Quote:
Originally Posted by Eric Hahl
I tried something new for me. I set the camera to Bin 2 which actually reduces the picture size but increases the saturation.
|
You're doing single shot color imaging, right? I can't remember...
For those that weren't imaging back then, some history...
Back in the day (circa 2001) we only had monochrome CCD cameras. To get color images, we had to shoot through several filters and combine the images as color channels in something like Photoshop. Originally, we would shot R, G and B channels and combine them, with each filter requiring different total exposures based on the sensitivity of the camera. Oh...EVERYTHING had to be done without changing any equipment (focus, camera presentation, polar alignment, anything) because we couldn't plate solve back then...
Back to the history lesson. Around 2001 we started playing with L-RGB imaging, which was basically taking the best hi-resolution monochrome image you could put together, and then "tinting" it with lower resolution RGB components. We would regularly shoot the RGB images at 2x2 or 3x3 binning to increase sensitivity, but also because the files were much smaller, since we couldn't store enough images on a computer to do full resolution L-RGB at once! Ha! Not only was it hard to store the actual images, but processing so many channels at once would melt RAM!
So, you'd take the L channel (luminance, which was mono) at 1x1, longest exposure you could handle. Tint it with some 2x2 or 3x3 RGB data, which was much shorter. End up with a "true color" image which looked better than the older RGB only stuff anyways.
I once did a 3x3 mosaic of Andromeda, L-RGB, 3 degrees across total. 4 channels, darks, flats, biases...turned out to be something like (10+10+10)+(10)+(9+6+4) images per spot, for dark/flat/bias/L/B/G/R data, at 1Kx1K camera resolution, 8 bits per pixel. So, about 60 shots times 9 locations. I could only process I think 3 images at a time because of memory limits on my laptop. 3 flats together, save master subflat #1 for the first spot. 3 more merged, master subflat #2. Etc. Then, merge the subflats for each spot to a master flat for that spot. Rinse and repeat for everything else. took me MONTHS to put it all together.
Now Eric can get that same image with his Redcat in 15 minutes of imaging and an hour of processing.