Why does Pollux look purple

[AlistairW]

Hello,

Quick and dirty 30 second sub of Pollux. I have a Bader BCF modified camera and a CLS CCD clip filter in. It's out of focus as I was just investigating something else. Is purple ok ?

Thanks

Alistair

Edited February 15, 2016 by AlistairW

[JR1987]

silly question.. but have you calibrated you RGB?

[AlistairW]

Hi,

Not sure what you mean by calibrating RGB ?

Hmm - maybe it's something else though. I was using backyard EOS and performing a 10s Preview to produce this "jpg". When a camera produces a jpg does it use the custom white balance ? - Should I be looking at the RAW file which will 'not' have the custom white balance applied. Or do I have this wrong ? - (No processing or stacking has happened).

The only reason I thought it looked strange is that my scope is an apochromatic and should not be effected by purple fringing as the light is correctly focued. Purple fringing is more usually assocaited with acromats I believe.

Thanks

Alistair.

[Uranium235]

The purple is caused by the colour balance of your camera, try shooting a custom white balance pic and save it to your memory card. Best way to do that is on a sunny day, take a photo of a sheet of white copier paper (so it fills the frame), then set that as your custom white balance. The clip filter also shifts your colour balance slightly, so you may need to tweak it a little in processing. But try the custom white balance first.

[AlistairW]

Thanks Uranium, that makes sense. I had a look at the white balance setting last night and it was set to tungsten, which I think further adds to this colour. I usually use RAW, but jpg has threw me for a while. When I get a chance I will take a look at the RAW image.