Delta 100 4x5 B&W exposure compensation for high temperatures?

[KerryEmery]

Can anyone tell me if temperature of the film is a factor when exposing the film? I would think it might be. I'm in Florida at average 90 degrees this time of year. With film in the trunk in insulated cooler it still reaches upper 80's to 90. I keep it out of direct sun as much as possible to avoid even higher temps. I know it matters during development but am unclear and unable to glean any information on the web so far on exposure temperature. Data sheets for Delta 100 4x5 makes no mention of it.

[Mark Barendt]

No exposure compensation that I know of.

[polyglot]

No, unless you go to extremes of cold... but we're talking extremes that you won't survive. Ignore temperature for exposure purposes.

The reason it matters for development is because that's a chemical reaction, the rate of which will vary with temperature. Exposure of the film is a discrete electrical phenomenon where a photon kicks an electron into a different energy band, and it has practically nothing to do with temperature. The only difference would be if you raise the temperature of the film, you could perhaps get sensitivity into slightly longer wavelengths (lower energy photons) but the temperature required is going to melt the emulsion and your camera before the effect even begins to be measurable.

[Brian Ellis]

I lived and photographed in Tampa and surroundings in all seasons (both of them) for many years. I never found it necessary to adjust for the heat (or the cold : - ))

[IanG]

I've used Delta 100 in tempertures over 40°C (104°F) many times in Turkey and Greece, exposures tend to be close to the maximum my meters will read but it behaves wonderfully :D So does HP5+ which I use for handheld LF work.

Ian

[Bruce Watson]

Can anyone tell me if temperature of the film is a factor when exposing the film? I would think it might be.

But it's not. The formation of a latent image is pretty much temperature independent, within reason. If you can survive in the environment where the photograph is being made, so can the film/latent image.

[KerryEmery]

But it's not. The formation of a latent image is pretty much temperature independent, within reason. If you can survive in the environment where the photograph is being made, so can the film/latent image.

Thanks to all. It is as I suspected. Nice to get a majority opinion. I'm in Clearwater - so I will shoot away! Thanx again.