G13 has been designed for people to get their feet wet without all the complexity of understanding how to process images. The design goal of G13 is, simple, fun, one click image, delivered via email. This is a beginners to intermediate system not a system that someone yourself might find interesting long term. By design compromises exist on G13
Let me explain.
The image glow you are referring to is caused by the moon. We are evaluating the performance and may take it offline during the full moon.
The calibration process is automatic a bias scaled dark is applied and a flat.
The DDP is applied via a script and I try and set the points based on the histogram, however it doesn't always get it right but close enough for this system, clipping will exist nothing I can do about it in a automated system. This DDP doesn't sharpen the image.
Noise. This is a 10 min image 3:3:3 RGB shot at 1600x1200 on a 90mm refractor with a low QE CCD. To deal with the noise I reduce the image to 800x600 otherwise I would need to have exposure times of 30+ mins if not longer to keep the noise levels the same at full resolution. If I offered the 10 min full resolution image would be much less pleasing than the 800x600 image, because as you know reducing a image in size is a great way to deal with noise. Due to the signal to noise being so low when I JPEG compress the image it causes some graininess to it but no real more than in its raw format.
I then convert the image to a JPEG with a slight compression and delivery it via email. JPEG was choice as large portion of the users don't understand what a FITS or TIFF file is or how to correctly work with it, little alone click on the attachment and open it up in one click from the email. The ones that do they are more than welcome to trial whole GRAS network which includes access the the FITS files.
Overall the results have been really good and the feedback and been 95% positive.
Good to hear from you, hope things are going well for you.