When you are setting up for the first time, you can create master calibration files.
I went to Capture and ran darks fine.
Then I went to flats and it had a place for bias.
Why isnt there an option to create the bias first?
You cant create the bias while the light is on the flat panel.
How does this work?
thanks
capture menu
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Re: capture menu
Hi,
it's not really a traditional bias frame (the sort that you use if your dark frames are a different exposure to your light frames). It's a minimum exposure flat frame, which is usually a very good approximation for a bias frame.
The thing is about capturing flats is that there is no strict requirement for a true bias frame - you can make a perfect flat by taking flat frames at (say) 500ms exposure and also at a much lower exposure (say 1ms). Subtract the dark 1ms frames from the brigher 500ms and the result is a perfectly calculated flat frame with the effect of the 'bias offset' of the camera removed. It's a good way to create flat frames with the minimum hassle, you only really need to use proper dark flats if your flat exposure length is substantial (more than a couple of seconds).
cheers,
Robin
it's not really a traditional bias frame (the sort that you use if your dark frames are a different exposure to your light frames). It's a minimum exposure flat frame, which is usually a very good approximation for a bias frame.
The thing is about capturing flats is that there is no strict requirement for a true bias frame - you can make a perfect flat by taking flat frames at (say) 500ms exposure and also at a much lower exposure (say 1ms). Subtract the dark 1ms frames from the brigher 500ms and the result is a perfectly calculated flat frame with the effect of the 'bias offset' of the camera removed. It's a good way to create flat frames with the minimum hassle, you only really need to use proper dark flats if your flat exposure length is substantial (more than a couple of seconds).
cheers,
Robin