Frozen Pan-X exp'90

[George Mann]

I am getting ready to buy a bundle of Pan-X which has an expiration date of 12/90. Seller claims it was always frozen.

Any particular risk in buying it?

 

[George Mann]

Oops. Misread info. The price is for one roll ($42 with shipping).

 

[wiltw]

Cosmic rays penetrate even freezers...so their can be some fogging of film due to cosmic rays. Lower sensitivity of Pan-X (compared to Tri-X) might be of benefit in reduction of affects of cosmic rays, but that is beyond my knowledge.

 

[George Mann]

So Tri-X is prone to fogging?

 

[George Mann]

There is a 50ft roll of Pan-X exp 9/88, with no details on how it was stored (waiting back from seller).

How many 12exp rolls can I make from this?

 

[wiltw]

Test reports exist for cosmic rays, such as film subjected to a lot of airplane travel. But the reports I have found are only for color neg and color transparency film.

OTOH, from a practical point of view, there have been tests showing little difference between film buried deep underground vs. that stored more conventionally, and little observable difference could be seen. So while Kodak has mentioned cosmic rays, and the fact that they generally cannot be stopped, (some go thru the Earth), the difference that it might make to film fogging seems to perhaps be an academic discussion.

Mile High Fog ? - Does Air Travel Affect Your Film ?

Probably the worst timed post I've ever done because the world is currently grounded. But unless you've been hiding under a rock, you'll no doubt be aware that flying poses a risk to your camera

austerityphoto.co.uk

In a study published in 1936, http://www.cloudylabs.fr/wp/wp-cont...avy-Component-of-the-cosmic-ray-radiation.pdf

"In the 8500 photographs, a total of 80 tracks were observed that showed a markedly heavier ionization than an electron track."​

Not exactly a high degree of affect...just under 1% observable!

A kodak statement on the topic, in the context of cinematography
https://archive.org/stream/Cinemato...de_Kodak_Motion_Picture_Camera_Films_djvu.txt

"10 9/00​

​

Ambient-Background Radiation​

(effects on raw stock)​

​

Ambientgamma radiation is composed of two sources: a​

low-energy component which arises from the decay of​

radionuclides and a high-energy component which is the​

product of the interaction of cosmic rays with the earth's​

upper atmosphere. The radionuclides responsible for the​

low-energy photons exist in soil and rock and are carried​

into earth-derived building materials, such as concrete.​

Upon exposure to ambient-background radiation, photo-​

graphic negative materials can exhibit an increase in​

minimum density, a loss in contrast and speed in the dark​

areas, and an increase in granularity. The changes in film​

performance are determined by several factors, such as​

the film speed and length of time exposed to the radiation​

before the film is processed. A film with an exposure​

index of 500 can exhibit about three times the change in​

performance as a film with an index of 125. While this​

effect on film raw stock is not immediate, it is one reason​

why we suggest exposing and processing film as soon as​

possible after purchase. We recommend a period of no​

more than six months from the time of film purchase​

before processing, provided it has been kept under spec-​

ified conditions. Extended periods beyond six months may​

affect faster speed films as noted above, even if kept​

frozen. The only way to determine the specific effect of​

ambient-background radiation is with actual testing or​

measurements and placing a detector in the locations​

where the film was stored. The most obvious clue is the​

observance of increased granularity, especially in the light​

areas of the scene."​

 

[Sirius Glass]

There is a 50ft roll of Pan-X exp 9/88, with no details on how it was stored (waiting back from seller).

How many 12exp rolls can I make from this?

100 feet of Ektachrome made 18 rolls of 36 exposures. You have to calculate for shorter rolls and leads.

 

[George Mann]

I have seen threads on this forum stating that Pan-X never goes bad regardless of how it is stored.

Just how true is this?

 

[braxus]

George, it is mostly true yes. I've used rolls of this film stored in every which way and for the most part, you get usable, if not good, results from it shot at 32 ISO. The worst Pan X I've used was a 100 foot roll that the grain on the film was rather large for its speed, but other than that, it was quite usable. I wouldnt worry about it and just shoot it.

 

[Andrew O'Neill]

Ooh that reminds me. I've got that 4x5 box of Pan-X expired 62 years ago, that I need to play around with...

 

[Sirius Glass]

I have seen threads on this forum stating that Pan-X never goes bad regardless of how it is stored.

Just how true is this?

The perfect film?

 

[George Mann]

The perfect film?

It doesn't seem to scan very well. But a good analog print from it is something to behold.