Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Help with balancing a 6inch evolution with a DSLR

  • Please log in to reply
4 replies to this topic

#1 Napster

Napster

    Lift Off

  • -----
  • topic starter
  • Posts: 4
  • Joined: 05 Feb 2021

Posted 23 February 2021 - 09:30 AM

So my friend bought a camera adapter for a Sony DSLR for his 6 inch evolution. With the camera installed the tracking stoped working. I tried sliding the scope all the way forward on the rail and it was still to heavy on the camera end. When I released the clutch the camera dropped to the bottom.

The mount moves in high speed but when it gets to the slower speeds it won’t move up which ends up throwing of the alignment.

Any ideas on how to solve this? I am thinking adding small weights to the front but don’t know how I am going to mount them.

#2 Couder

Couder

    Viking 1

  • *****
  • Posts: 862
  • Joined: 24 Feb 2014
  • Loc: Mansfield, Missouri in the Ozarks

Posted 23 February 2021 - 09:51 AM

Loosen the lock on the axis, and add weight on the other end of the tube till the camera is no longer the heavy end - you can add weight even by tying a small rope and hanging weight on it till you see how much you need. Then, you can figure out how to add that much weight in a different form, such as washers on a rope surrounding the tube, a heavy duty plastic tube filled with something wrapped around the tube, or a weight system designed for the scope. Remember to add weight so one side of the tube is not heavy. (Something like adding 1/2 the weight on opposite sides of the tube so it will be balanced.) You'll want to make it easy to remove, so you can look through the eyepiece.



#3 Noah4x4

Noah4x4

    Skylab

  • *****
  • Posts: 4,156
  • Joined: 07 Apr 2016
  • Loc: Colchester UK

Posted 23 February 2021 - 04:37 PM

Why do you need it to be balanced? It is a sufficiently powerful Alt-Az. If the tracking has stopped working, consider another diagnosis.

The 6" Evolution mount is exactly the same mount as used for the 8" and 9.25". Only the tripod differs. Given the surplus load capacity, the motors and tracking will be fine with a 6" OTA even when not balanced.

I have the 8" OTA Evolution and I front load it with Hyperstar and Atik Horizon camera, far greater weight than a DSLR. My OTA is fully forward to permit me to switch to rear mounted ASI294mc so that it will go to the zenith at f/6.3. Despite an even greater weight and more significant lack of balance my Evolution handles this fine. Balance is only critical on GEM mounts or where an Alt-Az nears load capacity, and with a 6" OTA and DSLR that is nowhere near that.

EDIT
Tracking only commences after completing an alignment. Is that the problem? .

Edited by Noah4x4, 23 February 2021 - 04:41 PM.


#4 Napster

Napster

    Lift Off

  • -----
  • topic starter
  • Posts: 4
  • Joined: 05 Feb 2021

Posted 23 February 2021 - 08:15 PM

No it tracks fine with the eyepiece installed. I can get the scope to move fine at high speed with the camera but at the slower tracking or fine adjustment speed it stops moving up even if I hit the button.

When I release the clutch with the eye piece the system stays where it is pointed. With the camera installed it swings the camera down. I guess I am just assuming that the imbalance could cause the mount to not track correctly in the slower drive setting.

I did also check the battery from my phone. It said it was high when I started and was at medium when I ended a few hours later.

#5 Noah4x4

Noah4x4

    Skylab

  • *****
  • Posts: 4,156
  • Joined: 07 Apr 2016
  • Loc: Colchester UK

Posted 24 February 2021 - 02:10 AM

Do you really mean "tracking"?

At very slow SLEW speeds (where using direction buttons), they are so slow that it will appear that the scope isn't moving. But that isn't tracking.

Tracking means the scope after an alignment is automatically moving at a constant 15° per hour to compensate for Earth"s rotation. That too is so slow you won't notice it, unless left for a good few minutes given that is merely 1° rotation every four minutes.

Yes, release the clutch and an unbalanced OTA will swing upright.


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics