Back at it...a couple great dark nights are upon us! Here we have another in the Messier marathon series, M30, a globular cluster in the constellation Capricornus. This will be the last photo taken at 12,800 ISO setting for a while. Even though much has been removed from the shot, the noise is a bit excessive. Taking this last super high gain shot also allowed me to test my flat I created.
Worked great. Vignetting go bye-bye.
This unguided photo taken with the Canon T1i as 104 x 15 second JPEG frames, long exposure and high ISO noise reduction enabled, and calibrated with 200 bias, 100 dark, and 200 flat subs.
Below is my exciting new flat used in the calibrating the photo above. Created it by placing the telescope under the patio in this bright Arizona afternoon sun and taping a white sheet of paper across the telescope opening. Made sure the sunlight was indirect and bright across the entire surface of the paper. Set the Canon into AV exposure mode and ISO 100, proceeded to collect 200 frames!
After calibrating with bias, the frames were stacked together creating this master flat. The histogram in the camera showed it nailed dead center and the red, green, and blue curves aligned right on top of each other. Don't think I could get it any closer to grey than that!
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