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Hello,
Firstly, thanks to all for helping me out with these issues! As I have said earlier I am extremely new to all of this. I've done a bit of planetary photography, but never tried this aspect of the hobby. Thus, it is the first time I'm using any sort of mount with these abilities, and I never have used a CCD Camera before. Clearly, I am at times overwhelmed by the large number of factors to juggle!
A few things are becoming clear however, and ambiguities in the PMX/T-Point manuals don't help.
1. My Polar Alignment is probably way more inaccurate than indicated. I think I possibly have a highly polluted model because I collected points all over the sky instead of restricting myself to a more confined area and developing a refined PA. The manual says to get the first 6 points in a confined area and then to get additional points from a larger area of the sky. To me that is fairly ambiguous and I basically accepted points quite far away, and probably too low. I think that, + camera flexture, has led to erroneous data. Also, my pier is not entirely level. SB says this doesn't matter, but I think it might to some extent in that it just adds a further correction factor. I intend to level the pier and start over.
2. I had a brief window to experiment with some very short photos on Friday night. I also have downloaded a trial copy of CCDInspector. The photos are unguided (I have yet to even try this yet!) and 10 seconds in duration. I took two photos with the camera rotated 180 degrees for the 2nd. I don't see the degree of distrortion in the previous photos I posted at the top of this thread, but I would appreciate some input re the curve maps that I am attaching. I took the images before reading about acceptable single frame images, but I hope something useful might be seen anyway. The images are unprocessed, no darks, just stretched in CS5. Binning was 1x1 but I reduced the image size by 50% to post here.
I think the fall off in sharpness is possibly the result of using no field flattener and the KAF8300 chip is slightly larger than the acceptable flat field of view from the TEC140. There is also the possibility that the inbuilt filter wheel (with 31mm filters) in the Moravian G2-8300 camera is vignetting the field slightly though Pavel Cagas (of Moravian) says this isn't the case. Anyway, what I am most concerned about is whether what CCDInspector is reporting is a minor or serious problem. Any and all help is greatly appreciated!!
Peter
PS I have another question about binning. Should binning cause the object being imaged to shift in the field of view and reduce the field of view? From what I've read, I don't think so but stand to be corrected. I'm also attaching 2 additional images captured by the camera plugin in TSX.
photo 5: binning 2x2
photo 6: binning 3x3
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