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Old 16-10-2020, 08:48 AM
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multiweb (Marc)
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Join Date: Oct 2007
Location: Hinchinbrook
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Quote:
Originally Posted by Tulloch View Post
If you don't use an IR cut filter, then the RGB channels will be swamped with IR and the planet's colours will be incorrect. Here is some more information on that (written for the ASI224MC, but also applicable for the 462 as the IR sensitivity is even higher). The 462 has an IR transparent window, so you need to get an IR cut filter for colour imaging (I just bought the ZWO IR cut filter when I bought the camera).
https://www.planetary-astronomy-and-...lter-asi224mc/

The 462 sensor is more sensitive than the next best sensor (the 224MC which I have), it has a lower noise level (0.5e vs 0.8e) and the smaller pixels mean that its best focal ratio is f/15 rather than f/20.

The maths which shows how the focal ratio = 5x the pixel size of the camera is determined is attached. Don't worry about the Bintel sampling tool, as mentioned above it's designed for DSOs not planetary.

Andrew
Cool. Some more reading to do. I have various IR cut filters. Will fit one in the light path next session. You've mentioned the ideal focal ratio before. Will check that out too. To date I have gone as long as the optics and mount allow me which is ~8m @ 200mm aperture.
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