DSLR - background field colour cast...


My brightfield images always have a pale "salmon coloured" cast to the
background. I generally run the lamp at around 6-7V, but the issue
persists at 12V too - so I don't think it can be a colour temperature
thing(?). Visually, the background looks perfectly white to me.

I'm projecting the image directly onto the 10D's CMOS sensor and
thought maybe IR was the problem but adding an IR blocking filter just
before the condenser made no difference!?

Is this just a common issue that's always fixed by later colour and
white balance tweaks (which seem to work just fine), or am I missing
something at the capture stage?

Cheers
Beats

PS. Scope is a Zeiss ICM 405 inverted with an EOS 10D attached to the
front photoport. Light is 12V/100W halogen.

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