Further to my last… the monitor is a Panasonic (same model no).
Problem is yellowy-brown whites i.e. not a clear white.
Downloaded the manual and tooled around in the service menu there may be a slight purity / convergence problem but I don’t have a test pattern generator at the moment (hoping to build one soon).
Have ya got a black and white camera ya can plug in and improvise a test card. Sounds like it may be an older unit with CRT showing its age.
Probable might need to readjust the RGB drives for a better b/w balance and this should follow thru when/if you plug a colour camera back in to it.
much easier to demonstrate then to (try) describe the proceedure.
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