Slow Film (around 25 ASA) Recommendations

I'm interested in trying some super slow film, I'm after some recommendations and opinions, as I havn't used film this slow before, nor have I tried any of the brands selling it. There's a 25 and a 20 from Adox, though I'm not sure what the difference is, Rollei Pan 25, and probobly many others.

I generally use Tri X 400, not necessarily after the same look, but this is where I'm coming from.

Thanks,
Geoff

In general these films fall into 2 categories:

The range of films with higher resolution and normal contrast which are quite uncritical about the developer.

The range of films with ultra-high resolultion and high-contrast. These need special, sometimes even proprietory, developers to to gain normal contrast, an acceptable speed and being free of developing artefacts. Some of these films were not even designed for pictorial use.

With your hint at Adox you have mentioned films of both groups.

Efke makes both a 25 ISO and a 50 ISO in "standard-type" films. I know nothing about other films they make.

Ilford makes Pan-F with an ISO of 50.

I you are processing yourself, you could shoot a 100-125 speed film and run it thru Microdol-X or a PPD dev and loose 1 stop in speed. That would get you to a speed of 50-64.

The Adox/EFKE KB/R/Pl 25 is an excellent film I've used it in all formats from 35mm through to 10x8. Very sharp, extremely fine grain and good tonality.

Ian

Adox CMS 20 is the sharpest, finest grain B/W film liek evarrr.
Adox CHS 25 is a 25 ISO speed film.

I'd try Ilford Pan F (ISO 50). You can expose this film at EI 25 with no change in development required (though you might like the way it looks if you take off 10% or so). If you want it to be even lower in contrast (and IMO "normal" looking), try it at EI 12 and cut about 30% from the development. Efke/Adox are nice, but Pan F is available in any good photo shop, there is plenty of information available for it, and it does not require anything different than what you are doing to develop Tri-X. In my experience, the Efke/Adox films are gorgeous, but are a little more fragile, finicky, and harder to nail down. It seems to me that most people, myself included, find the recommended times to need notable tweaking, for one thing. A hardening fixer is recommended, so that should be procured (if you are not already using one with your Tri-X), and there is not the plethora of information available for them as there is with Pan F. The Pan F will let you know if slow films are something you can use, then you can put the work into Efke/Adox if you want to keep using slow films. They are certainly worth it, but I would not recommend them as a first trial run into the world of slow films.

The adox CMS 20 is a microfilm of ASA 8 or so. You need a low contrast developer.

Yes, the microfilms have a very slow speed.

Let's concentrate on the iso 25 film:

Rollei Pan 25 (a modified NP15 (OrWo) emulsion.)
Rollei Ortho 25 (an orthochromatic emulsion)
Rollei ATP1.1 , an advanced Tech Pan film (iso 32)
Efke 25, a single layer iso 25 Orthopanchromatic film.

The Ortho 25 and ATP1.1 you can best development in a low contrast document developer (e.g. Rollei Low Contrast RLC). To use the ATP1.1 on high speed (iso 32-40) you need the dedicated ATP-DC developer.

Efke 25 and Rollei Pan 25 you can best develop in a 1+50 Rodinal or 1+1+10 high Definition Beutler developer.

I"ve used the Rollei Retro 25 film, described above.

It works very well, beautifully even, in Rodinal 1:50. It's not hard to find, given that even I can get it out here in the colonies.

Not sure what your ultimate aim is, but if you want long exposures, you can use this film (or similar ISO films) with neutral density filters...just a thought.

Adox CMS 20 can be shot at ISO 20 if you use the special Adotech developer.

2F/2F said:

I'd try Ilford Pan F (ISO 50). You can expose this film at EI 25 with no change in development required (though you might like the way it looks if you take off 10% or so).

Click to expand...

I have often used Pan F+ at 25 ISO for a beautiful creamy look, especially if developed in Perceptol which is a contrast sapping developer, so it requires a bit more development than Ilford recommends, IMHO. However, Ilford recommends decreasing development times about 25% when going from the 50 ISO rating to the 25 ISO rating (there is a table with recommended developing times on their site). I generally expose at 1/3 of a stop lower and develop as recommended to give a grain-free normal contrast development.

Developing Pan F+ in ID-11 gives a bit more contrast and accutance but at the expense of more grain. That said, there is such little grain to begin with, on my 6x7, I need to print at 12x16 to start to see the grain with the naked eye.

I've had excellent results from the Rollei and Adox Ortho 25 films developed in Rodinal at 1:100 for 1 hour with minimal agitation (but actually this has become my standard processing method for most b & w films and I've had equally good results from putting Tri-X in the same tank at the same time as the Ortho 25's). I've also tried the Adox CMS (?) 20 at Iso 25 in the Adotech developer which came out very nicely as well. They're very interesting films to use and not particularly difficult to get good results in 35mm format with prime lenses.

If you are shooting sheet film, try lith film. I shoot it at iso 5 and soup it in rodinal at 1+150 with minimal agitation for about 8 min.. You can develop it under a red safelight