Leaderboard

Thanks again for this!!!!.......I will try to reprocess using these tips...............it's been super crappy here lately in DE, either cloudy/rainy or windy. I was hoping to get out before the end of the month and try to snap a photograph of the comet, I read an article that says it's visible low in the Eastern sky before sunrise, perfect for Bethany beach, we'll see how it goes.

Part Two After stacking, you may find although the light gradient is diminished, there is still a gradient or two or more in your image. As you are tracking the sky object throughout the night, gradient sources can change, sources may wander in and out of your region of interest or your lens' field of view. After stacking, you can try extracting the background, again using a degree one polynomial or a higher degree polynomial to diminish more complicated gradient patterns. You may have to split the sequence into parts and work on the diminishing the gradient in the parts, putting the sequence back together and then move onto registering and stacking things. Gradients are ... hmm, not nice. (Oh yes, you can get them from bright stars as well, Alnitak is very famous and gives its regards.) But there is a tool you can try before resorting to such measures. Right after stacking, with the view mode in AutoStretch: Open up the Image Processing menu and select Background Extraction... but this time choose the RBF method: Change the View Mode to Histogram and just as in Part One, place some dots where the background should be 'dark". Once you think you have enough dots (a few still goes a long way) click on the Compute Background and take a look: If the image looks okay, click on the Apply button, close the BG extraction window and you are ready to continue on with your regularly scheduled editing and processing. There are plenty of tutorials out there more thoroughly discussing finer points of using these tools, but those are waaaaaay beyond this jumpstart guide, hopefully this is enough to be able to get you going 😀. This is the end of Part Two. Uh, some notes: Save your work and save often! Stuff Happens, Murphy was an optimist. Also, you may have observed there a lot of large-sized intermediate files with the .fit extension littering your folders. The only one you really need, after the project is finished, is the stacked image, its file name should end something like ... _stacked.fit, the other files are intermediate development files and you can toss them. You may want to keep the .raf files in case you want to go back later and try something different.