Why does (some) film curl?

???

 

My first 2 rolls of EFKE R50 dried with different degrees of curl.

This one was glad to spiral when I removed the bottom film clip. I

bet it takes a week under a book to make these flat enough to wrangle

into my negative carrier.

 

Recently, I started using SFX in 120 as well, and it likes to get a

bit curly. Delta 100 behaves pretty well.

 

Usually, I process in PMK, followed by 3-4 water changes with

agitation, then fix in TF-4 for 5-6 minutes. Then I dump the PMK back

in, for one minute with agitation, then the series of six 5-minute

rinse/soak things. I use LFN as a wetting agent, and distilled water

for EVERYTHING film-related. Recently, I've cleaned out 2 stores of

their distilled water supply (at $0.89 a gallon, I'm damn well going

to buy it all because I use at least 2 gallones daily)

 

Curly film not appreciated. Anyone got any ideas??

 

Ah - I've taken to drying film here, in a closet in my apartment. I

will bring a pot of boiling water into the closet right before I

start developing, and remove it about 20-30 minutes before I bring

film in there, so the humidity can dissipate again. It's been so dry

in here (25% humidity this morning) that I feel this need to weigh

down the dust particles with steam. Hm. Can't remember who

recommended that technique, but it does work for dust-free-ness. Er.

Gallones indeed.

Try taking your dry film and putting it back on a developing reel overnight. Put it on emulsion side out to reverse the curl. Might help. Some brands of film just like to curl more than others. When Kodak first came out with 2475 Recording Film in 35mm cassettes about 30 odd years ago I thought they bought their film base from a Slinky factory.

I usually wrangle it into the neg carrier anyway, and put it into my filing system. Within a couple of months, the film will usually be pretty flat.

 

-Scott

There are a few different factors that may contribute to the amount of curl that you may see: The rate at which you remove moisture from the emulsion/film and the charactersitics of the film support and it's dimensionally stability. If moisture is removed too quickly, you will find that this tends to increase the amout of curl. Keep in mind too that different film manufacturers use different types of film support--Estar, Acetate, etc.--and these different materials will react in their own way when it comes to drying or overall dimensional stability. The humidity level in your drying environment does seem a little low. Try adding a humidifier and avoid direct exposure of the film to your heat source. Do you weight the ends of your film when drying? I have also had some luck with cutting my film into smaller sections before drying.

 

I hope this is of some help to you. I think we have all had this problem at some point in time.

 

Michael D. D'Avignon

Iunno m8. The <I>new </i> delta 400 in 35mm is a bitch too.

All films curl during drying for the simple reason that the gelatine

emulsion contracts (shrinks) as it dries, where as the acetate

base does not...the only solution is not to dry your film in a drying

cabinet or a warm room; the longer the film takes to dry the

less curl that occurs.

Incidentally, the longer the film takes to dry the less it will suffer

from drying marks and dust!

Thanks all, this gives me some ideas to try.

 

The Delta 100 (120) I did yesterday didn't curl, and I've got another

roll of Delta 100 (120) hanging up now. One of the EFKE rolls I tried, the 1st, curled so badly it had an O shape, far beyond the U that occurs sometimes...

 

If this works, the steam source in the closet, and one outside in the

room, I'll standardize on that. I guess I've been trying a lot of films recently, just to see what works best for me, and which of those I really like. The EFKE R50 has indeed a nice tonal quality to it, that and Maco IR 820c are pretty cool.

 

And yes, I always use a weighted film clip at the bottom of the film (and it's held at the top by one of those 3" wide binder clips)

 

Thanks! I'll likely sort this all out - it's been my only real technical problem for quite a while! Now if I could just get 120 film CONSISTENTLY lined up in my Mamiya 7, I'd be even 'happier'

Also PMK is a tanning developer which may cause the gelatin to shrink more than usual. Here we go again with the non=word wrap.

I don't know - I mean, you could be right, BUT, the film curled just as much developed in DD-X, and XTOL, as it did with PMK. However, I am still going to use it. It looks special.

 

The roll i ran through DD-X (1:28, 71 degrees, 55:00 developing time with 10 seconds of agitation every 10 minutes) looked really nice. Not too contrasty, or flat, nice looking sky - and that roll was shot with a modified Holga neamed Helga! Hm. I'll post a flatbed scan of the DD-X proofsheet (well, one of the images) as soon as I get it scanned, JUST IN CASE anyone runs across this thread and finds it useful, etc. etc.

<b>OK</b>

 

Here's a flatbed scan of a print. Details - printed on Luminos RC VC at grade 2, processed in Dektol for 60 seconds. Fixed and washed normally.

 

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