Quote:
Originally Posted by gregbradley
What filters are they Terry?
I managed one image tonight and it seems as bright as it was last Friday. Very subjective measure but for what its worth.
Greg.
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Greg
I was meaning BVRI filters. Just a V filter which is a green filter is pretty useful. You take an image of the SN and surrounding stars that has a maximum value that is in the linear range of your CCD. For an antiblooming CCD that is usually about 50% of the max ADU of the camera.
Then using the known magnitude of one of the field stars you can measure the magnitude of the CCD. These mags can come from various sources.
Even using a green filter that you already have you can demonstrate the changing magnitude of the SN as long as you measure the same comparison star.