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Old 10-06-2016, 12:45 PM
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Shiraz (Ray)
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Join Date: Apr 2010
Location: ardrossan south australia
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yep, that is an excellent result for the time taken.

looks like we will need to use darks for NB - your image shows some marks that I take to be wafer polishing marks - upper right. I get similar marks in my darks and assume that the silicon characteristics vary slightly and the dark current is different where these marks appear. I don't think there is anything similar in my bias results (haven't checked at long exposure yet). On that basis, maybe try subtracting bias from your darks and then subtract the remaining dark signal from your lights - that will leave enough of bias pedestal to protect your data and the bias noise seems to be pretty low, so will stack out with dither. Ultimately a full bias/dark calibration will be best, but if DSS won't do it properly, this may be a viable approach for now.

broadband signal is high enough that none of these effects are visible.
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