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Heat damage to negatives?


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Has anyone seen this grain pattern in scans from negatives before?  Shot on Tri-X on an M-P with 50mm APO Summicron-M 

The film was processed and scanned by a shop that said "we've seen this before only in summer and only on black and white film when it was exposed to extreme heat"

I was in Greece, it was hot but not in an EXREME way, maybe the camera sat in the sun for an hour or two during the day at 85 degrees F.

Anyone have any thoughts or experience on this?  Crops below to highlight obvious areas of the flecked pattern.

Thanks

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From the Kodak  Tri-X fact sheet:

Quote

High temperatures or high humidity may produceunwanted quality changes. Store unexposed film at 24°C (75°F) or lower in the original sealed package. Always store film (exposed or unexposed) in a cool, dry place. For best results, process film as soon as possible after exposure.

You probably had the film close to the boiling point of water.

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The reticulation process is a bit more like clay beds that dry out in the sun and form a pattern of cracks as the clay shrinks.

https://www.alamy.com/stock-photo/cracked-dried-river-clay-bed.html

But yes, in film it is an effect of uneven temperatures during processing, and going from a very warm bath into a relatively cold bath. The warm bath expands the gelatin, and the cold bath shrivels it rapidly, resulting in a "craquelure" pattern embossed into the gelatin. Which also means more or less silver, in a network pattern.

https://en.wikipedia.org/wiki/Craquelure

It is pretty rare in modern film, which has been engineered with tougher gelatin. Requires (usually) about a 50°C "shock" temperature change. A pain for photographers who like to do it intentionally for artistic effect.

https://www.ilfordphoto.com/unleash-that-reticulated-film-python/

High ambient temperatures, such as being left in a parked car under sunshine and "baked" at 40-60°C for several hours, can damage film properties. Especially color film (distorted colors or color casts). It may even increase grain. I've never heard of film gelatin reticulating based on dry heating, however.

Quote

Gelatin withstands dry heat at 100°C for several weeks....

....from https://cool.culturalheritage.org/albumen/library/c20/hendriks1.html

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I agree with the idea it's reticulation during processing, either a big change in temperature between solutions or a drying cabinet set to 'afterburner' mode. The 'thinner' parts of the emulsion appear more affected than the higher mid-tones and highlights. I've had a half used roll of Tri-X loaded in a P&S camera sat in my car glove box for three or four years before I finished the roll and processed it and there was no damage to the emulsion. It may only be in UK temperatures but it still gets very, very hot in a closed car in the Summer. It's also harder than you think to accidentally reticulate film during the developing but pretty easy if its then plunged into freezing or hot wash water.

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1 hour ago, 250swb said:

It may only be in UK temperatures but it still gets very, very hot in a closed car in the Summer.

Still, putting something out in the sun gets it a lot more hot than ambient temperature does. That is demonstrated by Solar heaters, which work fine on a cool day with clear sunshine, but not on a cloudy hot day.

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I had a film back from a UK lab that I had used many times before. It exhibited similar results to that shown. when I challenged the lab they claimed it was my fault for using out of date film. However, 1. the film wasn't out of date and 2. a film from the same batch that I processed myself was fine. Needless to say I no longer deal with that lab. I normally process my own B/W film but due to moving house I used this lab which I normally used only for colour film. Home processing back up and running now.

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Posted (edited)
13 hours ago, homertruck said:

Has anyone seen this grain pattern in scans from negatives before?  Shot on Tri-X on an M-P with 50mm APO Summicron-M 

 

Yeah it looks like reticulation.

This happens most commonly with big temperature changes during development. For instance someone might develop at 24ºC, but for the stop bath (that doesn't play a role in development), they might use very cold tap water, say 4ºC. That huge change in temperature causes a rapid contraction to the gelatin of the emulsion, which develops micro tears.

(Far) Less commonly, it could happen from extreme heat in the negative, as the lab said. Same reason kinda, extreme heat will expand and stretch the gelatin a lot, more than it can take, so it'll develop micro tears.

Edited by giannis
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Posted (edited)
10 hours ago, jaapv said:

Still, putting something out in the sun gets it a lot more hot than ambient temperature does. That is demonstrated by Solar heaters, which work fine on a cool day with clear sunshine, but not on a cloudy hot day.

The sun does shine in the UK despite what the EU would hope for. If you look at prevailing weather patterns your weather is often our second hand weather

Edited by 250swb
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That is absolutely correct, warm and sunny weather comes from Germany, cool and sunny weather comes from Scandinavia, thunderstorms come from France  and gloomy rain and storms come from the UK. I had hoped for an improvement with Brexit, but unfortunately your government appears to be quite inefficient at keeping British weather in line. Canutes, the lot of them.

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85 F is nothing special these days. Even in Canada and Russia. 

I was regularly taking exposures on all kind of films in these and higher temps. No problems. 

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Can you post a photo of the the negative. My guess the negatives are darker than usual which can be judged from the color around unexposed part of the film. I have the same problem to many of my Kodak BW films imported from the US. Some rolls that I hand carry do not exhibit this issue.

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12 hours ago, ekindangen said:

My guess the negatives are darker than usual which can be judged from the color around unexposed part of the film.

This is from xray scanners. But I thought film is marked accordingly, when bought from established manufacturers, not not go through such scanners at airports when shipped.

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5 hours ago, giannis said:

This is from xray scanners. But I thought film is marked accordingly, when bought from established manufacturers, not not go through such scanners at airports when shipped.

When shipped via DHL or Fedex it's out of control whether they run them thru high power xray machine or not. Maybe that's why handcarry films survive better.

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2 minutes ago, ekindangen said:

When shipped via DHL or Fedex it's out of control whether they run them thru high power xray machine or not. Maybe that's why handcarry films survive better.

Yeah could be. But I thought they had some sorts of system in place to avoid that, when it's obvious that it's film which will be damaged by such scanners. When ordering film online, in bigger orders, I've noticed the outer cardbox comes with big stickers saying "Photographic film - DO NOT X-RAY". Maybe it's not universal though.

About the carry on scanners you're right, but unfortunately they started replacing those with big CT-style scanners that are more comparable to the checked in luggage scanners, and will definitely affect film quite visibly. I've noticed it myself, I was scratching my head why I get such dense negs with fog and grain quite higher than normally. Until I figured the only common denominator in the fogged/grainy negs was that they all passed through one of the new CT-style hand luggage scanners. Hadn't thought of that initially because never had an issue with hand luggage scanners. Turns out the modern ones ruin even slow film, even Kodak issued a warning.

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1 hour ago, ekindangen said:

When shipped via DHL or Fedex it's out of control whether they run them thru high power xray machine or not. Maybe that's why handcarry films survive better.

Or you could Google 'reticulation' and compare the identical patterns in the emulsion with those posted by the OP. Here for an example is an article by somebody who actually wants reticulation to occur

https://www.ilfordphoto.com/unleash-that-reticulated-film-python/

 

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1 hour ago, giannis said:

Yeah could be. But I thought they had some sorts of system in place to avoid that, when it's obvious that it's film which will be damaged by such scanners. When ordering film online, in bigger orders, I've noticed the outer cardbox comes with big stickers saying "Photographic film - DO NOT X-RAY". Maybe it's not universal though.

About the carry on scanners you're right, but unfortunately they started replacing those with big CT-style scanners that are more comparable to the checked in luggage scanners, and will definitely affect film quite visibly. I've noticed it myself, I was scratching my head why I get such dense negs with fog and grain quite higher than normally. Until I figured the only common denominator in the fogged/grainy negs was that they all passed through one of the new CT-style hand luggage scanners. Hadn't thought of that initially because never had an issue with hand luggage scanners. Turns out the modern ones ruin even slow film, even Kodak issued a warning.

Yes - That works about as well as "Fragile-handle with care"  🙄

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