Hello everyone,

I have just gone back to Large Format after twenty years away. I am a commercial photographer with nearly thirty years worth of experience, but, I am at a loss with a project and would really appreciate your collective expertise.

I am currently trying to shoot on ektachrome 100 in the studio. The first polaroid came back with my calculated exposure for the lighting system - strobes with modeling lights as f13 @ 1/60 (I'm shooting on a Sinar F1 with a 210mm lens and behind the lens shutter) as being spot on, however, when the sheets returned from the lab they were massively underexposed with a deep orange cast - this I am familiar with in terms of a light/film error, so back to the studio...

This time I took incidence and reflection measurements with a flash meter and ran exposure tests on both settings. Again, a deep orange cast and underexposed... Back again to the studio...

This time I ditched the flash element, set my D3 up in 5x4 mode and recreated the initial fault. Progress, I thought, so I then gelled the lights to daylight, changed the exposure to a longer exposure based on a combination of incidence and reflection measurements with a light meter - ran a polaroid and it was fine. Spot on for exposure. So I committed two sheets to slightly bracketed exposures and they came back identical to the others - exactly the same deep orange cast and the underexposed, it was as if the gels were not there.

So, have I got a bad batch of film? It is in date, but has come from Germany in to England and it has probably been scanned with some new x-ray or penetrating system. Could this be producing this ridiculously frustrating problem. Or, is it a duff lab?

Your thoughts, experience and wisdom on this matter would be deeply appreciated.

Thanks in advance.