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crazy
18-Jul-2006, 06:55
Out of frustration with lack of materials that I had been using as a hobbiest for years I shelved the med. format equipment and pulled out the big stuff. I figured that I might as well start mixing my own chem. as well, and became intriged with Pyro. I settled on Berrger bfp 200, 510 pyro and fixed in f-24 with water wash between, all at 66 degrees. I'm shooting this film at 200, and I don't have a desiometer.
Two questions really; I have settled on a dev. time of 11 min. but negs seem a little thin, but print well. Anyone have any experience with this combo?
Secondly, some of the sheets have tiny "pin holes" in the emulsion, Is this a bad box of film or could the fixer and its temp be causing the problem?

Thanks from a newbie

Jim Noel
18-Jul-2006, 08:20
Don't be concerned about the negatives appearing thin. If important shadow areas have sufficient detail in the print your exposureis sufficient. If the highlights are neither too flat, nor burnt out, your devlopment procedures are fine.

The appearance of the final print is the goal. My negatives may appear thinner, or more dense, more or less contrasty than yours, etc., but if we both get good prints, then both of us are correct in our exposure and processing.

Welcome to LF photography.
Jim

Jim Noel
18-Jul-2006, 08:22
I forgot to discuss pinholes.
If you are using an acid stop bath, go to plain water. Also be sure the temperatures of your chemistry are consistent.
These two steps should eliminate the pinholes.

Jay DeFehr
18-Jul-2006, 11:52
Hi Crazy.

These Forte films require more development than other films, and your process seems to be in line with what I would expect from that film/developer combination. As Jim noted, adequate shadow detail indicates proper exposure, and easy-printing highlights indicate proper development. Many users don't consider BPF/Forte 200 to be a true 200 speed film, or prefer more density in their negs, and so derate their film from EI 200 down to EI 160, or less, but thinner negs are sharper negs, so if you're getting good shadow detail, stick to what you're doing. I too get occasional pinholes in the emulsions of these Forte films, which I attribute to coating defects. There is nothing in your process, as described, that would cause pinholes, and if you try another film, I'm sure the problem will disappear.

If you're feeling adventurous, and have the eqipment to do so, you might consider trying some semi-stand development. With 510-Pyro, it's very easy to extrapolate a new development time for semi-stand based on your current time for the 1:100 dilution. To use the 1:500 dilution, multiply your 1:100 time by five, and add 25% for the reduced agitation, for a total time of 69 minutes. Agitate vigorously for the first minute, and then a few gentle inversions at the halfway point of development. This procedure enhances local contrast in the midtones, while retaining normal overall contrast for easy printing. The effect can be spectacular, and BPF/Forte 200 responds very well to this technique.

What format are you shooting, and how are you developing your negs? Aren't big negs cool? Enjoy.

Jay

crazy
19-Jul-2006, 06:19
Gentalmen, thank you for your reply.

To answer Jays questions, I'm shooting 4X5 from a Omega View (purchaced when I was in high school, 25+years ago) with a primary Schneider 210/370 lens. And I don't know that I'd call it large, I'm playing with my Graflex with sheet film, also with a couple of schneider lenses.
To come up with developing times, I was tray developing with constant agitation, and a couple of inspections, basicly to get some idea of desity. Once I settled on a time I loaded eight sheets into a Yankee adjustable "agitator" daylight tank, again using constant agitation. This was disappointing, as some sheets are under developed in the center area of the neg. the edges are as I expected, but in a rough rectangle in the center they are thin. Any ideas there?

Back to the pin holes. These are very irritating to me. I know of no way to repair either the neg or print. I have been using a water wash of about 1.5 minutes instead of a stop bath. Would changing to some other fix that is less temp. sensitive be an idea, and if so what might you suggest?

Thanks again, and yes, big negs are verry cool!!

Crazy

Michael Graves
19-Jul-2006, 07:51
Some films let you spot out pinholes on the negative, if there is some tooth to the surface. I've never been all too good at that. Freestyle sells this set of bleach pens for taking the black specks off the print. After a little practice on some prints i was going to throw away anyway, I sort of got the hang of using them. If you bleach too much, you can use spotting dye to even it out.

But the best way is to not get them. Jay's suggestion about the plain water bath instead of acid stop is important to follow. Once I stopped using acid stop, I noticed a significant decrease in pinholes. I reduced dust specks by vacuuming the film holders before I load them, dusting the film and holders with Dust Off during the loading process and storing the holders in antistatic zip lock bags from the moment they're loaded until the moment they're developed. (Except for while shooting, of course. The zip lock bags make funny patterns on the image if you don't take the film holders out before exposing them.)

Jay DeFehr
19-Jul-2006, 10:18
Hi Crazy.

Given the choice between trays and a Yankee tank, I'd stick with the trays. Agitation in the Yankee tanks is problematic, and uneven development is typical. You might consider picking up a Jobo 2521 tank and 2509n reel. This outfit will allow you to process your 2x3 and 4x5 negs 6 at a time, with your choice of agitation schemes, and very even development.

michael makes a very good point about dust; not all pinholes are emulsion defects. Any small particles on your film during exposure will show up as pinholes when developed. Your fix is fine, and not the cause of your pinholes.

What kind of Graflex are you shooting?

Jay

crazy
19-Jul-2006, 20:47
I never even thought of latent dust on film holders. A brand new source for my paranoia.

Jay, I thought that the Jobo 2500 series were to be used with a prosseser (not in the budget). Can one use them like a inversion tank? I also noted that Jobo make a roller base (non-motorized), would this be the way to go? Why I bet a clever chap with some tinkering skills might just motorize that base.

My Graflex is a Century Graphic with a 100mm F3.5 Zeiss Tessar lens, I also have mounted on another lens board a Schneider Tele-Xenar 180mm f5.5. I have two roll film backs,one 2 1/4 X 2 1/4 the other is 3 1/4 X 2 1/4 . I don't ever remember using either of them, sort of a ground glass/sheet film kind of guy, not to mention, I have several other cameras that can only shoot roll film.

Thanks for all the info guys!!

Crazy

Jay DeFehr
19-Jul-2006, 21:34
Crazy,

a clever chap just might. The magnet base makes coupling a simple proposition, and a reversing motor with a bent shaft could provide random agitation. The 2500 tanks can be used for intermittent agitation, but require more solution to do so.

I love those old Graphic cameras. I have a 4x5 Crown Graphic with a 135 Schneider Xenar, and an old 3x4 Graflex RB SLR with a 150 Xenar. I'm loving the RB, and haven't given the Crown much exercise lately. Some say that 3x4 is too small for contact prints, but I'm having a lot of fun making them. Enjoy.

Jay