Efke 25 problems.

[j.e.simmons]

I've used Efke films for several years and they both have special qualities and are prone to scratching. I've found the safest way to develop is one at a time - either in a tray with a brush, or with a minimal agitation scheme in a tube (ala Steve Sherman) or in BTZS tubes as Brian suggests. I developed Tri-X, FP4 and HP5 by the shuffle method for 20-years without scratching problems, but I've never been able to reliably develop Efke films with that method.
juan

[KOG]

1. ...Are there special tonalities it gves you that make the difficulty seem worth the trouble? ...

steve simmons

Yes, there are special tonalities. After getting mediocre results while photographing my local Palo Duro State Park (Canyon, TX) using TMAX films, I thought that ortho films would give me more seperation between the red and yellow colored strata in the canyon.

After doing some research, I discovered that Efke 25 and 50 have less red sensitivity than other B&W films. Instead of Efke 25, I tried Efke 50 due to it's similar spectral profile and faster speed.

Using 35mm in a direct comparison between: Efke 50, Efke 100, Fomapan 100, Ilford FP4+, and Fomapan 200, I found that Efke 50 did indeed show more tonal seperation between the reds and yellows in the canyon. In addition, Efke 100 did not have better seperation, which seems to follow the more panchromatic spectral profile published for the 100 film. It is interesting to note that Fomapan 200 also showed better seperation in the reds and yellows[Edit: I do not expect this in sheet film as it has more red sensitivity]. All other B&W films I've used in the canyon look dull and muddied.

While my test was not exhaustive, I feel that Efke 25/50 do have enough merit to put up with any special care needed in processing. But, by using hangers and tubes, I have yet to experience any processing issues.

Kevin

[Brian C. Miller]

KOG, did you try green and blue filters before trying ortho?

[KOG]

KOG, did you try green and blue filters before trying ortho?

I have not tried true ortho films yet. I believe Efke 25/50 are billed as ortho-panchromatic, not quite a true orthochromatic emulsion.

During my tests I did shoot the same scence without filters, and then with yellow, green, and then polarizer filters (red was skipped because I didn't want the red soils to go lighter). I have not printed all the film and filter combinations, so I don't want to make any further comments at this time.

My goal in testing was to find a film that gave better results without filtration, so that I could use higher shutter speeds to compensate for the wind speeds the Texas Panhandle usually gets.

Kevin.