astrorunner
Member
Hi everyone, this is my first post here.
I'm relatively new to AP, started in January. I have been trying to learn PI for about 2 months now and I've reviewed a couple of online videos from Harry's Astroshed and I've been slowly working my way through Warren Keller's book "Inside Pixinsight". My goals were to use PI as a "one stop shop" for basically all of my processing needs, as I don't know Photoshop and I'm a bit reluctant to purchase it (just yet anyway).
I'm using a Canon T3i DSLR with a Celestron 9.25" XLT OTA and currently non-guided. I will soon upgrade to a guided system but I was hoping to master at least a basic "workflow" to get reasonable pictures to look at before upping the complexity.
My main question now involves using the BatchPreprocessing script to calibrate and stack ("integrate"). I've shot with darks and flats and various ISOs, and with 30 second exposures for my light subs (I can't really go much longer unguided). I also made master bias files for various ISOs out of sets of 600 exposures taken at the max shutter speed (and in the refrigerator, to simulate the normally cool or cold outdoor conditions I shoot in). From what I can tell, the calibration appears to go well. I get master darks that are uniform gray in color when I bring them up an apply the auto STF to them (using the radioactive-symbol button), and I can see a few hot pixels sprinkled around. My flats are also gray but you can see the dust motes and vignetting at the corners. The master bias also appears to be mainly uniformly gray with perhaps a few vertical line patterns barely visible.
The issue comes with the final product of all this. The output "master light" (I think that's what you'd call it) from the script is very very green and often grainy and noisy. I guess a lot of the noise could just be light pollution from the city I'm shooting from. The green though is bright and everywhere. I can use the "SCNR" program to remove it. But should that green be showing up at all? Is something missing or wrong with a setting that will cause this green to appear like it does?
For comparison, I also have run Deep Sky Stacker with the same dataset, and I also get green objects, but not quite as pervasive as with PI.
Also, and this is a problem I've encountered with DSS as well as PI, my stars seem to have virtually all color stripped from them, everything just looks black and white (at least after I run SCNR, and green is gone!). Is this just a matter of my needing to run additional stretching of some sort to enhance colors, or again is there a setting somewhere that is doing this? I have not yet learned or mastered any of the processing techniques beyond just calibrating and stacking (I've played with the histogram tool a bit but that's about it; in Gimp I've used "curves" and "levels").
Finally, the "Inside PixInsight" text walks me through the individual processes that make up the BatchPreprocessing procedure. However, when I try to calibrate using this approach, my master darks and master bias come out looking blue or green (after applying an STF to it). This doesn't seem right. I don't get this result when running the BatchPreprocessing. A friend of mine who has been doing AP for many years almost never uses anything beyond the BatchPreprocessing script, although PI strongly recommends you to run ImageIntegration for light frames as a separate step, for better quality.
Sorry if this is a lot on the table but I'm really looking for some basic guidance here. I'm not necessarily needing to master the most advanced features of PI right now, I just want a basic workflow that will work with my DSLR for now.
Thanks!
I'm relatively new to AP, started in January. I have been trying to learn PI for about 2 months now and I've reviewed a couple of online videos from Harry's Astroshed and I've been slowly working my way through Warren Keller's book "Inside Pixinsight". My goals were to use PI as a "one stop shop" for basically all of my processing needs, as I don't know Photoshop and I'm a bit reluctant to purchase it (just yet anyway).
I'm using a Canon T3i DSLR with a Celestron 9.25" XLT OTA and currently non-guided. I will soon upgrade to a guided system but I was hoping to master at least a basic "workflow" to get reasonable pictures to look at before upping the complexity.
My main question now involves using the BatchPreprocessing script to calibrate and stack ("integrate"). I've shot with darks and flats and various ISOs, and with 30 second exposures for my light subs (I can't really go much longer unguided). I also made master bias files for various ISOs out of sets of 600 exposures taken at the max shutter speed (and in the refrigerator, to simulate the normally cool or cold outdoor conditions I shoot in). From what I can tell, the calibration appears to go well. I get master darks that are uniform gray in color when I bring them up an apply the auto STF to them (using the radioactive-symbol button), and I can see a few hot pixels sprinkled around. My flats are also gray but you can see the dust motes and vignetting at the corners. The master bias also appears to be mainly uniformly gray with perhaps a few vertical line patterns barely visible.
The issue comes with the final product of all this. The output "master light" (I think that's what you'd call it) from the script is very very green and often grainy and noisy. I guess a lot of the noise could just be light pollution from the city I'm shooting from. The green though is bright and everywhere. I can use the "SCNR" program to remove it. But should that green be showing up at all? Is something missing or wrong with a setting that will cause this green to appear like it does?
For comparison, I also have run Deep Sky Stacker with the same dataset, and I also get green objects, but not quite as pervasive as with PI.
Also, and this is a problem I've encountered with DSS as well as PI, my stars seem to have virtually all color stripped from them, everything just looks black and white (at least after I run SCNR, and green is gone!). Is this just a matter of my needing to run additional stretching of some sort to enhance colors, or again is there a setting somewhere that is doing this? I have not yet learned or mastered any of the processing techniques beyond just calibrating and stacking (I've played with the histogram tool a bit but that's about it; in Gimp I've used "curves" and "levels").
Finally, the "Inside PixInsight" text walks me through the individual processes that make up the BatchPreprocessing procedure. However, when I try to calibrate using this approach, my master darks and master bias come out looking blue or green (after applying an STF to it). This doesn't seem right. I don't get this result when running the BatchPreprocessing. A friend of mine who has been doing AP for many years almost never uses anything beyond the BatchPreprocessing script, although PI strongly recommends you to run ImageIntegration for light frames as a separate step, for better quality.
Sorry if this is a lot on the table but I'm really looking for some basic guidance here. I'm not necessarily needing to master the most advanced features of PI right now, I just want a basic workflow that will work with my DSLR for now.
Thanks!