[Leica] FS: Film from the freezer
John Nebel
john.nebel at csdco.com
Thu Oct 1 19:19:02 PDT 2015
In 20 years, cosmic rays may have slightly fogged the ASA 400 film, be
interesting to see. Worth a go anyway.
"Ambient Background Radiation (Effects on Raw Stock
Ambient gamma 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. Lead shielding or storage
deep underground may be helpful, but for long-term raw stock storage,
radiation will still be a factor. Upon exposure to ambient-background
radiation, photographic materials can exhibit an increase in minimum
density, a loss in contrast and speed in the toe, and an increase in
granularity.
The change in film performance is 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 (El) of 500 can exhibit
about three times the change in performance as a film with an El of 125.
While this effect on a film product isn't immediate, we still suggest
exposing and processing the film soon after purchase. We recommend a
period of no more than six months from the time of film purchase before
exposure and processing, provided it has been kept under specified
conditions. Films kept for extended periods beyond six months may be
affected, especially the faster films, even if they have been frozen.
The only way to determine the specific effect of ambient-background
radiation is to make actual tests or measurements by placing a detector
in the location where the film is stored. The most obvious clue is the
observance of increased granularity, especially in the light areas of
the scene."
<http://motion.kodak.com/motion/Support/Technical_Information/Storage/storage_info.htm#radiation#ixzz3nNB04BHX>
On 10/1/15 6:07 PM, Richard Man wrote:
> Ken, I will take them.Please send paypal/address info.
>
> Thanks
>
> On Thu, Oct 1, 2015 at 10:13 AM, Kenneth Lassiter <kenlass904 at gmail.com>
> wrote:
>
>> As part of my downsizing, I must remove my stash of film from the freezer.
>> Thi sfilm was fresh when it was put into the freezer 20 years ago. It
>> should be perfect when warmed to room temperature. It has been stored in
>> the plastic cans inside freezer bags inside a large plastic container and
>> always in the freezer.
>>
>> Price REDUCED:US$60 for the lot of 115 rolls including shipping in the USA.
>>
>> OR US$0.75/roll plus shipping.
>>
>> *# Rolls*
>>
>> *Film*
>>
>> *135-36 exp*
>>
>> *135-24 exp*
>>
>> 25
>>
>> Ektachrome 200 Daylight
>>
>> X
>>
>>
>>
>> 26
>>
>> Ektachrome 100 VS
>>
>> X
>>
>>
>>
>> 15
>>
>> Fuji 100 Daylight slide film
>>
>> X
>>
>>
>>
>> 7
>>
>> Fuji 400 Provia
>>
>> X
>>
>>
>>
>> 4
>>
>> Ilford Delta B/W
>>
>>
>>
>> X
>>
>> 7
>>
>> Kodak Supra 100 Color Neg
>>
>> X
>>
>>
>>
>> 5
>>
>> T-max 400
>>
>> X
>>
>>
>>
>> 8
>>
>> Fuji Sensia 200 slidefilm
>>
>>
>>
>> X
>>
>> 5
>>
>> Kodak Porta 400 NC
>>
>> X
>>
>>
>>
>> 4
>>
>> Kodacolor Gold 200 Color Neg
>>
>>
>>
>> X
>>
>> 1
>>
>> Kodak IR Ektachrome Prof
>>
>> X
>>
>>
>>
>> 3
>>
>> Kodak Max 400 color neg
>>
>>
>>
>> X
>>
>> 10
>>
>> Misc mixed single rolls
>>
>> X
>>
>> X
>>
>> *115*
>>
>> *Total rolls*
>>
>>
>>
>>
>>
>> Ken Lassiter
>> kenlass904 at gmail.com OR 561-247-7725
>>
>> _______________________________________________
>> Leica Users Group.
>> See http://leica-users.org/mailman/listinfo/lug for more information
>>
>
>
>
More information about the LUG
mailing list