Celestron 102-660 Refractor wobbles on mount

[STGZR_102_NE]

Hi there,

As additions to the standard 25mm eyepiece that came with this Celestron 102/660 Refractor, I purchased a barlow 2x and a 9mm eyepiece.

Brings the scope up to ~140x   Scope is mounted on an AZ tripod.

Went out to look at Mars the other night and found that just touching the focuser made the whole scope wobble and in many cases pushes the scope off target, taking a few minutes for me to find it again.  Once I get it fixed, don't dare to even touch the eyepiece with my eye for fear it will go off again.  I think the tripod design may not be strong enough for the weight and length of this scope.  Not a problem with low magnification below 50x.  But quite a challenge above 100x.   I'm guessing this may be a common issue with scope kits?  Any suggestions or recommendations would be welcome.

Thanks!

STGZR_102_NE

[RT65CB-SWL]

You could...

1. add some additional weight on or under the eyepiece/accessory tray, assuming it has one. 
2. suspend additional weight from the mount head.
3. do not fully extend the tripod legs.

[Ricochet]

Which exact tripod/mount is it mounted on? The fact that it is moving when you touch the focuser suggests that at least one of your clutches is a little too loose. There should be a point where you have enough friction that it doesn't move unless you want it to but where it is still easy to move smoothly.

[Ruud]

All of the above. But I would start with tightening the bolts at the top of the legs and then anything else that can be tightened.

[Cosmic Geoff]

We could advise you more if you told us what mount/tripod you are using. The expedients suggested above will help, but if you want an order of magnitude improvement, you will have to buy a better mount/tripod.  An AZ-4 or EQ-5 with tubular stainless steel legs, for instance, is like scaffolding when compared with the budget or portable-style aluminum-legged tripods.

A short focal length achromat is never going to be a great planetary scope, so you might think of biting the bullet and getting a long focal length instrument (e.g. a Maksutov) on a more rigid mounting.

[STGZR_102_NE]

Thanks everyone!

Celestron doesn't have a model number for this mount.  Which tells me something right away.

I'll upload a screen-shot of it - and try the suggestions.

But I think Proto Star's comment on using this scope for planetary views is correct.  Theoretically, the max magnification for this scope is 200x.  But I suspect in most instances 100-140 is going to be its best magnification for best visual clarity.  I've been looking at Maks.  And I'm wondering about the possibility of getting a used unit.  And also what diameter for planetary views.  I've been looking at simulated views of Saturn at various magnifications.  A mag of 350x is of course a very pleasing view of the planet.  And that would require an 8" Mak.  But I'm wondering if that magnification would then be unrealistic for most "seeing" situations?

On the tripod - I do have my own welding setup, so I could consider building a beefy mount.  Something that would take two men to carry!  :-]

 

[Cosmic Geoff]

An AZ-4 (steel legs) would be a more rigid off-the-shelf replacement for that mount. (no slow motions though). A manual alt-az mount should be within the capabilities of a keen do-it-yourselfer (check the DIY Astronomer section in this forum). It doesn't have to be heavy enough to require a two-man lift. ?  Bear in mind that for planetary viewing an equatorial mount with RA drive would be more convenient.

As for a replacement scope for planetary viewing, you'll get a variety of advice.  Maks, long focal ratio Newtonians, SCTs and apochromatic refractors of various sizes have all been proposed in past threads on this forum. An 8" SCT is pretty good. What's your budget? 

[STGZR_102_NE]

Thanks!   I'll check out the DIY section as you suggest.  I think I want to get alot more educated than I am before I go for another scope.  I've ordered Richard Berry's " Build your own Telescopes" and I've been looking at glass dealers.  I'm a little surprised at the cost of buying glass primary mirrors.  The prices seem to be around 90% of what one would pay for a complete unit new the same diameter.  I was wondering if Celestron or Orion would sell mirror replacements. 

That would obviously steer me in the newtonian or dobsonian route.   A used Skywatcher Skymax 150 Mak ATO in the $350 ball-park might be a good fit, if its possible to pick up one for that price.  But again I think I would be wise to get  more educated first.  I've reached out to a local group in our state via email but no response yet.  They plan sky watches and clear-sky permitting that might be a good association for me to connect with.

I'm also wondering about what an attached camera can add to the mix.  If a camera can capture a longer exposure of an object, (longer than the eye) which then can be digitally magnified with sufficient clarity.  Is it possible that one who is strictly limited to what one's eye sees in the eyepiece, will end up making 5 times the financial investment for that privilege - compared to capturing the image to digital?

[Cosmic Geoff]

11 hours ago, STGZR_102_NE said:

I'm also wondering about what an attached camera can add to the mix.  If a camera can capture a longer exposure of an object, (longer than the eye) which then can be digitally magnified with sufficient clarity.  Is it possible that one who is strictly limited to what one's eye sees in the eyepiece, will end up making 5 times the financial investment for that privilege - compared to capturing the image to digital? 

Since you ask,  I personally have found visual telescopic views of the planets somewhat anti-climactic, and have resorted to planetary astrophotography to get more out of my telescopes. I can see more in my processed images than I ever could directly.  The extra outlay (modest compared with what can be spent on deep-space astrophotography) for a USB video camera and ADC is worth it, IMHO.  You'll need a suitable mount that will track the planets stably and allow fine adjustments of aim. 

If you look in the 'Planetary Imaging' section of this forum, you will see what kind of image can be achieved, and with what equipment. 

[STGZR_102_NE]

Awesome!  I was suspecting the same!  Thanks so much for the excellent advice.  Very much appreciated.  :-]