NPS negs came out red!

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I'm new to this so bear with me please. I bought a Tech III in good condition w/ Schneider 150mm. First batch of sheet film was NPS. Exposures ran from 1/20 to 1/200 at f 16 - f 32. All shot outdoors in good sunlight. I metered w/ my Nikon 6006. All exposures came out very red. Lab assumed I had used a red filter but I hadn't. Film was brand new from B & H. I had kept the film in the freezer for a week before using it. Does NPS turn red if exposures are too long? What is effect of reciprocity on NPS? Anyone have any ideas?

-- Bill Howe (Howehoppe@aol.com), February 28, 2000

Answers

NPS is a color neg film, if I am thinking correctly. If so, a red filter would turn the negs the opposite color. I may be wrong, but I have a feeling the lab screwed up. Why not try a couple of other shots under the same conditions and send to another lab or perhaps the same one and let them try again. Was it a pro lab? Was the color the same at the edges where the holder marks are? Have you removed the lens and made sure there isn't a filter on the back of the lens? Sounds like chemistry problem to me. Doug

-- Doug Paramore (dougmary@alanet.com), February 28, 2000.

If your shutter speeds were from 1/20 sec to 1/200 sec., then reciprocity should not be a problem.

-- Ron Shaw (shaw9@llnl.gov), February 28, 2000.

I would think as Doug that your lab had a problem. On the border of the films are preexposed codes. They can serve as test to check if the film was correctly processed. But you would have to compare with a correctly processed sheet, or send them to Fuji Film for inspection.

-- Paul Schilliger (pschilliger@vtx.ch), February 28, 2000.

Are the images negatives? I once had a lab run some neg film through an E6 line, and I got red/orange transparencies back.

-- Glenn C. Kroeger (gkroeger@trinity.edu), February 28, 2000.

Is it possible that the film was in the holders back to front? If so, the negs should also be about two stops underexposed.

-- Struan Gray (struan.gray@sljus.lu.se), February 28, 2000.


I am not sure about negs., but if you put a chrome in upside down, after processing it turns red... I would check that first...

-- Bill Glickman (bglick@pclv.com), February 28, 2000.

If the lab thought a red filter had been used, the prints must have been too red, not the negatives. This implies that only the red-sensitive layer received significant exposure, which is exactly what happens when you expose either negatives or slides through the base of the film. Detail on the negative will be a bilous green colour from a mixture of the cyan (developed red sensitive) layer and the orange mask.

The easiest way to check without trying to second guess if the exposure was correct is to see if the negatives are mirror reversed. Hold the film with the emulsion away from you (long edge vertical and the notches at top *left*): if you see a mirror image you had the film loaded backwards.

-- Struan Gray (struan.gray@sljus.lu.se), February 29, 2000.


From my experience with photofinishing red negatives or (otherwise off color from the base towards the red) are heat damaged. If the film was shipped to you then it could have been heat damaged in transit. I have never seen a chemistry problem that would cause the negatives to be red. If the negatives look okay then it was a printing problem that can be easily corrected or it may have been printed on paper that was heat damaged. Did you ask for prints on a special surface of paper? Get your negatives printed at another lab if they look okay. Chances are you had an inexperienced lab tech try to print them...

-- Troy Branch (varasoph@aol.com), March 03, 2000.

Frequently this happens when the film is loaded upside down with the film base towards the lens. Good luck.

-- Geoffrey Ithen (gifoto@aol.com), March 14, 2000.

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