White ballance on pi amera


When I do the full calibration or the auto white balance the best I can get is slightly green.
Image below with true white added for reference.

As I have no experience with this type of things, is one supposed to get a true 255,255,255 white after the calibrations? If yes, what can I do to improve it?

Thank you for your help

You would not expect 255,255,255 as that is saturated white and leaves no room for variation in the image. The sample will generally make the image darker, so after calibration you would expect it to be a neutral colour and quite bright, but not near 255 on each channel.

Your example does look to be uniform and a reasonably neutral colour. On my screen it seems more a beige tint than green. Which version of the server are you using? The version number is recorded in the about tab. If you are not already on v2.10.0b1 and are happy to use a beta release, then instructions for installing v2.10.0b1 are here. The usual beta release caveats apply, but it has been out for a while and appears to be stable. It includes a much improved auto calibration routine for the camera.

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I understand, thank you.
I am using the beta release.
Thanks a lot for the clarification.

The setpoint is a raw reading of about 700 on each channel - this is converted to an 8 bit value in processing, and I think with a digital gain of 1 it should correspond to ((700 + 64)/1024)*256 ~ 190. We could probably increase that a little - but once I hit the point where it worked reliably, I did’t have time to optimise much further! What I’ve not done is figure out whether that does correspond to a “white” point of 190, or whether there are nonlinearities in the image pipeline that mean it’s more than that.

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