too bad. I'll try these three tougher ones. Man, am I shocked or what? Who knew you could see *that* in a 60mm from the 'burbs?" To me that would be success for this project.

I like the challenge concept. Dave Mitsky and his "challenge objects" postings have always been inspirational and aspirational for me. This is the first "Challenge" type article for me, and I don't expect it to be perfect, though I do hope that it is a perfectly adequate start to a larger process.

Who knows. Perhaps a whole separate Solar, Lunar and Planetary "solar system" small scope challenge, or the C8 "bests" challenge mentioned earlier, or a Virgo-CVn-Com single night galaxy marathon called "Markarian's Revenge", or a "Loveliest double star in a XXmm telescope, and why" participatory essay contest (with bonus points for more flowery written description of said star), etc. Other possibilities include aperture specific cross-over efforts with other CN articles. For example, Steve Coe's "What's up" column is a rich source of seasonally grouped targets. Perhaps tackle the targets in one month's column with 4-inchers? The possibilities are virtually endless.

60mm, though, because it was a starting point for so many of us of a certain age seems to me to be a pretty good place to start on the "challenge article" concept. If there's a subtext here, it is this. In my opinion, the single most over-estimated characteristic of a telescope is...aperture. Aperture not only isn't king, it's scarcely even "royal". A fat stack of contrast transfer graphs isn't worth the paper it's printed on next to the real king. Far and away skill, experience and persistence rule all in our hobby.

Regards,

Jim

#82 Vesper818

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Posted 13 April 2013 - 02:46 PM

Thomas
In the 60mm Club files, that list that Larry put into xls files was your compilation, correct?
I could not access your doc file, so formatted and printed his list .

#83 Chuck Hards

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Posted 13 April 2013 - 07:47 PM

Okay. Just for you two guys. Here's a bonus 60mm target. Ceres. :grin: Now you have 890 targets to chase. Okay, okay. Let's make it 891. Vesta, too.


Oh, I'll go a bit deeper than those two, but thanks for tossing us a semi-official bone. :grin:
I've seen those in the 8x20mm binos stashed in the glove compartment of my Mazda.

I really want to push the 50mm f/20 as far as I can. I could break out my vintage Penncrest 60mm f/16.6, but it's .965" focuser and eyepieces really don't instill much confidence. Maybe a hybrid diagonal is the answer, so I could use 1.25" eyepieces. I don't want to retrofit a 1.25" focuser because the scope is just about mint, and I want to keep it bone-stock.
I've got several 60mm objectives of assorted pedigree, and could just put an OTA with 1.25" focuser together I suppose, but the 50mm is calling to me. I'll give the little guy a shot first.

One modern crutch I'll be using is a dielectric diagonal. Need to conserve every photon since there aren't any to spare.

#84 jrbarnett

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Posted 14 April 2013 - 02:58 PM

Though some who have purchased optical groups from the same source have claimed otherwise, the Carton doublets I have are uncoated. I've had all three of them apart for deep cleaning and they are as shiny and reflective as window glass. Nonetheless, I did get a chance to use the modern 60mm triplet and one of the Carton's last night under terrible seeing, high thin clouds and with a sliver Moon in the west. I'll put up my observing report in a few when I get my notes out of the car during unloading, but what I found is that at least under suburban skies it's all about managing exit pupil and increasing contrast with these little guys. The long focal length of the Carton made small exit pupils mandatory. It did help contrast on galaxies in particular.

I won't say my session was everything I dreamed it would be, given the non-optimal conditions, but I am off to the races on the list. Thinking back, I'd say that I probably observed around a dozen list targets and a couple of others not on the list. The AT60EDT with a 50mm 2" Plossl was riotous in finder role. The Pleiades were a small-ish cluster in the center of a much larger star field in the scope. It's tough to perfectly mutually align each half of the dual mount, but I shimmed the dovetail on the Carton and got the two scopes close enough to aligned that anything in the center of the Carton's FOV at 90x was only slightly off center in the AT60EDT's low power field. Very workable.

Regards,

Jim

#85 Charlie Hein

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Posted 14 April 2013 - 06:31 PM

Gardner unfortunately CN doesn't let me upload the ST3 ".stx" format files. :( There is a notice that pops up warning that .stx is not one of the permitted attachment formats.

PM me your e-mail address and I'll e-mail you the list in .stx format.

Regards,

Jim


Jim, try "zipping" the file.

Charlie

#86 jrbarnett

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Posted 14 April 2013 - 07:02 PM

Thanks Charlie. I'll give it a shot.

Regards,

Jim

#87 yashi

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Posted 18 April 2013 - 04:24 AM

does anyone have this list as a excel/google docs/ calc table?


the formating is making the convertion complicated :/

how did you compile this list in the first place? based on which data?

edit: nvm. i managed to do it


#88 jrbarnett

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Posted 18 April 2013 - 11:23 AM

Yashi, the list was generated using Sky Tools 3, an observation planning application for Windows PCs.

Regards,

Jim

#89 yashi

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Posted 19 April 2013 - 05:01 AM

thank you.

How exactly does this program creates these lists? Do you filter the known objects by different properties, like (brighter than x, separation bigger than x -> for multiplestar-objects?)

#90 jrbarnett

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Posted 19 April 2013 - 02:19 PM

Exactly.

The application contains an enormous database of stellar and non-stellar objects. It also has models and algorithms for user variables, telescope and eyepiece variables, location and site condition variables, etc. This particular list assumes a 38N location (Santa Rosa, CA), an early April 2013 date, a clean 60mm telescope, a middle aged experienced observer, and ignores daylight and the difficulty of the target in the stated aperture. Only doubles stars with Bayer designations, commmon names or Flamsteed numbers were selected. DSOs were less restricted by catalog.

The difficulty designations are based on a rating formula used by the application for the values I set for the variables. There are several applications that work similarly to Sky Tools, including one for the Mac OS and another excellent one for Windows.

Regards,

Jim

#91 PitchHitter

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Posted 20 April 2013 - 12:44 AM

Actually Jim, I would claim the title of The most interesting Astronomer. After all I coined the term Clear Skies at the 1974 WAA convention as a sign-off on formal letters and general greetings to bring attention to the problems of light pollution. Prior I started the first sanctioned Astronomy and Rocketry Club in California and after looking through my Homemade 6" telescope around 1970 George Lucas became so enthralled at Saturn and Jupiter from the streets of Del Mar that he dusted off his manuscripts and finished "Star Wars" resulting in over a $100 billion industry. Then in 1976 I was the WAA Convention Chairman at 21, again with the purpose of bringing attention to the plight of the 200" Hale Telescope on Mt. Palomar and I moderated the 2 hr. worldwide broadcast on Space Exploration with NASA, JPL, L-5 and the Planetary Society. Then I began work with family friend Bill Bradley to write San Diego County's Dark Sky Ordinance and my terms were used in the Federal Ordinance and finally again in California in 2001. I could go own but natural Crockett modesty prevails.

Now Jim, wouldn't you say every time I used my 60mm finderscope, I was meeting your challenge? Then I follow it up by a 9mm exit pupil, 28x general scan. No ! 8mm is not a limit for everybody.

No matter what is in the field, the longest line is to the scope I bring. :cool:

#92 jrbarnett

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Posted 20 April 2013 - 01:20 PM

Problem is, when you speak you don't use words that would break the jaw if spoken by a lesser man. But I will give you an "A" for effort, and dub thee "Most Interesting Astronomer in Southern California". And everyone knows that it's what we grow here in NorCal that gave Lucas his creative genius not a peek at Saturn! And before anyone gets up in my grill about TOS and this being a family channel and such, we grow the finest WINE GRAPES in the world. Among other things. Like apples. :lol:

Regards,

Jim

#93 yashi

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Posted 22 April 2013 - 02:28 AM

thank you very much. This list looks like a great start into "structured" astronomy then. Although im living at 52° it should work for the most part.

#94 demiles

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Posted 22 April 2013 - 08:18 PM

I take my AT66 out to SQM 21 skies at least a few times year and it's amazing how deep you can go with such small scope. I'll work on the list next time I go out.

#95 GlennLeDrew

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Posted 30 May 2013 - 01:39 PM

To qualify as a "challenge" listing, a great many spectacular (even naked eye) objects should be removed, and other accessible fare added. I should hope that more than those suffering significant light pollution can contribute. And if only the light polluted need apply, to what level of sky brightness?

I know that two-eyed viewing affords a gain in signal to noise of 41%, effectively increasing the aperture by 19%. But my 60mm bino is limited to 20.8X, which does impact depth of penetration for stars and smaller objects. Just a few of the many objects seen with my bino and which are not on the list:

Cocoon neb
California neb
Heart and Soul nebulae (although the related clusters are on the list)
Gamma Cyg neb
North America and Pelican neb
Veil neb, incl. Pickering's wisp.
NGC 4565 edge-on galaxy

And how about dark nebulae? With my binos I see scores of them.

For larger objects, a large field of view is most advantageous. In the mono scope arena, a 60mm f/7 taking 1.25" eyepieces will deliver a 3.6 degree FOV. And a narrow band filter will bring out those really low surface brightness nebulae.

One interesting observation made years ago with just such a Carton 70mm f/7. I stacked a couple of Barlows to obtain a quite tiny exit pupil. I actually resolved a handful of M13's brightest giants!

#96 Chuck Hards

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Posted 31 May 2013 - 07:34 AM

Boy, Glenn, NGC 7000 might be a toughie for my 50mm f/20, at least all in one bite. I'm not sure I could fit the entire complex into the FOV, no matter what eyepiece I used.

But you've piqued my curiosity and I'm going to give it a go.

The best views I've ever had of the North America nebula were with the naked-eye, followed closely by a 3X "spy" binocular (field glass, really).

#97 Astrojensen

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Posted 31 May 2013 - 02:35 PM

Boy, Glenn, NGC 7000 might be a toughie for my 50mm f/20, at least all in one bite. I'm not sure I could fit the entire complex into the FOV, no matter what eyepiece I used.



I've seen it with my 63mm Zeiss and several different eyepieces. Most of the continent shape fits in an eyepiece giving a 2° TFOV. If your scope can use 2" eyepieces (unlikely, I'll admit, but if not, you should consider making a different OTA, with a 2" focuser!), a 40mm/70° eyepiece should do the trick.

2" eyepieces on small long-focus achromats can make for breathtaking views. Users of Zeiss Telementor 2's and Zeiss Telemators and AS63/840s with original OTAs should be aware that adapters to fit 2" diagonals and eyepieces to these scopes are readily available from Baader Planetarium. Adapters also exists to fit 2" equipment to Vixen M43 threads.


Clear skies!
Thomas, Denmark

#98 GlennLeDrew

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Posted 01 June 2013 - 02:07 PM

I've long advocated the notion of slapping a 2" focuser on those long, skinny 60mm 'soda straws'. :grin: as Thomas notes, the views are spectacular! Even the really cheap eyepieces deliver at those long f/ratios.

Imagine a 46mm field stop behind a 1,000mm objective; the TFoV would be 2.6 degrees. And if the eyepiece were a TV 55 or Meade 56, that would be 18X at a 3.3mm exit pupil. Such notorious objects as M33 would be a doddle. You could easily use a narrow band nebula filter, and all those big, low surface brightness nebulae would suddenly be accessible.

Restricting to 0.965" (and even 1.25" eyepieces) is a veritable crime, when a most highly corrected, wide field can be obtained.

My bino (interchangeable 50mm and 60mm objectives) has 2" focusers. With the 60mm f/4.5 objectives and 30mm 70 degree AFoV eyepieces (working together as a 9X60), I enjoy a 7.7 degree TFoV. H-beta filters nicely bring out such fare as the California nebula.

#99 Astrojensen

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Posted 01 June 2013 - 03:56 PM

I never understood the reason to limit even very small scopes to 0.965" eyepieces, which is one reason I'm not a huge fan of older Japanese scopes. It limits TFOV somewhat terribly. At least Zeiss understood this from the very beginning and put M44 (1.7") focusers on all their 60mm scopes ever made, from 1898 to 1995, giving you the option to use eyepieces much bigger than 0.965", if you wanted.

My first 2" eyepiece was a 40mm GSO Kellner. It was *insanely* sharp on the 63mm f/13.3 Zeiss. That eyepiece mysteriously got lost at a star party and was replaced at the next star party by a 42mm Sky-Watcher Reverse Kellner, which I won in a raffle. Justice! That 42mm eyepiece is even sharper, notably around the edge, but eye comfort isn't as good. Still, it is fantastically sharp and throws up some amazing views. It is now more or less replaced with a 30mm ES82, which is a *fabulous* eyepiece on the 63mm Zeiss. Eventually, I think I'll get a 40mm ES68, for those lowest power views. Just for the heck of it!

People who have never experienced a 60mm long-focus achromat with a 30mm or 40mm 2" wide field eyepiece under dark skies just simply have no idea of what these scopes are capable of and underrate them terribly.


Clear skies!
Thomas, Denmark

#100 Chuck Hards

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Posted 01 June 2013 - 06:32 PM

The 50mm f/20 is home-built. It uses a 1.25" focuser that I turned on the lathe to fit the 2" OD main tube. I too have no use for the .965" format.

Posted Image

That's an erecting diagonal in the photo because the last time I used it was for some birding. At night, I use a dielectric mirror diagonal.

Attaching a 2" focuser, while possible, probably won't happen on that little guy, and would look very odd- the eyepiece barrel would be the same size as the main tube, lol!

I do have 80mm & 100mm ED scopes with 2" focusers, as well as a 110mm doublet with a 2", though of course they don't have long focal ratios without using a Barlow. I would never retrofit a 2" focuser to my 60mm f/16 Penncrest because it would lose value if no longer stock. It's pristine.

I have a drawer full of long-focus 60mm doublets so perhaps I'll build an OTA with one of those and incorporate a 2" focuser.






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