Quote:
Originally Posted by Shiraz
Hi Suavi
Calibration was a standard dark subtraction and flat compensation - read noise remained as is ( actually I would love to find a way to subtract the read noise  ). I guess I could have rescaled the raw 12 bit data by padding out with zeros, but didn't see the point - stacking the 12 bit data showed what happened.
Sorry, but I don't understand why you suggest 7-10 bits - the 694 and the 1600 both have over 11 bits dynamic range. All I have done is chop off the bottom 4 bits from some 694 data - to show that it isn't necessary to digitise to 16 bits with an 11 bit DR CCD. |
Fair enough - my bad with subtracting read noise
I had subtracting master bias in mind, and that would normally add more noise anyway...
The part I do not understand though, is why 1600 has over 11 bits of dynamic range available per sub. Is the read noise really as low as less than 1 bit per sub? Why then these chips saturate so quickly, while a CCD with even smaller pixels and with a greater read noise takes significantly longer to saturate pixels? Sorry for being so thick and thus slow to understand...apparently there are no silly questions, but I somehow feel that way right now...LOL