Black and White Film Testing in Diafine — updated for 2018
This is a collection of my film tests to date. As I test additional films, I will add them here. As of 2018, the films available continues to evolve, meaning that one-time favourites are no longer available (Fuji Acros 100) and new films are coming on the market (Ferrania P30.)
Every black and white film has it’s own unique look. This can be influenced by processing methodology. For these tests (where possible) I have standardized on developing in Diafine. This two-part developer is renowned for being forgiving of variances in temperature and processing time, as it simply develops to exhaustion. The results are repeatable. It also is amazingly long-lived and reusable.
Bracketed tests
My primary methodology of testing was to make a range of exposures, bracketed around the listed ISO speed from the film manufacturer (“box speed.”) Diafine typically gives a speed boost to traditional-grain films, which is reflected in my testing. Newer “cubic” style emulsions show less speed gain. By seeing the bracketed exposures together, it is easier to evaluate the tonality of each film and the exposure latitude the film has when developed in Diafine.
Scans were made variously by commercial labs running Noritsu scanners, or by myself (using Minolta Dimage Scan Multi III or Epson V500 scanners.) Scans were made flat, and the images had their levels adjusted for a consistent white point across all images.
Please refer to the image grids below for my results and to make direct comparisons between films.
Anecdotal updates — My current favourite films in Diafine
Since conducting my initial rounds of testing, I have continued to explore different films. I have relied on the experience of other photographers who have suggested effective ISO ratings for these films in Diafine, and I have been very happy with the results when following these recommendations.
For high-ISO needs, the combination of Diafine and Kodak Tri-X 400 is often recommended. After finally trying this classic pairing, I can confirm that Diafine and Tri-X work very well together, and the combination gives good results with a solid boost to the effective ISO of the film. It is also a very forgiving combination. It’s no surprise that the combination of Diafine and Tri-X was standard practise for many news photographers, as the results are predictable, flexible, and can produced under less-than-ideal processing circumstances. In my experience this combination gives slightly less grainy results than Ilford HP5+, with slightly higher effective ISO, and maintains moderate contrast that is easy to scan or print.
In my search for the perfect moderate-speed film, I finally tried Fuji Acros 100. I have heard many fine art photographers praise the smooth, grain-free images and tonality of Acros, and it also has a peculiarly good resistance to reciprocity failure (where required exposure times begin to grow longer and longer than the metered time would otherwise indicate if you try and expose the film for longer than a second.) As a modern cubic-style emulsion, I wasn’t sure what to expect with Acros in Diafine. I exposed it at a moderate ISO 160 (just slightly faster than box speed.) The results were exactly to my liking — good shadow detail, preserved highlights with just a bit of sparkle, and lots of mid-tone detail and micro-contrast. I adopted Fuji Acros 100 as my standard black and white film.
Unfortunately, Fuji has now discontinued Acros 100. This left me looking for a suitable replacement. Admittedly, I also hoped to find a film that would continue to be manufactured far into the future.
This search led me to Ilford, who already survived the collapse of consumer film and re-emerged completely dedicated to serving the dedicated film lover and fine art market. I sampled the moderate-speed FP4+. This traditional-grain ISO 125 film was originally a competitor to Kodak’s Plus X. It now finds itself having outlasted Plus X (as well as Fuji’s Acros).
As expected, FP4+ in Diafine yields a decent increase in speed. I am very happy with FP4+ exposed at ISO 250, which gives very little grain, and moderate overall contrast. There may be slightly less detail than Acros offered, but the overall impression is similar. I may actually prefer FP4+ for the way it handles highlights. Thankfully, FP4+ should be around for a very long time.
Summary of findings
The summary of test findings has been updated to include both the bracketed tests and my anecdotal testing.
