How quickly will heat fog B&W film?

[Don_ih]

if Ektachrome can do it, HP5+ can

I suspect Kodak films from 50 years ago were probably more resilient than current HP5. HP5 already fogs pretty quickly with age.

Anyway, I have 2 inches of it in a cassette in an old Kodak aluminum film can in the cupholder in my van. I'll develop it this evening with the similar piece sitting in a film cassette in the darkroom.

 

[rcphoto]

I suspect Kodak films from 50 years ago were probably more resilient than current HP5. HP5 already fogs pretty quickly with age.

Anyway, I have 2 inches of it in a cassette in an old Kodak aluminum film can in the cupholder in my van. I'll develop it this evening with the similar piece sitting in a film cassette in the darkroom.

Your test is about as valid as Franks and my statements. Experiments need to be repeatable and there are too many variables in your test.

 

[Don_ih]

Your test is about as valid as Franks and my statements. Experiments need to be repeatable and there are too many variables in your test.

Variables? Tell them to me. Two pieces of film cut from the same bulk roll, put in light-tight containers at the same time, put in two different environments for the same amount of time, developed on the same reel at the same time. Where are these "variables" you're talking about?

 

[pentaxuser]

I realise cars vary, but I've always found that the boot/trunk is cooler than the cabin as it has no windows.

If you are human then lack of air tended to be the problem with old cars unless Jimmy Cagney was close. Then if you were worried about air and said so, Jimmy gave you air by making some holes in the boot with a revolver. Nice of him, I thought, as he didn't even particularly like the man in the boot.

pentaxuser

 

[logan2z]

Anyway, I have 2 inches of it in a cassette in an old Kodak aluminum film can in the cupholder in my van. I'll develop it this evening with the similar piece sitting in a film cassette in the darkroom.

Very curious to see the results...

 

[rcphoto]

Variables? Tell them to me. Two pieces of film cut from the same bulk roll, put in light-tight containers at the same time, put in two different environments for the same amount of time, developed on the same reel at the same time. Where are these "variables" you're talking about?

Are you trying to determine the effects of film sitting in a car or the effects of temperature on film?

If you’re testing heat effects on film you would want to know what temp the film was at and how long it was at that temp. if you started the test when the car was cool, how long it took to get to test temp. Is the car parked in shade. Did it get any shade during the test. Any clouds in the sky? All of this is going to effect the inside temp of the car and make duplicating the test impossible.

 

[grain elevator]

Anyway, I have 2 inches of it in a cassette in an old Kodak aluminum film can in the cupholder in my van. I'll develop it this evening with the similar piece sitting in a film cassette in the darkroom.

I'm very curious, too! I expect no ill effect from one day and would also be interested in somewhat longer timespans (let's say weeks), if anyone wants to do that... I don't have a car so I can't, but would like to know for when I travel.

 

[Don_ih]

Are you trying to determine the effects of film sitting in a car or the effects of temperature on film?

If you’re testing heat effects on film you would want to know what temp the film was at and how long it was at that temp. if you started the test when the car was cool, how long it took to get to test temp. Is the car parked in shade. Did it get any shade during the test. Any clouds in the sky? All of this is going to effect the inside temp of the car and make duplicating the test impossible.

It should be obvious that this is a non-stringent quick test to see if sitting in a car in sunlight on a hot day, for about 8 hours or so, will have an visible impact on the base fog of hp5. I could load each strip into a camera before I develop and take a test exposure - and I may, if I feel like it.

This forum is overrun by people looking for reasons to do nothing. Well, this will generate a result. My test may not be suitable for getting a sophisticated data set but it will tell you a plain "yes" or "no" and give an idea of severity. In other words, it will answer the question, "Is it ok to leave my film in a car all day long on a hot day?"

I expect no ill effect from one day

I don't expect very much impact from one day, either. I know that when you leave plus-x in a camera in a car through one summer and winter, you end up with emulsion that looks like mud flats.... but surprisingly little increase in base fog.

the side of a car. Should see this through a grain focuser - it's really clear. Zoom of this:

 

[Sirius Glass]

I realise cars vary, but I've always found that the boot/trunk is cooler than the cabin as it has no windows. I cannot see how a few hours or even a few days in a hot car would do what OP describes. There's something else afoot.

What you are stating flies in the face to scientific tests conducted for decades. Feeling that something is true does not make it true.

 

[pentaxuser]

It should be obvious that this is a non-stringent quick test to see if sitting in a car in sunlight on a hot day, for about 8 hours or so, will have an visible impact on the base fog of hp5. I could load each strip into a camera before I develop and take a test exposure - and I may, if I feel like it.

This forum is overrun by people looking for reasons to do nothing. Well, this will generate a result. My test may not be suitable for getting a sophisticated data set but it will tell you a plain "yes" or "no" and give an idea of severity. In other words, it will answer the question, "Is it ok to leave my film in a car all day long on a hot day?"

Don, it sounds like a reasonable attempt to carry out a test to me. Yes your conditions might be different from other conditions but a broad brush answer is at least an indication of what might happen or not happen

pentaxuser

 

[MattKing]

Let's call it an interesting experiment, and agree not to argue about what exactly can be concluded from the results.
At least with HP5+ (I assume it is the current HP5+, and not HP5) you won't have to worry about colour shifts.
FWIW, improved stability in non-refrigerated storage was one of the design goals when Ektachrome was recently re-introduced by Kodak. That was a recognition of the fact that there is much less climate control involved in the current distribution network, plus an acknowledgement that master rolls might have to be kept longer between slitting and finishing runs.

 

[BrianShaw]

It should be obvious that this is a non-stringent quick test to see if sitting in a car in sunlight on a hot day, for about 8 hours or so, will have an visible impact on the base fog of hp5. I could load each strip into a camera before I develop and take a test exposure - and I may, if I feel like it.

This forum is overrun by people looking for reasons to do nothing. Well, this will generate a result. My test may not be suitable for getting a sophisticated data set but it will tell you a plain "yes" or "no" and give an idea of severity. In other words, it will answer the question, "Is it ok to leave my film in a car all day long on a hot day?"

Don, it sounds like a reasonable attempt to carry out a test to me. Yes your conditions might be different from other conditions but a broad brush answer is at least an indication of what might happen or not happen

pentaxuser

Looking forward to your results! [edit: Oh, sorry. "Messed up quote" made me think you were also going to perform such a test. Thanks for your support of Don's efforts!] And Don's, also. Please test the difference between the passenger compartment and trunk boot. Is your weather hot enough for a valid test, though?

 

[Agulliver]

It's not that I "do nothing". I have carried data logging equipment around in the car (for work purposes) and I know the boot is cooler than the cabin after hours in the sun. I've also quite commonly left a camera bag with cameras and film in the car for hours or days at a time in hot sun...not just in benign old England but Arkansas, Missouri, Arizona, Spain, Greece.....and while I did not perform detailed tests I saw no effect on the negatives - colour or B&W.

Film is a product that is literally designed to sit in non climate controlled conditions for several years and perform as if it just left the factory. Heat surely does speed up the chemical reactions that can cause film to deteriorate but we're talking weeks and months, not a road trip. Hell, if that ruined film then just think of it in haliage trucks, on container ships etc.

 

[Don_ih]

Film is a product that is literally designed to sit in non climate controlled conditions for several years and perform as if it just left the factory.

I said above that I don't expect much of a difference - if any difference. And I can only assess it by visual inspection. I haven't developed the strips yet - and I think I'll use each to take a photo (same photo) to see if there's a difference in sensitivity.

My point is, while it's great to base an opinion on what you believe and what you've been told (or based on what makes sense), if a simple test can easily decide the matter, why not do it?

 

[logan2z]

I shot another fresh roll of HP5+ in the same camera yesterday and developed it the sane way (dilution, temp, time) and the negatives look fine.

I'm not sure what happened to the previous roll but storing it in a hot car was the only significant difference I could come up with.

At this point I'm going to take my wife's advice and "chalk it up to heat and move on". Yes, she's getting tired of hearing me talk about it

 

[Don_ih]

Top strip is the one that was in the van from yesterday morning until this morning, through a very hot day.
Bottom strip was in the darkroom.
Both exposures identical, made this morning. Strips developed together in stock D76.
I can't see any impact the heat had, except the strip that was in the car was more-tightly coiled when I put it on the reel.

 

[Sirius Glass]

Top strip is the one that was in the van from yesterday morning until this morning, through a very hot day.
Bottom strip was in the darkroom.
Both exposures identical, made this morning. Strips developed together in stock D76.
I can't see any impact the heat had, except the strip that was in the car was more-tightly coiled when I put it on the reel.

View attachment 348315

I would not expect any change with only one day exposure to high heat.

 

[logan2z]

Top strip is the one that was in the van from yesterday morning until this morning, through a very hot day.
Bottom strip was in the darkroom.
Both exposures identical, made this morning. Strips developed together in stock D76.
I can't see any impact the heat had, except the strip that was in the car was more-tightly coiled when I put it on the reel.

View attachment 348315

Thanks for running the experiment. I'm not sure what happened to my film, whether it was heat or something else. As I mentioned above, I ran another roll of the same film through the same camera yesterday and developed it exactly the same way. As a sanity check, I first tested the developer to make sure it was still good and it was. The negatives look fine this time around.

 

[Doremus Scudder]

Even so the trunk and glove box get even hotter.

With my white car, the trunk is the coolest place on hot days. The car windows turn the car into a greenhouse; heat can't escape, so the interior of the car is always hotter than the trunk, which has a nice reflective lid and no windows.

Doremus

 

[250swb]

If the film has been exposed get it processed asap because exposure triggers image degradation (and this is so anyway for many films and especially higher ISO films). Otherwise unexposed film can last a long time in a hot car, assuming you know it's there and haven't forgotten about it entirely. I keep a Pentax Spotmatic in the boot for 'just in case situations' loaded with Delta 400 or HP5. I've used it on and off over the Spring and Summer and just processed the film and it's all perfect. I'd be worried it it was a 1600 or 3200 ISO film, but 400 is stable enough to abuse a bit.

 

[Don_ih]

If the film has been exposed get it processed asap because exposure triggers image degradation

That could be a useful second experiment - see if there's an impact on an exposed image. I could do that, also. That could explain what happened to your images, @logan2z.

 

[logan2z]

That could be a useful second experiment - see if there's an impact on an exposed image. I could do that, also. That could explain what happened to your images, @logan2z.

Ahh I must have misunderstood your original experiment, that's what I thought you did. But I re-read your posts and I see you put the unexposed film into the hot car and then shot the image(s). I had stored the exposed film in the car. I suppose that could make a difference.

 

[MattKing]

Near the end of the more intensive Kodak film R & D error, they developed a very high speed film process that used heat to develop the image.
For a number of reasons, it was impractical to market it.
Yes - the image on exposed film is likely to be more vulnerable to heat.
But as to how to quantify that vulnerability.....?????

 

[Don_ih]

But as to how to quantify that vulnerability.....?

You don't need to. If leaving it in a hot car all day has a bad impact, no matter how bad, don't do it (or at least try to avoid it).

Quantifying the vulnerability doesn't really concern a user - it would be something a manufacturer or seller would like to know, probably. But a user simply needs to know that X can cause Y.

I'll know more in a couple of days. I just put the new strip in my van but I won't be developing it until Thursday evening or maybe Friday. It can stay in there until then.

I must have misunderstood your original experiment, that's what I thought you did.

No - I just wanted to see if heat would make fog -- and then I wanted to see if it would impact the sensitivity.

 

[logan2z]

No - I just wanted to see if heat would make fog -- and then I wanted to see if it would impact the sensitivity.

Got it. Looking forward to seeing the results of your second experiment.