UVEX Collimation
Posted: Mon Dec 02, 2019 4:28 am
I had difficulty collimating my UVEX, but left it for a while because I have been busy collecting data with the Alpy. But now there is a run of bad weather I'm back to trying to sort the UVEX again, in anticipation of decent weather in a week or so. Hopefully.
The problem is that I get a nice spectrum on one side of the slit, but it degrades as it goes to the other side. It's not a camera focus alignment issue (I rotated the camera 180 degrees and found that the image was consistent, nor does it improve as you move past focus). It's not a slit issue (I reinserted the slit rotated 180 degrees, but the image orientation stayed consistent, with the widening at the top).
I have removed and reinstalled both mirrors, which appear to be sitting nicely in their mounts, with the mounts well seated in the printed holders, which in turn are nice and flush against the inside of the case. The grating holder is also flush against the inside of the case, so hopefully everything is nicely lined up in the same plane. Tweaking mirror position doesn't seem to help.
I removed and reinstalled the cylindrical lens.
So I'm not quite sure what is causing the problem. Any ideas very welcome!
The problem is that I get a nice spectrum on one side of the slit, but it degrades as it goes to the other side. It's not a camera focus alignment issue (I rotated the camera 180 degrees and found that the image was consistent, nor does it improve as you move past focus). It's not a slit issue (I reinserted the slit rotated 180 degrees, but the image orientation stayed consistent, with the widening at the top).
I have removed and reinstalled both mirrors, which appear to be sitting nicely in their mounts, with the mounts well seated in the printed holders, which in turn are nice and flush against the inside of the case. The grating holder is also flush against the inside of the case, so hopefully everything is nicely lined up in the same plane. Tweaking mirror position doesn't seem to help.
I removed and reinstalled the cylindrical lens.
So I'm not quite sure what is causing the problem. Any ideas very welcome!