Hi all,
Been having problems with my refractor since purchase from Bintel.
Bintel have been helping but i am at a bit of an impasse as to where to go next.
The scope is a Meade 5000, 80mm triplet.
A few of the guys at Bintel had a look at my images and determined that the fault is that the image plane is tilted.
So today i took my focuser apart (standard Meade focuser) and checked as much as i could to see if there was any tilt in any of the items.
Things checked:
- Focuser tube is perpendicular to the eyelet (it is).
- Focuser flange is equal in distance around the circumference of the scope to the dew shield.
- Made sure all eye pieces (etc) sit flush with the focuser. They do
- The focuser is attached to the flange properly. The focuser used is a screw-type that screws into the flange, and the flange screws into the tube. It's hard for it to not sit properly.
I then threw my laser collimator into the eye piece socket. Made sure it was perfectly flush - not 1mm higher on one side.
I then put a piece of paper in front of the scope, found the middle of the scope and turned on the laser. This is the result:
http://core-au.net/astro/camera/IMGP0068.JPG
It's a good 10mm out (give or take).
Can also be seen in this image:
http://core-au.net/astro/camera/IMGP0069.JPG
I rotated the laser in the eye piece to see if something in the focuser was not sitting flush. The dot did not move as i rotated. So i don't think it is something not sitting flush.
This is giving me significant problems with my images - about 1/3 of the image is out of focus and i get elongated stars.
This is what i am getting tonight, after confirming everything is sitting properly:
http://core-au.net/astro/camera/1100d/new/1.jpg
It's horrible.
A few things i have tried:
- With and without a field flattener. The image above is without a flattener. The problem still exists, but it slightly reduced with a field flattener.
- Different camera. I tried a Canon 7d in case the problem is my camera, but it gets the same thing.
- Rotated the camera. The bad area of the image rotates as i rotate the camera, further confirming that it is not the camera.
Any suggestions or things i have not tried?
Cheers.