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Improving shaky newb visual experience

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#1 jacobm3

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Posted 19 February 2019 - 09:00 AM

I just got an Apertura AD8 as my first "real" telescope after observing on and off with binoculars and a tiny reflector many years back. I've had it out a couple nights and I've run into a frustrating challenge.

 

My hands and face are shakier than I realized. Every time I touch the focuser (even the fine adjustment knob), the image bounces all over the place and it takes several seconds to settle down. Focusing shake isn't a big deal until I change eyepieces again, but I frequently bump the eyepiece as I'm trying to get close enough to get the wide field view with my eye near the glass. I don't wear glasses. I can settle in and see a lot with a stable image, but keeping a stable image is really hard. Dealing with a constantly shaking image is super frustrating.

 

I bought a night mask to try to improvise an eye patch so I can keep my non-dominant eye open to minimize facial twitching and strain. So far that's a bust, but I have a better "3D" option on order. 

 

Tracking adjustments at higher magnifications are difficult because I frequently overshoot and each adjustment restarts the shake->settle process.

 

Here's my current setup -

Apertura AD8

Flocked with velvet opposite focuser

Stock 2" 30mm, 1.25" 9mm plossl eyepieces

Oberwerk 23.9mm eyepieces from my binoculars (great eyepieces, feel wider than my ES 82 degrees, even though they're only ~60)

ES 82 degree 14mm eyepiece

Telrad finder, stock RACI finder

Variety of Harbor Freight magnets to balance the OTA (2-3lb)

I live in a Bortle 8-9 area in Houston suburbs. I can see the main 7 stars of Orion on a clear night unaided and the Orion nebula looks like a small black and white cloud with the AD8. 

I sit on a mechanic's pneumatic adjustable roller chair which puts me at a good height. 

 

I'm considering making a few changes to improve my experience - 

- longer relief eye pieces so I can get the immersive wide angle experience without bumping the eye piece

- bigger, heavier scope, possibly with larger diameter altitude friction surfaces to minimize spring effect, maybe the ES 10" tube dob or the ES 12" truss dob (I have a 10% off ES coupon that expires tomorrow). I want something that will still fit in the trunk of my Camry, or backseat, worst case scenario. The 12" appeals to me because of the portability and I'd leave it assembled in the house and set it out to cool ahead of time on evenings that will be clear. 

- I'd really like to figure out an option to add a fine adjustment mechanism to a stable dob base so I don't have to constantly overshoot when I make corrections.

 

I can see now how this gets expensive quickly. I want something that gathers a ton of light for easy visual observing and is rock solid to compensate for my over-caffeinated, shaky self. 

 

Would longer relief eye pieces make a significant improvement, should I jump straight to the ES 12", or is the only way to fix this problem to spend an obscene amount of money on a GEM mount that can stabilize a big scope?

 

Is the ES 12" a more stable platform? Intuitively it seems the larger diameter teflon pads and alt structure would settle faster than a small diameter bearing/clamp system.

 

Any insight or guidance is appreciated.

 

Thanks!

Jacob

 

 

 

 

 

 



#2 Araguaia

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Posted 19 February 2019 - 09:38 AM

At first, there is little you can do but use lower power.  We start out literally shaking with excitement, and also with doubt: will I find my targets?  Is this good focus?  Would the other eyepiece be better?  All this generates tension.  Plus, you are trying to sit still in all sorts of unfamiliar and unergonomic positions.  

 

With time, your body develops muscle memory and strength in the appropriate places.  You get better at all the little tasks of observing, so they don't generate any tension.  You learn to find good focus and leave it alone.  You learn, and are able to, place your pupil at the right position without touching the eyepiece, except for a light brush of the eyebrows once in a while to pin down its position as you track.

 

How to speed that up?  Practice, of course.  Observe.  But take frequent breaks - the learning curve reverses if your body gets fatigued or achy.  Do some naked-eye observing every few minutes or so.

 

As for mounts: I don't know how yours is, but our 12" Lightbridge came with an awful particle board mount.  Making a simple new plywood mount for it got rid of most of the shaking.  Now, of course, I found that the OTA itself shakes a bit... ultimately, you need to condition your body to not touch the scope while observing. 



#3 SeattleScott

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Posted 19 February 2019 - 10:03 AM

A chair helps keep you steady when looking through the eyepiece. So it can make a big difference to the extent that YOU are the problem. Won’t do anything to fix a shaky scope though. 1-2 seconds of vibrations from focusing is fairly typical. A fine focus knob can reduce that, but hard to rely just on fine focus when switching eyepieces.

Scott
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#4 jacobm3

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Posted 19 February 2019 - 11:32 AM

The AD8 does have a fine focus knob.  The most frustrating source of shakes are:

1. bumping the eyepiece when I try to get close enough for the immersive wide field view. I trimmed the eyelashes in my dominant eye because the eye relief on the ES eyepiece is so short I was constantly pressing my eyelashes against the glass in order to see the full 82 degree apparent field of view. 

2. constantly overshooting tracking adjustments

3. accidentally bumping the scope when moving between telrad, RACI and main eyepiece

 

I do get a lot of aches and body tension from holding positions that I'm not used to. Warmer (and less bulky) cold weather clothing could help too. It sounds like more practice is the common recommendation.  

 

Thanks!


Edited by jacobm3, 19 February 2019 - 11:33 AM.


#5 Vondragonnoggin

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Posted 19 February 2019 - 11:43 AM

The AD8 does have a fine focus knob.  The most frustrating source of shakes are:

1. bumping the eyepiece when I try to get close enough for the immersive wide field view. I trimmed the eyelashes in my dominant eye because the eye relief on the ES eyepiece is so short I was constantly pressing my eyelashes against the glass in order to see the full 82 degree apparent field of view. 

2. constantly overshooting tracking adjustments

3. accidentally bumping the scope when moving between telrad, RACI and main eyepiece

 

 It sounds like more practice is the common recommendation.

1. There are many long eye relief eyepieces available. Even in widefield

2 & 3 - you’ve already mentioned it. Practice.

 

Remember to breath and be conscious of trying to relax while viewing. Seated observation might help as mentioned.

 

Those 82° eyepieces are nice but you can center views and use the extra wide part for peripheral vision. If watching an object drifting through the view for longer observation between nudging the scope, the breathing factor and practice of minimal relaxed movement while just barely rolling your eye to accommodate the drifting view will help.



#6 SeaBee1

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Posted 19 February 2019 - 11:57 AM

It sounds like most of your issues will be solved with practice, as others have mentioned. The issue with overshooting the target, jerky movement, etc... that are scope associated will be helped SOME with practice, but having a scope that performs mechanically is preferable. Small alt bearings are a hallmark of off the shelf scopes, typically. Many have some form of tension adjustment to make the action reasonable enough, but proper bearing size and friction material is the real answer. ES is addressing that with some of their recent offerings.

 

I have read good reviews of the Apertura series. It should be adequate with practice.

 

Good hunting!

 

CB



#7 gnowellsct

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Posted 23 February 2019 - 03:23 PM

Well, this is a common issue for budget priced equipment.  It is true that the dob mount is the most stable inexpensive mount, but that does not make it stable and easy to use in an absolute sense. It means that you're better off than with something like this.  

 

So two points.  First, you have to be aware that there are mounts out there that will be stable and will have no focus shake, even if you have a diagnosed nervous system illness that makes you shake.  Second, these same mounts will keep your view steady even if you bump the eyepiece.  So you should know that these options exist, even if you don't want to go looking for or pay for one at this time.

 

Second, there are a large number of people who make significant modifications (to trunions, to the azimuth pad at the bottom of the scope, etc.) on these budget priced dob-Newts precisely because of the issues you describe (and balance).    I have not personally myself done that but I can tell you some dobs nail these issues and get it right and some don't.  A good friend of mine has finally got his ten inch truss dob stable and smooth in almost ever respect:  azimuth, altitude, and holding balance with different oculars.  

 

I have two very good German equatorial mounts and have gotten used to steady views and precise control of their movements.  I understand the issues you're talking about because I see them on other scopes at star parties.  But not all scopes.  Some people, for whatever the design, resolve to get the problem dealt with.  Some shell out for fancy alt-az mounts for their refractors, some for fancy German equatorials, and some, as I have just mentioned, make redesigning and replacing defective parts on their dob scopes a major priority.  If you go to the REFLECTORS section and ask for links to projects for improving your dob mount, I'm sure they'll have a few suggestions.

 

Greg N



#8 rowdy388

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Posted 23 February 2019 - 03:42 PM

The dob mount is known for its stability. However it moves to wherever you point it. You 

can stiffen up the movement by tightening the adjustment knobs. You want the mount to 

be stiff enough to resist swinging too easily yet have enough sticksion to feel precise when

you do want it to move. 

 

I notice sometimes someone new to telescopes will want to lean on it to steady themselves.

Not good. A good astonomy chair is the fix for that....and practice.


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#9 kfiscus

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Posted 23 February 2019 - 04:22 PM

As just mentioned, getting the correct tension on your dob base's two bearings is important.  On the Apertura, you can crank both down fairly tightly.  My Zhumell (same manufacturer as yours) is tightened enough that my OTA doesn't shift position with EP changes at any but the lowest altitudes.  My tube is well-balanced and the tensions of both motions are about the same, making target acquisition easier.

 

Like others have said, practice will make your sessions less frustrating.  Let us know how it's going.


Edited by kfiscus, 23 February 2019 - 05:43 PM.



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