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Frustrated with 3.5

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#1 paulandrei

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Posted 12 July 2014 - 05:46 PM

Hi
I inherited a well used 69' 3.5 basic model some years ago. I have not been impressed with the proformance. I talked to someone at Company 7 about a cleaning. He mentioned that because of the age I might consider having it cleaned, and shelving it as an heirloom. He suggested I then buying a newer model with better tracking, optics, mirror, coatings, and eyepieces. Well *BLEEP*.
While I know this is an expensive hobby, I thought I could drop a few hundred here and there. I know my old eyepieces have some dust (not much), I was wondering if they might be the culprits. Am I expecting to much from this little, old telescope? I have seen some small refractors with ED glass and they are sharper than my scope.
Should I try updated eyepieces? With an adapter ?
The skinny is if I need any new coatings, glass, mirror etc I can't afford it. I can scrape the money for a cleaning or some eyepieces, but not both. Is there any tell tail signs that something specific might be wrong? I know these are some vague questions. Please excuse my ignorance I just want to love my telescope as much as others love theirs.

#2 munirocks

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Posted 12 July 2014 - 06:17 PM

I'd first try to isolate the problem to see if the issue lies with the eyepieces or the scope. Try the eyepieces in a different scope (of the same f/14 speed), and borrow some other eyepieces to try in your scope. How does the main mirror coating look? Does it show any deterioration around the edges?

#3 paulandrei

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Posted 12 July 2014 - 11:55 PM

Hi the mirror looks good. The front optics have a few small blemishes. Maybe you can only expect so much from 89mm. I just need to make some telescope friends in my area, and compare scopes.

#4 cbwerner

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Posted 13 July 2014 - 12:36 AM

A lot of things like this are driven by expectations and focus. If you expect more than is reasonable for the scope or are trying to do something the instrument isn't well suited for you're just setting yourself up for disappointment. That's why I think hanging with some fellow amateurs and using their scopes is so helpful - you can cover a lot of ground quickly in figuring out what you're after.

There is one pitfall to avoid in that, but it's controllable. The views are going to be great through that 16" Dob (going big to make my point ;) ), but how are you going to react to the setup, and even worse, the takedown? Does it fit your car easily? Is your schedule and your viewing habits truly going to accommodate the logistics required to truly use a larger scope?

For many the answer to those questions is yes. But there are also a whole lot who jump for that larger scope, and it ends up sitting unused in the garage after the initial thrill wears off.

That's why I cautioned in the other thread about letting the Q go too readily. It truly excels in the logistical department, from having everything you need in one small case, to a truly high build quality where everything works as it should with no compromises, to the simple beauty of the control box and it's ability to switch between finder, scope and Barlow views with 2 levers.

Now, my wife is a real bargain hunter, and will show up at times with purchases that are thoughtful but ill considered at the same time - like buying me a 4 lb. bag of a type/brand of coffee I don't drink because she thought the price was good. Well, it ain't a bargain if it's something I don't want.

That's your dilemma - you've got a real gem on your hands at a bargain (at least pre-cleaning or whatever, but likely after that as well). But it ain't a bargain if it doesn't fit what you want. Hanging with other amateurs and using their scopes will help you sort that. You should also read through the threads here and see what people do with their Q's - that will give you a better idea of how others enjoy their Qs.

To paraphrase a quip about boating, it's nice to have a big Dob or some other huge scope, but to my mind it's better to have a friend with a big scope. I get the big scope itch every now again; all it takes for me is a star party fix. I've never met an amateur astronomer who wasn't positively delighted to have others bask in the views through his/her scope.

Good luck, and I hope we'll see you back with more questions.

#5 dcriner

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Posted 14 July 2014 - 06:25 PM

Why not send it in to Questar for an overhaul?

#6 munirocks

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Posted 15 July 2014 - 05:17 PM

He's already answered that question in the original post.

#7 GR1973

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Posted 15 July 2014 - 07:26 PM

Can you post some images of the mirror and the corrector so some of Q members could estimate the situation ?

#8 paulandrei

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Posted 16 July 2014 - 12:19 AM

Hi everyone and thanks for the support. I was wondering if anyone could suggest any eyepieces that would work with this scope, and aren't too hard on the wallet. I talked to someone at questar, they told me the adapter for the slip eyepieces (1.25"?) would be $80ish. I think finding one used would be hard. Someone in this post mentioned that I need to buy f/11 eyepieces. In other posts people have mentioned a 12mm is a good useful size. I have the factory 40-80 and 80-160. I think my 80-160 is 8mm? Does anyone have any suggestions in the used eyepiece in the $150 or less range. I have seen several Meade's on eBay for $50ish, and Televue for much higher.

#9 ColoHank

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Posted 16 July 2014 - 12:23 AM

You mention in your original post that you have eyepieces. Are they the eyepieces that came with your Questar, or are they eyepieces you already owned? If the latter, I assume you have some experience observing. If that isn't the case, then perhaps image quality is being adversely affected by poor "seeing," usually due to turbulence in the atmosphere caused by wind currents aloft and convection currents from ground heating. If seeing is poor, those air currents will distort the view and make familiar objects like the Moon appear as if it's under flowing water. Poor seeing adversely affects all kinds and makes of scopes, and there isn't much you can do about it except to wait for better conditions.

If you have no experience with Maksutov telescopes like the Questar, you may also be unaware that, because the corrector (the front meniscus) is thicker and has more mass than the corrector or objective lens on other designs, it sometimes takes longer for such instruments to reach ambient temperature, and that internal air currents can substantially degrade image quality. When you plan to observe with the Questar, be sure to allow ample time for it to reach temperature equilibrium with its surroundings.

Finally, clean those eyepieces regardless of their pedigree. Deposits of dust and oily eye-gunk on optical surfaces aren't conducive to a good observing experience.

#10 Mike E.

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Posted 16 July 2014 - 05:46 AM

Hi Paul,

I recall there is a thread here listing eyepieces which work well and also come into focus with the Questar finder, perhaps someone on the forum here can provide a link.
Both Questar & TeleVue make 1.25" eyepiece holders for your Questar. The one TeleVue makes however, does not provide a diopter adjuster to focus the finder, which the Questar unit does.
Considering the internal barlow as being 2X, your 40-80x eyepiece would be 32mm, and the 80-160x would be 16mm.
We also have an older Questar which had these eyepieces, but purchased the modern Questar eyepiece holder which allows use of standard 1.25" and threaded Questar/Brandon eyepieces.
Here is a photo of your 1 3/16" threaded, the TeleVue, and modern Questar eyepiece holders.

Note: Your 40-80x and 80-160x eyepieces can also be used in other scopes when in their holder, as it is a slip fit in a 1.25" eypiece holder.

Attached Files



#11 Matt Looby

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Posted 16 July 2014 - 09:37 AM

You should be absolutely frustrated.....that's a good thing.

First step is to realize it's not the equipment that's messed up. It is the observer. One must have a qualified mentor to teach the ropes, innumerable time at the eyepiece and a simple repeatable method....

If you want to learn to observe, PM me, we can talk via phone and if you live nearby, we can meet.

Note: Do not buy any additional equipment, you are headed swiftly down the wrong path!

Regards,

Matt
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#12 Edd Weninger

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Posted 16 July 2014 - 12:43 PM

I don’t think you need to drop a few hundred of anything to enjoy your Questar. It may be old and not have the latest coatings, but I’ll wager it is still very useable.

If you have the Questar eyepieces, you will only need a 12 mm when the scope is working well, and the sky is being co-operative with good "seeing" conditions. The 12 mm will produce higher magnification, and high magnification requires a very steady atmosphere (which is a rare occurrence). The eyepieces that came with the scope are of good quality. You don't need any others.

My Questar is the smallest scope I own, but it is an enjoyable instrument that provides much pleasure. I have several other eyepieces of good quality, but have used a 12 mm very seldom. I bought my Questar in 1989, 25 years ago.

I'd suggest you learn to observe starting with the Moon. Presently, the large planets are not located where good views are possible. Many Questars came with a solar filter that will enable you to view sunspot activity (Note: do not do this unless you are certain the finder scope ALSO has the solar filter, and you know how to use it !!).

Finding other objects, such as double stars and globular clusters, will require a knowledge of the sky and how to locate things there. Understanding how to use the setting circles will get you close, but it will still require a patient search to put the desired object in the field of view using your lowest power eyepiece. The finder is the poorest feature of the scope.

Have you used your Questar in the daytime? Mine will focus as close as 11 feet and makes a nice long-distance microscope.

edit: Use the scope without flipping the Barlow lens into place. It could be a cause of mis-alignment.

#13 peashooter1982

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Posted 18 July 2014 - 08:44 PM

Good advice above regarding cooldown requirements, seeing, limitations of small aperture, etc. Is there an astronomy club in your area? Does your state sponsor a regional star party? It'd do you good to compare your Q side-by-side with someone else's. By swapping eyepieces, looking at the same objects, etc., you'd have some idea of where you stand vs a "reference" Q.

#14 Larry Geary

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Posted 09 August 2014 - 09:39 AM

Hi
I inherited a well used 69' 3.5 basic model some years ago. I have not been impressed with the proformance. I talked to someone at Company 7 about a cleaning. He mentioned that because of the age I might consider having it cleaned, and shelving it as an heirloom. He suggested I then buying a newer model with better tracking, optics, mirror, coatings, and eyepieces. Well *BLEEP*.
While I know this is an expensive hobby, I thought I could drop a few hundred here and there. I know my old eyepieces have some dust (not much), I was wondering if they might be the culprits. Am I expecting to much from this little, old telescope? I have seen some small refractors with ED glass and they are sharper than my scope.
Should I try updated eyepieces? With an adapter ?
The skinny is if I need any new coatings, glass, mirror etc I can't afford it. I can scrape the money for a cleaning or some eyepieces, but not both. Is there any tell tail signs that something specific might be wrong? I know these are some vague questions. Please excuse my ignorance I just want to love my telescope as much as others love theirs.

 

Hi Paul,

 

I can't tell from your post exactly what problem you are having with the Questar. But unless the scope was violently abused, there is nothing wrong with it that can't be easily fixed by Questar. I'm frankly shocked that Company 7 would suggest you shelve it and buy another one, because the differences would be almost unnoticeable. You have a scope that many people would love to be given, so don't do anything rash.

 

There is nothing wrong with the eyepieces that came with the scope. People prize them. You say the mirror looks fine, so it doesn't need re-coating. You say there are blemishes on the corrector, but those will not affect the views at all. There is the possibility that the scope has fallen out of collimation - I've seen one badly-collimated Questar that gave terrible views -  but Questar will take care of that during service. Unfortunately their standard service costs $450.

 

We don't know what your level of observing experience is, so we don't know if you are making rookie mistakes or not. But just in case:

 

  • Don't set up on a hot surface like concrete or asphalt.
  • Use a sturdy table or tripod to avoid image shake.
  • Don't observe objects over chimneys, buildings, or other sources that may be emitting heat.
  • Objects lower than 30 degrees altitude will usually be less sharp due to the atmosphere.
  • Give the scope 30 minutes to an hour to cool down after you set it outside.
  • Using the legs, or attaching the base to a tripod head, make sure the scope is polar aligned for good tracking.
  • On the control box, the upper-right knob changes from finder to main scope. Flip right for finder, left for main scope.
  • When in finder mode, rotate the eyepiece to focus.
  • The upper-left knob controls the barlow. Flip right for barlow, left for no barlow. The barlow doesn't work with the finder.
  • When switching to/from the barlow, you will have to refocus using the focus knob on the lower right.

 

In addition to not knowing your level of experience, we don't know what your expectations are. When I first got my Questar, I had high expectations from reading all the ads in Sky & Telescope, and I was disappointed. I placed an ad to sell it. A man who owned a 3" Unitron refractor answered my ad, and we met at his place to try out both scopes. We found that the Questar had better light grasp and slightly better resolution, while the Unitron refractor had better contrast. We both decided to keep our scopes, and I still have my Questar 29 years later. What I learned in the mean time was how to use it and what to expect from it. It has some great virtues, but it also has limitations. Its main advantage is portability - I can take a complete equatorially mounted scope capable of some astrophotography anywhere in the world as airline carry-on luggage. I've seen the C-ring of Saturn from the big island of Hawaii, and galaxies in the Virgo Cluster from a dark site in New Hampshire. It performs as well as possible for a 3.5" scope, but that is still a small scope. If portability isn't a concern, then an apo refractor of the same size will beat it.

 

Take Matt up on his offer of consultation and see what happens. Even if it ultimately isn't the perfect scope for you, it's a great option to have in hand for those times when it fits the bill.



#15 munirocks

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Posted 27 October 2014 - 04:55 PM

If the mirrors look good, your eyepieces are clean, and the view is still worse than other scopes of similar size in a side by side comparison, then it really sounds like it's out of collimation. Maksutovs are extremely robust regarding collimation, but it can happen.

 

Does anyone know what is involved in collimating a Questar? I assume you collimate the main mirror and not the corrector. There's a surveillance model on ebay without a control box, and some of the screws on the back look like likely candidates. If this is correct then you would have to remove the control box first. I think you would also need to ensure that the mirror and corrector haven't rotated in their mounts - make sure the index marks on the edges are at the six o'clock position. Can anyone else confirm my guesswork?



#16 RobertPettengill

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Posted 27 October 2014 - 06:00 PM

$450 to bring a 45 year old scope back up to snuff sounds like a deal.   I would not expect a big difference between a refurbished vintage Q and a new one.   As I recall 1968 was when Questar switched to Brandons and a 1.25" diameter diopter adapter.  If your scope has the older smaller eyepieces, it would be a good idea to update to 1.25".   You can still use your old eyepieces (with an adapter) but will be able to use many modern ones as well.  I'd get comfortable with the scope, figure out what kind of observing that you want to do with it, and then add additional eyepieces as you need them.

 

 

 

;rob



#17 DRohrman

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Posted 27 October 2014 - 06:29 PM

Hi Paul

I too am a relatively inexperienced owner of a Q 3.5, and a lot of people have helped me get used to this marvelous instrument. It is unlike my other telescopes, and in many ways superior.

So I have a few suggestions, some you have already read:

1. Go slow. Don't rush out and buy a lot of new gadgets. The Brandon's that likely came with your Q are excellent assuming they are in working order and clean. Zeiss cleaning solution and cotton balls are good for really nasty lenses, otherwise a camera lens puffer will work fine. Avoid cleaning harshly.

2. Get a manual. Read it and then read it again. Some information is intuitive and some is not.

3. Where do you live? This summer and fall in the Chicago northern suburbs the seeing has been horrible to only so-so. Contrails and clouds coupled with light pollution are the enemy.

4. Start with daytime viewing first. Even though everything will of course, be upside down, immediately you will be able to see flaws in the mirror and corrector and or the diagonals. Collimation should be handled by Questar. Not the end of the world, expensive, but essential if you wish to use the Q. By all means, Learn how to focus. The focus knob is one of the Q's few misdesigns, just be patient. Learn to focus the diopter. Switch lenses often and learn hwhat they can do in finder, regular and Barlow modes. Label the modes until you know them.

5. Then await a clear night, depending on your location. Use a Steady base or top quality tripod on which you should not lean.

6. Start on a night when the moon is out, play with focusing, lenses, in all the modes. Learn how to use RA and Dec knobs. The moon on any decent evening and a half way decent Q should be bright and crisp in detail. Learn to Avert your eyes, learn what is meant by "eye relief". Play around until you see lunar details clearly. The Q is fabulous with lunar viewing.

7. If all is well then, try some planets later this year and next winter. Do not go for the more difficult deep sky galaxies and other dim objects until you know more about the Q and know how to navigate the sky. Be assured, however, the Q can resolve most of the Messier objects...however, you will never get Hubble type views, that goes without saying I suppose. Most amateur astronomers are like everyone else, most of them are pleasant, passionate about their interest and helpful. Local clubs can be really good in this regard, and of course basic books and online apps can be very, very helpful. If you are not familiar with the nighttime sky, you are swimming up stream.

8. Learn then how to polar align the Q. And then use the RA drive (and Dec drive if you have it) to steady on more challenging objects. Then get a slip fit adapter and have fun with other eyepieces such as the magnificent TeleVues.

9. If you are still having trouble, call Jim at Questar. He is a wealth of knowledge, and will take you from there.

 

I sincerely hope this is helpful to you...don't be frustrated. I have had my moments.

Doug Rohrman



#18 RobertPettengill

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Posted 28 October 2014 - 07:51 AM

Paul,

 

Your 80-160 is a 12mm eyepiece and the 40-80 is a 24mm.  There are no eyepieces sold as f/11.  The Questar is an f/14 scope (1280mm/89mm focal ratio) with a relatively narrow field of view.  This means that simple eyepiece designs will work well in the Questar (complex and expensive eyepieces designed for fast, low focal ratio, scopes and wide fields of view will work too, but are not required).  The Televue Plössl designs for example are a nice match that come to focus in the finder and less than $150 new.  The Televue Panoptic 19mm will give a wider apparent field of view than your stock Questar eyepieces and is a favorite of many Questar owners.  You will see as much of the sky as with your 24mm, but have the magnification of a 19mm.  It will work well with the Questar finder and can be found used for  ~ $150.  You may need the Questar adapter for slip fit eyepieces as described in an earlier post.

 

I agree with the others who suggest that you work with your existing eyepieces until you are more comfortable with your scope.  With care, eyepieces are easy to clean yourself and the Questar set along with the internal Barlow is very versatile.

 

Your patience will be rewarded, the Questar can give amazing views for it's size and is so easy to move and set up that it is easy to use often.  I have an 8" scope and the Questar and use the Questar 10 times as often.  When I first got the Questar I was often frustrated because I couldn't see anything.  It's easy to get those convenient control box levers in combinations that don't make sense or have your focus too far off or leave the lens cap on (the finder works fine :-).  I made all of those mistakes and often took an embarrassingly long time to figure out what I did wrong in the dark.   After a little practice your muscle memory will kick in keep you in the groove.  The manual can be confusing - some of the figures are not labeled well, but it is essential.  If you don't have one let me know.

 

;rob

 

Hi everyone and thanks for the support. I was wondering if anyone could suggest any eyepieces that would work with this scope, and aren't too hard on the wallet. I talked to someone at questar, they told me the adapter for the slip eyepieces (1.25"?) would be $80ish. I think finding one used would be hard. Someone in this post mentioned that I need to buy f/11 eyepieces. In other posts people have mentioned a 12mm is a good useful size. I have the factory 40-80 and 80-160. I think my 80-160 is 8mm? Does anyone have any suggestions in the used eyepiece in the $150 or less range. I have seen several Meade's on eBay for $50ish, and Televue for much higher.


Edited by RobertPettengill, 28 October 2014 - 07:52 AM.







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