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Old 11-01-2020, 09:36 AM
HeavyT
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How to achieve Declination balance

Hi folks

I didn't think it would be possible to imbalance my 900mm f9 doublet any further than hanging a full frame DSLR off of it, but I've done it.

Turns out an astro cam with filter wheel, oag and reducer/flattener weighs more than a dslr, plus all the cables.

I've always had to slide the tube further forward in the rings than I was comfortable with, and now I've run out of play.

Should I buy some Velcro "wrap-around" weights to put at the objective end of the scope to achieve Declination balance without the flexure risk?

Or do I need a ridiculously long dovetail so I can push the whole lot further forward (this seems a precarious scenario)?

I can't think of too many cons to the Velcro weights idea, provided they are tight enough to not move around.

I can't be the first person to have faced this and yes I know a larger scope would potentially solve my problem

Thanks in advance for your suggestions! Clear skies.
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  #2  
Old 11-01-2020, 10:02 AM
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Merlin66 (Ken)
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It's not unusual to add weights up front to get better balance...
The Kmart wrist weights seem to work pretty well.
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Old 11-01-2020, 10:37 AM
HeavyT
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Quote:
Originally Posted by Merlin66 View Post
It's not unusual to add weights up front to get better balance...
The Kmart wrist weights seem to work pretty well.
Cheers mate, just spotted those online this morning and am off to get some
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Old 11-01-2020, 10:49 AM
glend (Glen)
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Buy a Triplet, problem solved.
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Old 11-01-2020, 11:46 AM
HeavyT
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Originally Posted by glend View Post
Buy a Triplet, problem solved.
Indeed! And on the cards
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Old 11-01-2020, 01:13 PM
Wilso (Darren)
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Some scopes have an offset mounting plate for this, my fsq85 is one, works well with the camera. Losmandy have some long d series dovetail plates that should get you out of trouble or add a small counterweight to the forward underside of the dovetail.
Good luck
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Old 12-01-2020, 04:15 PM
HeavyT
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Quote:
Originally Posted by Wilso View Post
Some scopes have an offset mounting plate for this, my fsq85 is one, works well with the camera. Losmandy have some long d series dovetail plates that should get you out of trouble or add a small counterweight to the forward underside of the dovetail.
Good luck
Thanks, I tried this and it didn't give me balance so I've had to wrap 2 x 1kg weights round the tube close to the rings.

Am I likely to warp my tube over time?
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Old 13-01-2020, 02:30 PM
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Joshua Bunn (Joshua)
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Try bolt something to the objective side of your declination dovetail, and have a sliding counterbalance on there, no issues with more weight hanging off the tube.
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