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» 8mm Forum   » 9.5mm Forum   » Curling Pathescope Film

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Author Topic: Curling Pathescope Film
Paul Adsett
Film God

Posts: 4913
From: USA
Registered: Jun 2003


 - posted August 31, 2017 10:54 AM      Profile for Paul Adsett     Send New Private Message       Edit/Delete Post 
I have noticed that Pathescope film prints have amazing mechanical 'memory' properties. Leave a print threaded on the projector for a few days and the film will assume the shape of the film path! Even more noticeable is the spring-like memory properties of the Baby cassette films, which acts just like a clock spring and is a bear to handle! I wonder why and how Pathescope treated the films to get it this way.

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Maurice Leakey
Film God

Posts: 5784
From: Bristol. United Kingdom
Registered: Oct 2007


 - posted September 02, 2017 11:32 AM      Profile for Maurice Leakey   Email Maurice Leakey   Send New Private Message       Edit/Delete Post 
It may be due to the fact that Pathescope films were printed on cellulose acetate base, a factor determining the longevity of their 9.5mm films.
Care must be taken not to store them in too dry an atmosphere which may cause cupping due to shrinkage of the base material.
I realise that this does not necessarily answer Paul's comment, but I thought it may be of interest.

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Maurice

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Janice Glesser
Film Goddess

Posts: 3403
From: Sunnyvale, CA USA
Registered: Sep 2011


 - posted September 02, 2017 12:39 PM      Profile for Janice Glesser   Email Janice Glesser   Send New Private Message       Edit/Delete Post 
The chemical properties and dryness of the film most likely does contribute to it's spring-like memory. But being encased in those little Baby cassettes for 80+ years is probably the main factor. It's amazing they run through a projector at all. As you mention Maurice... the cupping can inhibit even focusing and the twisting makes splicing and editing very challenging. However, I get a feeling of wonder every time I project one of these films.

[ September 02, 2017, 02:13 PM: Message edited by: Janice Glesser ]

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Janice

"I'm having a very good day!"
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Clinton Hunt
Jedi Master Film Handler

Posts: 845
From: Waharoa,North Island,New Zealand
Registered: May 2010


 - posted September 02, 2017 07:01 PM      Profile for Clinton Hunt   Author's Homepage   Email Clinton Hunt   Send New Private Message       Edit/Delete Post 
This doesn't answer why they curl but ... a while ago I decided to put a few of the cartridge cassettes onto a normal reel so I could project them on my Specto ... and as Janice said ... what a nightmare,really curly at the ends but I persisted and joined them,they project well.

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Cheers from me in New Zealand :-)

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Ken Finch
Jedi Master Film Handler

Posts: 535
From: Herne Bay, Kent. U.K.
Registered: Oct 2011


 - posted September 04, 2017 02:54 PM      Profile for Ken Finch   Email Ken Finch   Send New Private Message       Edit/Delete Post 
Oh yes Clinton, it is a nightmare. Many years ago I agreed to join some family films together to be shown at the birthday celebration of someones 90 year old granny. When receiving the films I discovered they were all in 30ft cassettes, 900ft of them. As you say all like watch springs and difficult to join. No tape splices in those days. It was very hard to keep them flat on the splicer. Ken Finch [Razz]

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Dino Everette
Phenomenal Film Handler

Posts: 1535
From: Long Beach, CA USA
Registered: Dec 2008


 - posted October 08, 2017 10:43 PM      Profile for Dino Everette   Email Dino Everette   Send New Private Message       Edit/Delete Post 
My opinion is that it is a combination of the fact that old films experience shrinkage, and that they are inside metal cassettes, which will amplify the heat on the film which has been stored in environments that switch from cold to hot conditions. I have seen hundreds of 16mm prints that have been stored in warmer conditions over the years and they exhibit the same sort of "permanent" curl...Basically storing films in cans in houses that have varying temperatures throughout the years can be risky, as the metal cans amplify the changes...At work I once came across the greatest single longterm test case ever....It was a box of 35mm trailers that came straight from the lab in 1973 to the person's house. The person stuck the box in their closet and it sat there for 45 years until we picked it up at the archive. Inside the box were 12 copies of a trailer, 11 of which were in metal cans, and one was in a cardboard box..The 11 were all terribly deteriorated with extreme vinegar syndrome, brittle and shrunken, and the one in the box was in perfect condition...Metal is great for archives that store films in the cold, but terrible for the home, which may have large temperature changes throughout the year...The boxes breathe in such an environment where the metal cans just work harder to ruin the film by increasing the change in temperature. If the house is 75 degrees, it is probably 80+ inside the can, or if the house is 60 it is probably 55- in the can...in the archive it is the opposite because the boxes can easily develop mold or problems if the air quality is not kept dry...

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"You're too Far Out Miss Lawrence"

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