[can-talk] Discussion questions

Rose-lee, motion picture does need cool to cold, low'ish %RH storage. 
Motion picture film conditions are covered in the same ISO Standard 
18911:2000 as other photographic materials. These are quite low the 
"warmest" set of conditions is 7oC & 20-30%RH and the lowest -10oC & 
20-50%RH. You do not mention if these are b&w or colour, colour film from 
this era uses colour dyes that are quite unstable, especially compared 
with new photographic dyes and so the colder the storage conditions the 
better. Below 0oC is fine, if not preferable, however preparation for 
sub-zero storage requires some additional care.

Basic preparation for storage is to firstly rewind the film to a slightly 
lower tension than a projector take-up would wind to. There are several 
reasons for this including shrinkage during storage, cross-linking of the 
emulsion and backcoat and this loose wind assists in off gassing 
decomposition by-products (film is cellulose acetate and will release 
acetic acid which autocatalyses the decomposition reaction). If you are 
not storing below 0oC then you should not use a plastic bag to wrap the 
film* (likewise ALL other objects such as paper receipts etc should be 
removed from the can as well) and do not let a rubber band within 300km of 
the film! Use film splicing tape to hold the film end down if necessary. 
The film can should be made of inert material, the new plastic cans from 
Tuscan and others, steel or aluminium are excellent - as long as the metal 
cans are not painted (powder coated or anodised is OK). Don't tape the can 
shut, there needs to be some air exchange between the filmcan microclimate 
and the rest of the world.

*The exception to not wrapping the film in plastic bags would be if you 
were using Kodak's Molecular Sieve. Mol Sieve is a strong desiccant and 
sorbent and sorbs the acetic acid and maintains a low %RH inside the bag, 
if the film were not bagged then the Mol Sieve would exhaust very quickly. 
Details are on the Kodak website (www.kodak.com). In theory any desiccant 
would do however Kodak have gone to the trouble of working out how much is 
needed per film and putting it in a nice little bag.

If you are storing below 0oC then all of the above plus acclimatise the 
film for 24-48 hours at around 20oC &50%RH along with some A4 sized acid 
free card. Place the film inside the can inside a polyethylene bag, seal 
the bag and then place this bag and a sheet of the acclimatised card 
inside a second bag and seal this as well. Write lots of nice labels on 
the bags so you can see what is inside. Throw/gently place the package in 
the freezer. Removing the film from the freezer requires a gentle thermal 
acclimatisation, leaving the unopened bags in a small foam esky for a day 
or two before opening the bags should be fine.

Contact me off list if you like to discuss this further.

mick

Mick Newnham
Senior Researcher
National Film and Sound Archive
McCoy Circuit, Acton Canberra ACT 2601

Tel: +61 2  6248 2118  Fax: +61 2 6262 5693

www.nfsa.afc.gov.au

The National Film and Sound Archive collects, preserves and provides 
access to Australia's historic and contemporary moving image and recorded 
sound culture.  We are part of the Australian Film Commission.

Arc is here - the National Film and Sound Archive's new state of the art 
cinema with unique pre-show light and sound display, screening the finest 
selection of Australian and world film.  Visit 
http://www.nfsa.afc.gov.au/whats_on/arc for screening times and ticketing 
information, and join our subscribers list to receive your calendar.  The 
NFSA's new cafe, The Studio, is now open during the day plus before and 
after Arc screenings.  The perfect venue for light meals and fantastic 
coffee, in beautiful art deco surrounds.





"Adventist Heritage Centre" <heritage at avondale.edu.au>
Sent by: can-talk-bounces at collectionsaustralia.net
17/01/2008 04:58 PM
 
        To:     <can-talk at collectionsaustralia.net>
        cc: 
        Subject:        [can-talk] Discussion questions



Hi

 

I have two question for everyone.

 

1. We have a number of 16mm motion picture films 1950s+ which I understand 
need to go into cold storage.

What temperature range should we aim for? 

Can they be stored below 0 degrees?

Comments welcome

 

2. I understand they also need to be sealed to avoid moisture getting into 
them

Has anyone any experience in this area.  

Comments welcome.

 

Rose-lee Power

Curator

Adventist Heritage Centre

Cooranbong  NSW 2265
_______________________________________________________________

You are subscribed to the can-talk mailing list:
can-talk at collectionsaustralia.net

To manage your options or unsubscribe visit:
http://lists.collectionsaustralia.net/mailman/listinfo/can-talk

_______________________________________________________________

Discussion list postings are not endorsed by the
CAN Coordination Unit, the Cultural Ministers
Council, nor the Australian Government.
_______________________________________________________________


-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.collectionsaustralia.net/pipermail/can-talk/attachments/20080118/1f7df066/attachment.html