[rcheshire (Rowland)]

This is a combination of iso1600 and iso800 frames, 40 in all, approx 2 hours - different apertures, f5.7 and f6.3. I played around with these over 2 nights

No dark frame calibration - bias and flat only. I did several test runs and frankly, the difference was negligible. Hot and cold pixel rejection was no problem even without the darks. I think the result is better - not sure what's going on with the darks?

The first post processing task was to resample the image for display, which reduced noise levels considerably and then process, instead of the other way round. The full size image is saved, so nothing lost.

I will revert back to an aperture ring to get rid of the spikes in future.

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