2022-05-29: APP 2.0.0-beta2 has been released !
Download links per platform:
Who can help me postprocessing Needle galaxy
who can help me postprocessing my needle galaxy data? I stacked the whole thing just using darks (flats and bias seem to be less beneficial for me with the ASI294MC pro). Now I can't get a solid background using the tools in APP and when I export it to Photoshop the data gets even worse (16bit tiff). I watched several tutorials on post processing in PS but I haven't found a good workflow for me yet. Also I have no comparison with my own data of what is possible with this data. It is getting quite frustrating regarding post processing and takes some fun away at the moment.
If you do want to try, please let me know the workflow and settings so I can learn from it. The fits file straight after the stack in APP is attached via a dropboxlink (67x 30s, 50x 120s, 30x 300s, 10x 600s, all gain 120 and -10C).
Thanks for the help.
I don't know if this is what you were hoping for in the way of advice/assistance - and my processing tastes may well be different to yours - but this is what I achieved with your data using solely APP.
My steps were:
1. Batch Modify, to crop the image
2. Remove Light Pollution
3. Calibrate Star Colours
4. HSL Selective Colour - to remove any green pixels and remove chromatic noise from the background.
At this point I normally use APP to create a 16 bit TIFF which I import to Photoshop Abobe Camera Raw for Noise Reduction and sharpening.
If I was working with your data I would definitely have used flats to eliminate the vignetting that is very evident in your drop-box file, and have used Crop during Integrate. However the end result seems to me pretty decent.
PS: And after some minor titivation in Photoshop Camera Raw:
Thanks Mike, very nice. Yes, flats will help you greatly to improve on overall quality, the downside of them is that they are the most "difficult" calibration frames to make, you need to take good care of all the factors that influence good flat frames.
looks good! Sorry for the late reply. I was caught in daily business. Looks great! I guess I need to get more out of APP. I never use the HSL because for me it is so not intuitive compared to Photoshop.
I didn’t know that flats also work against vignetting. I have a hard time making good flats with my newtonian. Together with darkflats I usually destroy my ‘good’ data and induce more noise.... I’ll start working on my HSL knowledge and retrying to make good flats (als my autofocusser is in the way to put my flatpanel flat on the telescope).
Thanks again for your efforts and at least I see what is possible and what to work on for me!
I fully agree with you that taking flats is a pain, even thought I use a refractor and have a flat panel. I'm lucky that I keep my rig indoors and fully assembled so I only take new flats if I notice a significant new dust bunny or manually rotate the camera for framing purposes. The big hassle for me is adding / removing sheets of paper to change brightness for different filters.
I tend to use HSL only for killing chromatic noise and dealing with any green casts as covered in Part 6 of Mabula's Mosaic Tutorial video. If I need to do anything more dramatic I use PS.
Finally I must say I was very impressed with the little work that was need in CSC with your data. I have a CCD mono CCD camera but am increasingly tempted by a CMOS OSC.
i’m saving money at the moment to buy a refractor. That will make life so much easier (no collimation, easier setup, smaller, lighter) I can leave my image train assembled as well. But I just started recently with paying attention to framing the same subject the same way.... So maybe I should take an afternoon to build some nice flats.
thanks! I’ll take a look at the tutorial you mentioned. Never watched the mosaic tut , but i guess it it worth it!