Go Back   IceInSpace > Equipment > Astrophotography and Imaging Equipment and Discussions
Register FAQ Calendar Today's Posts Search

Reply
 
Thread Tools Rate Thread
  #1  
Old 11-01-2020, 09:36 AM
HeavyT
Registered User

HeavyT is offline
 
Join Date: May 2019
Location: South Australia
Posts: 48
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.
Reply With Quote
  #2  
Old 11-01-2020, 10:02 AM
Merlin66's Avatar
Merlin66 (Ken)
Registered User

Merlin66 is offline
 
Join Date: Oct 2005
Location: Junortoun Vic
Posts: 8,922
It's not unusual to add weights up front to get better balance...
The Kmart wrist weights seem to work pretty well.
Reply With Quote
  #3  
Old 11-01-2020, 10:37 AM
HeavyT
Registered User

HeavyT is offline
 
Join Date: May 2019
Location: South Australia
Posts: 48
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
Reply With Quote
  #4  
Old 11-01-2020, 10:49 AM
glend (Glen)
Registered User

glend is offline
 
Join Date: Jun 2013
Location: Lake Macquarie
Posts: 7,103
Buy a Triplet, problem solved.
Reply With Quote
  #5  
Old 11-01-2020, 11:46 AM
HeavyT
Registered User

HeavyT is offline
 
Join Date: May 2019
Location: South Australia
Posts: 48
Quote:
Originally Posted by glend View Post
Buy a Triplet, problem solved.
Indeed! And on the cards
Reply With Quote
  #6  
Old 11-01-2020, 01:13 PM
Wilso
Registered User

Wilso is offline
 
Join Date: Nov 2016
Location: Adelaide
Posts: 427
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
Reply With Quote
  #7  
Old 12-01-2020, 04:15 PM
HeavyT
Registered User

HeavyT is offline
 
Join Date: May 2019
Location: South Australia
Posts: 48
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?
Reply With Quote
  #8  
Old 13-01-2020, 02:30 PM
Joshua Bunn's Avatar
Joshua Bunn (Joshua)
Registered User

Joshua Bunn is offline
 
Join Date: Oct 2011
Location: Albany, Western Australia
Posts: 1,478
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.
Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 05:46 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement