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Old 30-05-2016, 10:07 PM
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Shiraz (Ray)
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Join Date: Apr 2010
Location: ardrossan south australia
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been doing some bias and dark runs. of course it's cloudy.

at high gain, this thing has almost no dark current and a vanishingly small amount of read noise - I have not found any pixels that are stuck on and even the few hot ones are really only warm. There is a little bit of large scale variation in what dark levels there are - looks a bit like wafer cutting/polishing marks maybe. However, the overall dark levels are low enough that I think dark cal can be dispensed with if dither is used.

There is a small amount of very low level impulse noise at high gain - it will be easy to process out and is of no consequence, but more intriguing is what it might be. Some of the noise locations can persist across a couple of frames, suggesting that it might be local ionising radiation dumping charge in some parts of the chip circuitry. Before anyone races out to say that the chip is noisy, please note that the exact opposite is actually the case. The level of the noise impulses is typically only a few electrons and in any other chip, they would be almost entirely hidden by read noise (eg the effect would not be visible in my H694). It is only because the 1600 is so eerily devoid of noise that this minor effect (whatever it is) can even be seen - that really appeals to the inner nerd.

Last edited by Shiraz; 30-05-2016 at 10:48 PM.
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