Contains: Other
The problem with the light and the focuser, 




    

        Michael

The problem with the light and the focuser

Description

I have a serious problem with the crayford focuser and light injection. Picture A) shows the problem: This is a stacked picture of 80 frames with 120 secs each. The background shouldnt be so light. I have tracked the problem down. In picture D) you can see where the light enters the system.

The problem is very massive. If i put the system out by cloudy daylight (no sun exposure) and expose 1 sec with gain 256 the picture is nearly pure white (same with 15 secs and gain 0 -> see picture C for an example). Really a lot of light enters the focuser. If i put a dark cloth over the focuser the picture is black. I verified the light-entry-points with a flashlight.

I need some sort of cover for the end part of the focuser. I will track the steps i take to a solution here. Maybe this helps if someone suffers from a similar problem.

In E) you can see the first approach to a solution: My lovely wife made me some sort of a... ehm... condom. It is way better than before, but not perfect. I think some sort of bag will do the job.

F) is an image under nearly the same conditions like C). Daylight, clear sky, no direct sun exposure. Way better!

Comments

Author

khrrugh
Michael
License: None (All rights reserved)
2400
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Revisions

  • The problem with the light and the focuser, 




    

        Michael
    Original
  • The problem with the light and the focuser, 




    

        Michael
    C
  • Final
    The problem with the light and the focuser, 




    

        Michael
    D
  • The problem with the light and the focuser, 




    

        Michael
    E
  • The problem with the light and the focuser, 




    

        Michael
    F

C

Single shot, 15 secs, gain 0.

D

The part where the light enters the system.

E

Version 1.0: The Condom.

F

Single shot with condom, 15secs, gain 0.

Histogram

The problem with the light and the focuser, 




    

        Michael