Walking noise with alt/az mount

[psy1280]

I'm trying to minimize walking noise. I'm using an Evolution SCT 8", alt/az, applying a master along with a dark, doing EAA (and therefor I cannot dither). Two questions:



1.) What's the best way to approach my quest to minimize walking noise, i.e., higher gain shorter exposures or lower gain longer exposures?

2.) Why is the walking noise much more apparent on the right one-third of my images? Always on the right side.



Any and all suggestions greatly appreciated

Joe

[admin]

Hi,

The only thing I can think of why it might be worse on the right-hand side is if the camera/scope is not quite pointing at the point that the mount is tracking – that would mean that the field rotation that is always going to happen with an Alt/Az mount might be centred at a point either somewhere to the left of the frame (and the worst walking noise is on the right away from the centre of rotation) or perhaps somewhere to the right of the frame (and the worst walking noise is nearest to the centre of rotation). If you take a single longer exposure that gives you enough star trails to spot the centre of rotation you might be able to see if this idea has any truth to it.


Cheers, Robin