Quote:
Originally Posted by gregbradley
Thanks Josh. Looks to be almost perfect but no longer made. Also too thick. I only have 8mm to spare.
Thanks Charles. Perhaps I should make my own.2 plates with adjusting grub screws may do it. The lacking out is working but I think th eflex is slightly variable with the angle but not by much.
Greg.
|
Quote:
Originally Posted by gregbradley
Thanks for that Lewis.
Hi Raki. Thanks for that. I'll check that out. Astrodonb has a zero length adapter for the MMOAG?
Thanks Rally. It appears to be at the junction of the filter wheel and the adapter to the MMOAG. That adapter is only 2mm thick. If I grab the camera and flex on it I can see some slight movement under stress at that point. Raki's suggestion may be spot on. Definitely not the mirror as I have gotten perfect round stars to the corners many times.
Greg.
|
If you ask Ashley of preciseparts he will know about it as he already made a few including mine. He may initially complain that its a bit risky and stuff but i think its quite ok. This way the whole body of the Moag is supporting the weight and pressure is spread out on a larger area compared of having a adapter sticking out in between.
But if the tilt is constant on different part and orientation it might well be coming from somewhere else.
This is overall an interesting area. For example when I got my 3nm filters from Astrodon I saw that their edges were blackened with paint. My initialy thought was would they still sit "Perfectly square"? I don't know and thankfully I don't have a f 3.8
scope. Overall I don't think its coming from Scope or the CCD itself. So it can be from anything else in the imaging train and it can be hard/expensive to figure out what exactly is causing it. I believe Peter Ward once posted something on how he could measure required shimming thickness based on some calculation derived from auto focusing. I know he uses quite high end component like you so does that indicate tilt is unavoidable time to time when you have few items sitting in between? One thing for sure once you start getting perfect stars in all corners you would be reluctant to touch it.