[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: [APML] Congrats Chris !



Chris,
 
    Working on NGC 6946...
 
    Discovered something interesting... even 1 second exposures was giving me elliptical stars... I was going nuts trying to figure this out... scope was collimated, secondary was collimated... optics were centered... what gives? It has happened to me before... never could figure it out.
 
    Turns out that the secondary was stuck in the secondary holder... I store the scope in a horizontal position during the day... somehow the secondary was getting wedged  because when I tapped around the edge of the secondary holder (on the Cass) with the back of a screwdriver, the problem vanished and I ended up with the roundest stars I have ever seen from this scope.
 
    So now I store it in a vertical position and let it cool down in a vertical position... we'll see tonight if that helps. All these years I have been fighting this thinking it was a tracking problem of some sort... sheesh...if anyone out there has elliptical stars with one second exposures... check your secondary.
 
     Tony
_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo