Rather than do a gazillion individual email replies, here are some short responses to each: ---------------

Patrick 2010-01-21 19:15 -700 Your comment about the tracking errors prompted me to look through images others have made using the 2-meter. Many have shorter exposures but some were longer. But all had round stars. Good to know its an anomaly for our SLAS imaging session.  Having to the "star-be-gone" thing to recover the images is pretty tediuous.

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Tyler Allred 2010-01-21 21:27 -700 I am curious about the cleaning process you are using. . . . In particular, I notice that the bright star at the top of the blue image is not seen in the green and red images. Also, the pulsar has been removed in some of the images, although the shockwaves are clearly seen. . . . How are you doing the cleaning... a filter?? No auto-filter - it was a 2 hour hand-job. I went through each image and where the stars were not round, I used a GIMP-Heal or GIMP-Clone tool to erase them.  For the three largest stars, sometimes that heal operation left a visually obvious artifact and the GIMP-Smudge tool had to be used to smudge the fix area. 

I was not consistent about removing the same stars in each layer.  The main point is that any larger round-stars are removed so the oval shape of any star (regardless of its size) is hidden when the final foregound transparent alpha layer just containing round stars is added back in. ---------------

Daniel Holmes 2010-01-21 19:39 -700   The only complaint that I would have about that night is there wasn't any explanation as to why we were doing the settings we were doing . . . My recollection is that we were still learning to use the telescope camera, since it was the club's first open session with the Faulkes. 300 seconds is a good ball park figure to get a feel what the exposure response curve of the camera was.  300 secs is a good starting point estimate.

As Tyler noted during the 1-15-2010 session, one of the drawbacks of Faukles setup is that you cannot get immediate access to the processed FITS images.  With a normal small scope setup you would take a 100 to 300 sec exposure, open the FITS file and check the exposure levels in a histogram of the image. If we had had that capability, we would have immediately been able from the first image to determine that the capture a-d-us (pixel values) were way too low and could have doubled the exposure times.  As it is, what the group collectively did was the right choice at the time but in retrospect did not work out.  I hope some of that can be fixed with some post-imaging processing. For me, this is a consistent problem that I've seen using commercial roboscopes at GRASS - no consistent online calculator or table of recommended starting exposures for each scope-camera-filter combination, so you are not burning up rationed or expensive online scope time. -------------- I also have one other general question for attendees at the session: Q1. What was the magnification used to make the images? I believe I heard it the images had an 8 x 8 arcmin TFOV.  Would that be about 390 power? ( 52 degs / (8 degs / 60 degs) ) Clear Skies, Kurt