Adding more data to the Elephant's Trunk Nebula

13 August 2021

Due to my new goto-capable mount it has become quite easy to take an image of roughly the same portion of space repeatedly for several nights. I knew that adding more data will result in an overall cleaner image but as it was hard to do for me to point to the exact same location I never even tried to combine data of several nights.

So naturally I was eager to see how an image of about 2h worth of data, which is about the maximum integration time of my previous images, will compare to one with double or more of integration time. The image shown above is the outcome of my efforts. For this picture I was able to more than double the integration time from 1h 46min or 53 subframes to 4h 56min or 148 subframes each with an exposure time of 2 minutes.

The image below is a comparison between the images with a shorter and longer exposure time. As I did process them slightly differently they look a little bit different. To show the benefits of adding more data I added a 100% cropped subsection in which the benefits of more integration time will be more apparent. The longer exposed one shows significantly less noise (color and luminance) than the shorter exposed image.