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Old 06-03-2018, 07:27 AM
Mick1 (Mick)
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Counter weights

I recently purchased a Skywatcher EQ3 mount which came with 2 counter weights (3.4 & 1.8 Kg), do I need to fit both counter weights or can I use either one as long as I can achieve balance with all accessories attached.
I have read the assembly manual but all it says is to fit counter weights, it's a bit vague.
At the moment I have the 3.4Kg weight attached and the telescope is balanced ok. Can someone more experienced shed some light on this please?
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Old 06-03-2018, 07:29 AM
Imme (Jon)
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Just use whatever weight....or weights you need to achieve balance and you’ll be fine.
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Old 06-03-2018, 09:43 AM
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sil (Steve)
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As long as you're balanced thats all that matters. Mounts are often supplied with several weights to allow balancing of different sizes of telescopes and addon gear people might use. So if you add a camera for example the balance will shift and you may need the extra weight to rebalance the setup. Be thankful its there, postage on a weight is hideous if you found later you needed extra.
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Old 07-03-2018, 08:48 PM
PhilTas (Phil)
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The idea is to position the weight closer to the rotation axis. So you may be able to achieve balance with the heavy weight in close, the lighter weight might also work out further. But the closer weight (even if it is heavier) will be easier for the motors for tracking (if you are using tracking drives).
If you are tracking with the slow motion controls, keeping the counterweight in close is still better, with less force on the worm, and potentially less subject to vibrations in wind or if bumped.
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Old 08-03-2018, 12:00 AM
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Rkonrad (Richard)
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If you purchase the mount on its own then it depend on what scope you place on it but generaly I prefer the counter weight as close as possible to the mount , put the center of gravity more in the middle and thus a more stable set up , however this can make the scope set up heavy if you want to move it around
I am not sure what an EQ3 mount is , skywatcher here are EQ3-2 , or EQ5 etc
Lots of so called EQ3 mounts on the market that just dont work, is yours is similar to a CG 4 mount , if so then its a EQ 3-2
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Old 08-03-2018, 07:05 AM
Mick1 (Mick)
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counter weights

Thanks everyone for your input, I should have mentioned what I have attached to the mount which is a Skywatcher 102 x 1000 achromat refractor and the mount is the Skywatcher EQ3-2.
I have the bigger weight about half way along the counter weight rod and the set up is balanced ok.
What I have found is the set up is very touchy the image shakes a fair when I touch the scope and gets worse with higher power eyepiece ( I understand why this happens). If I move the heavier weight closer to the mounting point which has been said will increase stability I should then be able to position the smaller weight to achieve balance. Would that be a fair assumption?
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Old 08-03-2018, 10:38 AM
Saturnine (Jeff)
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Hi Mick
This is probably what you don't want to hear but an EQ3-2 is , realistically, undersized for an 102 x 1000 refractor and the aluminium tripod usually supplied isn't the best for damping vibrations. Wouldn't matter how well the scope is balanced, how many counterweights and where they are set on the shaft if the mount is struggling. Any bump or touch of the focuser will take several seconds to settle, the scope would be much steadier on an EQ5.
Moving the large weight close to the top of the shaft and using and adjusting the position of the smaller weight to achieve balance will help a little but not a miracle fix.
I still don't understand why the manufacturers and retailers, in a lot of cases, under mount the telescopes they sell. Only causes frustration for the users and could possibly turn them off the hobby.
If you're skilled with hand tools you could construct heavier wooden tripod legs to put the mount on, will help noticeably.
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Old 09-03-2018, 01:32 AM
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Rkonrad (Richard)
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Glad you have a EQ3-2 mount its a good mount and will handle your 102 F10 scope , the problem could be the tripod , the one to use is the S/S one which can be purchased and not too costly , if yours came with the alluminium one then its on its limit, I could post some photos but have just joined so have to wait a while
By the way ignore my price comments as I am from RSA
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Old 09-03-2018, 06:52 AM
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Quote:
Originally Posted by Saturnine View Post
.... I still don't understand why the manufacturers and retailers, in a lot of cases, under mount the telescopes they sell. ....
The answer to this is money... smaller mount cost less so the profit from sale of the whole is larger.

Last edited by bojan; 09-03-2018 at 12:29 PM.
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Old 09-03-2018, 12:07 PM
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sil (Steve)
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Quote:
Originally Posted by bojan View Post
The answer to this is money... smaller mount cost less so the profit from sale of the whole is larger.
Exactly, you've got a tripod, a mount, an OTA, eyepieces to make up a "telescope" and while these days the OTA optics are generally good, they save money on the other items instead. Supplied eyepieces are typically a letdown as is the tripod. So as you learn and use your telescope post your progress and what letdowns you have and we can help you make upgrade or stopgap solutions.

The question of wobble and vibration through the tripod can be reduced by hanging a heavy mass in the middle underneath the tripod. Some have a small hook in place for this purpose. if not gerry rig something , ideally you want to hang from the solid part the tripod legs are bolted to, just dont hang anything from a part thats meant to move, its to keep the legs as rigid as possible. Even a breeze can be picked up by the legs and amplified up through all the equipment to wobble things.

Also as you use smaller eyepiece sizes you are increasing magnification and this can make views wobble too. This is due to atmospheric "seeing". Then there's cooldown issues common on Newtonian / mirror style telescopes, where the temperature of the thick mirror takes time to cool to the outside ambient temperature and during this period you also can experience a swimmy/wobble effect in the eyepiece from different temperature air currents moving across the face of the mirror.

So you'll learn there are multiple ways problems can occur and therefore multiple ways to address them. Ideally itd be great to be able to afford the better components but in practice we often take incremental steps in that direction as time and money allows etc.
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Old 09-03-2018, 09:02 PM
yoda776 (Matt)
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I would agree with the thought on why manufacturers undersell their scopes by supplying below par eyepieces and mounts. My friend got a scope and a cheap eq mount and has never really used it as he could not figure out the mount. Personally i found Alt-az a good start before moving onto an EQ mount.

An EQ 5 would be good in this case + 1 in agreeance or an Orion Skyview Pro mount like I have with the motor drives seems to work really well. It is a great mount and tripod set for a good portion of my gear.

Quote:
Originally Posted by Saturnine View Post
Hi Mick
This is probably what you don't want to hear but an EQ3-2 is , realistically, undersized for an 102 x 1000 refractor and the aluminium tripod usually supplied isn't the best for damping vibrations. Wouldn't matter how well the scope is balanced, how many counterweights and where they are set on the shaft if the mount is struggling. Any bump or touch of the focuser will take several seconds to settle, the scope would be much steadier on an EQ5.
Moving the large weight close to the top of the shaft and using and adjusting the position of the smaller weight to achieve balance will help a little but not a miracle fix.
I still don't understand why the manufacturers and retailers, in a lot of cases, under mount the telescopes they sell. Only causes frustration for the users and could possibly turn them off the hobby.
If you're skilled with hand tools you could construct heavier wooden tripod legs to put the mount on, will help noticeably.
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Old 25-03-2018, 05:22 PM
N5SE (Sal)
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as long as you achieve balance one counter weight is fine
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