Quote:
Originally Posted by RickS
Hi Colin,
Increasing the spacing pushes the focal point further towards infinity on the lens scale for all the lenses I have tested. I'm working on the assumption that I'll get the flattest field when the lens scale matches the actual distance and that seems mostly correct. Adding filters seems to complicate things. Spacing that works well for the Ha filter doesn't always do so well with the other filters. Things get tricky at the focal ratios where I have been playing!
Cheers,
Rick.
|
Thanks Rick. I think I have another 0.5-2mm that I need to add then. I'm pretty close but I'd like to get it as close as possible. As my Astrodons are all 3mm thick I wouldn't have thought that different filters would cause issues. I have done some RGB imaging and my only "issue" seemed to be blue bloat at F/4... Along with tilt caused by my mounting
Might get a clear night on Wednesday night to do some playing.