2018-05-15, 02:59 AM
Greg:
I've been trying out the exposure calculator in ST3 Pro, for my typical rig which is an 8" SC @ .68, with an ASI294 camera. I'm getting counter intuitive results, based on my experience with the camera. I'm pretty new to all of this, so I suspect I'm prone to newbie goofs.
I entered the data from here https://astronomy-imaging-camera.com/pro...pro-color/, using the relative response in bgr to simulate QE. I typically operate at gain = 350 and T= 0 degrees C, and used the data from the charts for read noise, dark current and gain. Read noise =1.2, Gain at 0.2 e/adu, and dark current .07 e/sec. See below
I always use a LP filter - and Astronomik CLS (non CCD) but don't know how to deal with that in the setup. Bortle 6 skies.
I'm not trying to do traditional AP, but rather electronically assisted observing. I'll often post process the camera's raw frame. Good enough for me.
I can get decent images on the screen - see my capture of ngc 6503 here https://www.cloudynights.com/topic/14451...try8568040, post number 6679.
But when I use the input, ST3 says that I can't get SNR of 3 (marginally detectable) unless I'm at 22 minutes of 8 second exposures, which is twice as long and far less quality than the screen shot.
Besides the LP filter issue, I don't know how to use ST3 to deal with the stretching I obviously can do within the capture software.
Are there any tips you can give me for enahncing my use of ST3 as an imaging/observing tool, or are my expectations too high ?
Thanks for the great product.
john
I've been trying out the exposure calculator in ST3 Pro, for my typical rig which is an 8" SC @ .68, with an ASI294 camera. I'm getting counter intuitive results, based on my experience with the camera. I'm pretty new to all of this, so I suspect I'm prone to newbie goofs.
I entered the data from here https://astronomy-imaging-camera.com/pro...pro-color/, using the relative response in bgr to simulate QE. I typically operate at gain = 350 and T= 0 degrees C, and used the data from the charts for read noise, dark current and gain. Read noise =1.2, Gain at 0.2 e/adu, and dark current .07 e/sec. See below
I always use a LP filter - and Astronomik CLS (non CCD) but don't know how to deal with that in the setup. Bortle 6 skies.
I'm not trying to do traditional AP, but rather electronically assisted observing. I'll often post process the camera's raw frame. Good enough for me.
I can get decent images on the screen - see my capture of ngc 6503 here https://www.cloudynights.com/topic/14451...try8568040, post number 6679.
But when I use the input, ST3 says that I can't get SNR of 3 (marginally detectable) unless I'm at 22 minutes of 8 second exposures, which is twice as long and far less quality than the screen shot.
Besides the LP filter issue, I don't know how to use ST3 to deal with the stretching I obviously can do within the capture software.
Are there any tips you can give me for enahncing my use of ST3 as an imaging/observing tool, or are my expectations too high ?
Thanks for the great product.
john