If the sensor is of the "old" style, there will probably not be a problem.
These would be made of material like the old selenium cells from the Weston
meter days, or even the somewhat newer cadmium sulfide/selenide materials.
These have responses that peak in the visible and taper off equally to the long
(IR) and short (UV) wavelengths. The cadmium selenide mixtures have more red
response and work well for tungsten light door entry annunciators.
The newer silicon diode sensors are a real pain, as the intrinsic response of
the silicon is very high in the IR region, and most filters are qualified by
their spectral response in the visible and can transmit almost fully in the IR.
I built my own enlarger easel densitometer and originally used a silicon
photodiode due to its many decade linearity and wonderful sensitivity, but found
that the IR transmission of silver in film was too high. I'm now using a
cadmium sulfide photoresistor with good results. It's not quite so linear but
adequate.
Paul Simon 70760.1511@compuserve.som