Tuesday, May 2, 2017

The Pinwheel Galaxy April 23, 2017

These images of the Pinwheel in Ursa Major were taken as a test of the DS16C imager in hazy skies with consequent moderate light pollution. I took some suboptimal darks (I made the mistake of taking them at the same exposure setting as the camera was set to for imaging, whereas the current recommendation is to take darks at 2x exposure). The result is significant color noise that produces a diagonal "sleet" on the image as a result of stacking. I turned down saturation (about 90 x 60s frames were stacked here) and that helped a little. I'm going to take some more exposures as soon as we get clear skies and experiment on getting images as noise free as possible while exploiting the imager's gain control to keep exposures as short as possible. This a cropped image taken with the 8 inch f/4 newt.