Capture Flat Histogram Adjustment
Capture Flat Histogram Adjustment
When using the Capture Flat command to create flat frames for use with OSC data, is it necessary/helpful to align the RGB channel peaks displayed in the histogram?
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Re: Capture Flat Histogram Adjustment
Hi,
not really. There are two ways you can capture a flat for a colour camera...
1) As a RAW colour flat - this will work to remove dust shadows and dark corners, but will also tend to perform white balance correction automatically (providing you illuminate with white light). On the down side, due to the relative sensitivities of the different colour channels, this can be hard to set up correctly (often hard to get blue bright enough without having too much green)
2) As a monochrome flat - in this case SharpCap turns the RAW frames to colour, then to monochrome and makes the flat from those. This will still correct nicely for dust shadows and dark corners, but will not affect the colour.
I usually recommend option 2, in which case messing with the colour balance really has no effect. To be honest, I would usually suggest leaving the colour balance adjustments at their default values (50/50 for ZWO cameras for instance) - don't worry about colour cast until you are processing the images.
cheers,
Robin
not really. There are two ways you can capture a flat for a colour camera...
1) As a RAW colour flat - this will work to remove dust shadows and dark corners, but will also tend to perform white balance correction automatically (providing you illuminate with white light). On the down side, due to the relative sensitivities of the different colour channels, this can be hard to set up correctly (often hard to get blue bright enough without having too much green)
2) As a monochrome flat - in this case SharpCap turns the RAW frames to colour, then to monochrome and makes the flat from those. This will still correct nicely for dust shadows and dark corners, but will not affect the colour.
I usually recommend option 2, in which case messing with the colour balance really has no effect. To be honest, I would usually suggest leaving the colour balance adjustments at their default values (50/50 for ZWO cameras for instance) - don't worry about colour cast until you are processing the images.
cheers,
Robin
Re: Capture Flat Histogram Adjustment
Thanks very much Robin!