Easy way to measure flexure

[Moon]

I want to share this great idea from Sander on the QHY yahoo group.

http://deepskystacker.wikispaces.com/Measuring+differential+flexure

It's the simplest way I have seen to measure flexure.

[Moon]

(I hope this is the right forum for this post)

Some of my results using this method:
ED127 over 1 hour has Dx=3.17 and Dy=6.31
Old 8" SCT with no mirror lock over 23 minutes has Dx= 19.12 and Dy=40.12 :eyepop:

[Lester]

Thanks for that James, it may be very useful when I get back into DSO imaging.

Slight problem here for the past 3 months,= cloud.