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What Is the Ideal Counterweight?

Askar 130PHQ ZWO AM5 Equipment Equatorial Mount Guiding
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Jerry Gerber avatar
Jerry Gerber avatar
I am going to be using the Askar 130PHQ refractor on the ZWO AM5 mount.   
I know that there's a trade-off between mount stability and guiding. 

I want to understand what the best counterweight would be for this setup.  The scope and accessories weigh around 32 lbs. 
I bought a 10 lb. counterweight (plus about 1 lb. for the shaft) but am wondering if a 5 lb. counterweight would be better. 
How do I test this and how do I determine the best place on the shaft to put the counterweight?

Rather than give me a complex mathematical formula or equation, I prefer real-world experience if anyone has solved this problem so that guiding is under .7 on both axis and the tripod/mount is balanced.  I am also putting weights in the center pouch of the tripod as well.

Thanks for any insight, deeply appreciated!

Jerry
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Geoff avatar
Geoff avatar
Quick answer: a heavy weight close in is better than a light weight further out.
Jerry Gerber avatar
Jerry Gerber avatar
Geoff:
Quick answer: a heavy weight close in is better than a light weight further out.

Thanks Geoff, that's useful to know..
Nick Grundy avatar
Nick Grundy avatar
Geoff:
Quick answer: a heavy weight close in is better than a light weight further out.


Geoff, I assume this is because of possible flex in the counterweight shaft? vs the total payload on the mount/tripod

Just curious why that is
Jerry Gerber avatar
Jerry Gerber avatar
Nick Grundy:
Geoff:
Quick answer: a heavy weight close in is better than a light weight further out.


Geoff, I assume this is because of possible flex in the counterweight shaft? vs the total payload on the mount/tripod

Just curious why that is

Good question Nick,,  I'd like to know that too.
John Hayes avatar
John Hayes avatar
Go to 49:36 of this presentation:  https://www.advancedimagingconference.com/articles/secrets-long-focal-length-imaging-john-hayes


There is a discussion of mechanical stability including where to put your CWs and why.

John
Nick Grundy avatar
Nick Grundy avatar
John Hayes:
https://www.advancedimagingconference.com/articles/secrets-long-focal-length-imaging-john-hayes


so apparently i'm shopping more counterweights

thanks John, that was a great help. (ended up watching the whole thing)
Jerry Gerber avatar
Jerry Gerber avatar
John Hayes:
Go to 49:36 of this presentation:  https://www.advancedimagingconference.com/articles/secrets-long-focal-length-imaging-john-hayes


There is a discussion of mechanical stability including where to put your CWs and why.

John

Thank you so much John for posting the link.  I bookmarked it and will be watching it repeatedly.

I've decided, due mainly to time constrains and seeing conditions to limit my astrophotography to 1000mm focal length using two refractors, a Skywatcher 100ED and an Askar 130mmPHQ.    

Being an amateur who just wants to take the best images I can with focal lengths from 358mm to 1000mm,  I think it will make imaging a bit easier and more enjoyable. 

 Your sense of humor really made me chuckle and the image of 3 telescopes on top of each other on one mount  was hilarious...

Jerry
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John Hayes avatar
John Hayes avatar
I'm glad that you guys found that presentation useful.  It's a talk about "long focal length" imaging but in reality, most of it applies to pretty much all kinds of imaging!

John
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