Hello all. I stumbled across this forum looking for F76+ 1:19 info, and I am amazed at the wealth of analog info. I'm pretty much learning all of this on my own- I scored a Ricoh KR-5 Super II on eBay when I really just wanted the lens for my digital body, but I put a roll of black and white film in it and fell in love.
I hope this hasn't been discussed to death (though a search didn't turn up anything). I've more or less been able to figure things out using the magic of the internet and massivedevchart, but one thing continues to bother me: I hang my negatives using weighted clips and run a film squeegee over them a few times, and while the weighted clip on the bottom keeps them drying straight, they are developing a side-to-side warping, maybe 1/4" in total depth once they're dry. Picture a PVC pipe cut in half the long way and you have the rough idea, while it isn't that extreme. A friend seems to have suggested that the squeegeeing may be doing this, but I feel like letting them dry just a bit curved from top to bottom would prevent the warping. Any thoughts? I'd really like to keep squeegeeing rather than having to add something like Photo Flo to the mix. Your help is greatly appreciated.
Firstly, most including I, will caution against squeegeeing film. I now just run my fingers along the film, after using a similar product to Photoflo. One too many scratches will make you decide against the squeegee, and if you squeegee without using Photoflo, you will almost certainly get more scratching. Several films are prone to warping, sometimes lengthwise and sometimes side to side like yours. After you cut them into strips and sleeve them, if you leave a couple of telephone books (remember them?) on top, you should cure most of the warping.
I'll second Kevin's comments, especially in light of the original comment about "...run[ning] a film squeegee over them a few times..." -- I cringed a bit at the words "a few times." If you feel you must squeegee, do it once to minimize the risk of scratches. I squeegeed when I first started doing B&W processing because "official" sources all seem to recommend it; but I stopped a while back after getting some suspicious scratches and I haven't started again.
As to the film curl, unless it's bad enough that you can't get the film into an enlarger or film scanner, I wouldn't worry about it. If it's bad enough to cause problems, consider changing the brand of film you're using. They do curl differently. Generally speaking, the bigger names (Kodak, Ilford, and Fuji) produce film that curls less than the smaller manufacturers (Foma, Efke, etc.). Some people seem to have more problems than others, though. Whether that's because some are more bothered by an objectively similar amount of curl than others or because of objective differences because of batch-to-batch variability, different drying conditions, etc., I don't know. I've noticed that film I've had for a while (frozen bargain film stored in my freezer for a couple of years, say) tends to curl more than fresher film.
I've got some half-baked theories:
1) the faster film dries (more air movement), the more it curls,
2) the greater the temperature differential between chemistry/rinse and the air temperature, the more it curls,
3) the thicker the film base, the more it curls,
4) the narrower the film format, the more it curls.
So why are my films no different when dried here in Turkey, it's 38°C at the moment, compared to when I'm in the UK and its 16°C
It just depends on the film base used,pure & simple.
Sponsored Ad. (Subscribers to APUG have the option to remove this ad.)
Maybe I missed something, but it has been my experience that 35mm flim does curl edgewise;
If it did not, the necessity for pressure during enlarging or conact printing would be much reduced.
It seems like the curl decreases after processing and storage in sleeves over time; some old negatives becoming quite flat.
Is it possible you are describing the normal expected curl?
Sheet film may be flat, but not my 35mm stuff....
Also, I do think curl can be manipulated by drying conditions; residual moisture level and stress during drying... depending upon the material.
I beg to differ, Ian. When I moved to Oslo from the UK, I found much more curl in any given film. The relative humidity here is very low compared to the UK, and keeping drying temperature, film type, etc, the same, it is the only variable left. Films dry here in a couple of hours whereas I used to leave them 5-6 hours back in sunny Surrey.
Originally Posted by Ian Grant
The heavy book treatment seems to work fairly well, though.
I don't know how there could be a conflict twixt Photo Flo
Originally Posted by luckycharms
AND squeegeeing. I used a sponge type for years and do not
recall any problem. I've now a small eight blade by Jobo that
works like a charm.
With water alone some difficulty is encountered. With the
film given a short soak in half strength Photo Flo and the
squeegee too, a single slow stroke does the job. Film
That Jobo by the way sells under other brand names.
I suspect there is a lot of knocking prior to trying
amoung those who rail against the use of a
Film squeegee. I wouldn't be without. Dan
If you had a relatively soft emulsion then squeegeeing could easily cause a major problem, such as described.
Originally Posted by dancqu
Certainly if you put a squeegee anywhere near EFKE films you'd have problems.
Try drying in higher humidity.
This is an APUG tip I found: wet the walls of a shower cabinet and hang the film to dry there, with door or curtain shut. I've found my films dry much flatter, with the prolonged drying time. This applies for 35mm and 120.
When drying more slowly, the Photo-Flo has a better chance to let the water run off, and I find no water spots. No squeegeeing for me.