View Full Version : PMK and FP4+ Film Speed

Jerry Flynn
13-Sep-2004, 10:57
I have been experimenting with FP4+ in PMK. I am using trays and developing 10 min @ 70 degrees F.

The results have been interesting - I like the tonality. The mid- and high tones look fine, but shadows were thin. I have progressively reduced my E.I. and currently have been using E.I. 50, but the shadows are still a bit thin. I could keep increasing exposure and cut the development some, but it seems that having to shoot an ISO 125 film at E.I. 25 (which is where I think I would go next) seems like a high price to pay for greater sharpness and better highlight separation.

My approach is subjective -- I have a B&W densitometer, but I'm more interested in what happens with actual pictures of actual subjects.

Does anyone have specific experience with this combination? I'd be interested in what you have found to be a proper speed.


Andre Noble
13-Sep-2004, 11:05
I also found FP4+ at around ASA 40 in another pryo, Wimberly WD2D+. It took that 'low' ASA to get the shadow details right, but the highlight tonality still remained superb at the 40 ASA mark.

In same pyro developer, I found Agfa APX 100 to be at ASA 32 or even ASA 25.

steve simmons
13-Sep-2004, 11:39
Have you tried printing them.? If not that is the real test.

steve simmons

Jerry Flynn
13-Sep-2004, 12:34

Thanks for pointing out the omission in my original post. I have, indeed, printed them. I knew a visual inspection of a stained image could be misleading.

What should be a Zone III comes out in the print looking like a dark Zone II (thus my guess at E.I. 25). Holding back the area just results does not improve detail; it just looks weak.

steve simmons
13-Sep-2004, 13:34
I use zone 3 for deep tones but good texture and detail. Zone 2 is too deep for much detail in my system.

I get an EI of 100 wth PMK and FP4+.

steve simmons

Gary Samson
13-Sep-2004, 19:25
I have used FP4+ with Pyro PMK for many years (4x5 and 8x10 sheet film as well as 120 roll) and my exposure index for this combination is 100. I am using the Jobo Expert drums on a Jobo processor and I continue to use the afterbath even though it is generally not reccommended any more. I have reduce the EI only when I am making long exposure photogaphs of interior scenes where reciprocity kicks in.

CP Goerz
14-Sep-2004, 00:56
Just curious, is your lightmeter working OK? I manage to get 125 with similar development times/temps etc. Have you tried other films in PMK etc before trying FP4? If so did you also notice a big drop in speed?

CP Goerz

Tim Curry
14-Sep-2004, 06:47
Typically with PMK the film speed drops, but not as much as you have mentioned. I second looking into your light meter and system. If you drop below iso 64 there may be a light meter issue, weak developer, bad shutter or some other glitch in the system.

Are you using distilled water or tap water for mixing your chemistry?

Do you have access to another meter or camera to compare readings and take comparison shots?

Can you use a step wedge to see what is actually happening in a single shot to check densities?

ISO 25 seems very slow with PMK, there must be something else happening.

Jerry Flynn
14-Sep-2004, 07:59
Thanks, all, for the responses.

I belive my meter is OK, since the readings it is giving me are reasonable -- within "sunny 16" and past experience based on the E.I. I set on the meter. The samples I shot were with various lenses/shutters and results were the same.

The responses you have sent stating that the film speed should not be that low have confirmed my suspicions that something was not right.

I did use distilled water in mixing the kit, but I think a new batch of developer is in order. I have ordered pre-mixed from Photographer's Formulary in order to rule out user error in the mixing process.

Thanks, all.

Kirk Keyes
14-Sep-2004, 11:30
I just did some development tests this weekend on PMK and FP4+. I got an EI of 50 at a CI of 0.57 using the visual channel on my densitometer. Using the blue channel, I got a CI of around 0.65 (I think) and an EI of 64 on the same piece of film.

You said you have a B&W densitometer, did you use it for these tests? A B&W densitometer will not be able to efficiently measure the yellow stain in the film as well as one that can measure the blue only.

By the way, I also ran some Acros and got an EI of around 80, which is much closer to it's nominal speed of 100.

Tim Curry
14-Sep-2004, 12:25
Are you using distilled water to maix the working solution?

John C Murphy
14-Sep-2004, 13:06
I don't see where anyone has mentioned the agitation issue with pyro. Which one are you using, the Hutching's 2 shakes every 15 seconds method or the Anchell and Troop continuous agitation technique? Regardless, make sure you are agitating sufficiently. Hope this helps.