Reversal Underexposure

[Mike Panczenko]

I've been wondering about this for a while.

When you overexpose a negative stock a little, the image is put on the slower layers, so the grain is finer than normal. So, with reversal, would underexposure do the same?

An underexposure would send the image to the higher speed layers, which would then be washed off, leaving only the slower layers on the developed print. So, if you were going to do an IN IP process, could you underexpose the reversal and get a finer grained image?

[John Pytlak RIP]

In any color film, underexposure usually puts the shadow densities on the faster emulsion components that have the larger grains. But a reversal color film then re-exposes/fogs the unexposed silver halide grains, so the opposite side of the scale is used to form the dyes.

 

In general, try to expose color reversal films "normally". But better to err on the side of slight underexposure, as overexposure will cause the highlights to fall on the "toe" of the reversal characteristic.

[Mike Panczenko]

But because the faster, larger grained layers are exposed, and then washed off, leaving only the fine grained layers to get the second exposure, would this create a finer grained image, akin to overexposing in negative films?

[John Pytlak RIP]

In a reversal film, it's a mix of the two, and so very dependent on curve shape and exposure of the particular film.

[Mike Panczenko]

Ahh, I see. Thank you John.

[Dominic Case]

Another point with reversal is that you have less latitude: so whatever happens to the grain if you underexpose (or overexpose for that matter) you will degrade the shadow (or highlight) detail more than you would for the same exposure change on negative.

 

As John says - aim for correct exposure with reversal.

[Marty Hamrick]

I have shot ECO under by 2 stops and printed up,once by accident and once on purpose.I noticed an increase in grain and contrast,but deeper color saturation particularly in reds.

I know some still photographers,particularly folks that shoot a lot of skin tones (gallery type nudes,fashion and jewelry stuff) who shoot reversal slide film and purpsely underexpose for those reasons.

Marty