15th Feb 2024: Astro Pixel Processor 2.0.0-beta29 released - macOS native File Chooser, macOS CMD-Q fixed, read-only Fits on network fixed and other bug fixes
7th December 2023: added payment option Alipay to purchase Astro Pixel Processor from China, Hong Kong, Macau, Taiwan, Korea, Japan and other countries where Alipay is used.
I am using the trial version of APP to compare/contrast to using Siril. I have lights, darks, flats and bias frames all captured under clear skies this past weekend.
I made one pass through trying each feature on my own and experimenting with options. I was disappointed to find the resulting integrated image had a lot of color noise, something I have not been getting with Siril.
After reviewing this tutorial, I tried to tip at the end, letting APP do everything automatically. I still got the same kind of color noise. See screen shot below.
Surely this is user error but I haven't seen anything in the various tutorials that would explain what I am doing wrong.
Suggestions?
That looks a lot like you didn't dither while taking the data, is that correct? Dithering will remove the streaky kind of noise you show here. Are you stretching similarly if you compare the results? I would assume it should look similar in Siril if no noise reduction was added.
No, no dithering as I am using Star Adventurer 2 without guiding. Guess I should have also mentioned what I am shooting with: Evostar 72ED, 0.85 focal reducer, Nikon D750 (unmodified). Doing some searches on dithering, it seems like the noise I am seeing out of APP is not uncommon without dithering. Appears that Siril is doing something that avoids the noise, just not sure what.
I don't know, that may be, but the noise pattern is so called "walking noise", which requires dithering. Can you show the integrations side by side?
