As a second test for my TEC-200, I decided to focus on the Hamburger galaxy. I'm not sure why I've always liked this target...certainly there are more interesting galaxy targets out there, I know. But whatever...I wanted to try an experiment. I shot 80 L frames with 10 minute exposures. I stacked 10, 20, 30, 40, ... 80 images and plotted the SNR ratio for each stack. My goal being to get some kind of handle on what kind of SNR I could expect and how many L frames I should be shooting as a rule of thumb. I fit a logarithmic function (I assumed a logarithmic relationship) to the data and plotted my results. Here they are:
The SNR is shown in db and the number of frames is across the bottom. This shows that I can quickly get into the high 40's, but to get into the 50's would take some real time, and to move into the 60's is likely out of reach for this target.
I'm not sure much the actual target impacts this curve, but it seems like it would have a great impact. Brighter targets, I would assume, would have more signal and, therefore, a better SNR. My inexperience is showing here, but perhaps some of you, my friends, with greater technical experience will chime in with some guidance.
In any event, here is the image that I ultimately produced. C and C always welcome.
Tim.
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