View Full Version : FP4+ in Rodinal

29-Jul-2004, 08:21
What characteristic differences will it make if one were to develop FP4+ in Rodinal 1:25, 1:50, and 1:100? How much development time (in %) should one reduce if changes in dilution from 1:100 to 1:50, and 1:100 to 1:25 is desired? Thanks!

Bob Fowler
29-Jul-2004, 09:01
For starting development times, see: http://www.digitaltruth.com/devchart.html

I like it at 1:50 myself.

ronald lamarsh
29-Jul-2004, 09:47
The major reason to increase dilution is to change contrast range or "gamma" of the image. So if you meter an image that has 7 stops between the low and high readings you'll get an easier to print negative by using 50:1 or 100:1. Keep in mind this all works to a point as you can compensate only so much before you loose midtone contrast which will really make a flat looking print. All said I really like rodinal, I use PMK also, but use rodinal for low contrast scenes and alt process negatives as it is much easier to do plus dev with it. Search the web I read somewhere that someone was using 150:1 and 200:1 for extreme compensating developement.

John Cook
29-Jul-2004, 12:19
Exact development times differ for each photographer, as do his working methods, lab water quality and equipment calibration. But generally speaking, 1 to 25 dilution will require slightly fewer than ten minutes. While 1 to 100 will need slightly under twenty minutes. Any closer than that will require testing on your part.

Increased dilution tends to yield slightly greater apparent sharpness, which makes the grain slightly more apparent. As you approach the (weak) limits of dilution, compensation begins to reduce negative contrast. I believe the factory recommends 10ml per roll or per 8x10 sheet as the minimum safe amount of developer.

Less developer works for some photographers, but below 10ml per roll you will be entering the land of unpredictable results. When diluting, it is better to add additional water than to withhold developer. For example, do a one liter Nikor tank with only one roll of film (and one empty reel), 10ml Rodinal and 990ml water. A 500ml tank with only 5ml of developer can be dangerous.

I have not tried this combination on FP4 Plus, but on films I have extensively tested, 4x5 film enlarged onto 11x14 paper shows hardly any difference with different dilutions. This sort of thing really requires 35mm Tri-X blown up to 16x20 before you get remarkable (artsy) results.

Richard Boulware
29-Jul-2004, 12:56
Just... an aside....about Rodinal. Many photographers on this board seem to be omiting one of the fine characteristics of Rodinal.

Rodinal is one of those developers, when diluted, will continue to work on the shadows, and self exhaust on the highlights, when used properly. When using continuous agitation, this effect is minimized or lost when using continuous agitation, like rotary developing system that use continuous agitation, like JOBO.

Compare the old dip-n-dunk system, with minimal agitation, and you just might be surprised on the tonal scale you will find, with minimal agitation.

Walter Glover
29-Jul-2004, 17:02
I am a stalwart of Phil Davis's BTZS calibration methods. Recently I did FP4+ in Rodinal at 1+25, 1+50, 1+75 and 1+100.

Grain I can't comment on because I was using 8x10 with a view to contact printing. Similarly, changes in acutance were also difficult to assess. I found very little, if any, tonal difference between images shot at the calibrated ratings and processed for the calibrated times. What I did find was a reference to Agfa's oft-stated claim that variation in scene brightness ranges can be compensated by variation of dilution.

At 1+100 I could do a lot of contraction but to even expand to N+1 would take forever. as the solution got stronger I found I could easily achieve different levels of expansion and contraction until I got to 1+25 where any contraction would result in foolishly short dev times.

Another thing to consider is to purchase the smaller bottles of concentrate unless you are going to do a big batch of film in super-quick time since the liquid oxidises quickly even in a stoppered bottle once it has been opened. It is no where near as economical but the consistency is worth the cost. I used to like the little rubber stoppers in the old glass bottles because I could pierce the top with a syringe and withdraw my Rodinal medicine with minimal entry of air.

My tests were tray developed at 72 with constant agitation for 1st 30 seconds and then 5 seconds each minute thereafter.

As a guide here are my results aimed at Ilford filter #2. Use these results as an indication of the variation but do not take them as gospel without doing a test of your own first:

1+100 = 13:28

1+75 = 11:26

1+50 = 7:00

1+25 = 5:06

The EI remained 100 throughout.


J. P. Mose
30-Jul-2004, 10:51
I agree with Richard. I use a JOBO 2500 tank for developing 4x5 sheet film. However, with Rodinal (at 1:50) I fill up the tank and use the inversion method for agitation since the is a compensating developer. I only agitate 5 seconds every 60 seconds. Yes....this is a lot of liquid....but Rodinal is so inexpensive that it doesn't matter. After development, I finish the process (stop bath, fixer, hypo clear) with the rotation method which uses considerably less volume. I also use distilled water with Rodinal.

I think Rodinal is spectacular with T-MAX 100, Technical Pan and FP4. In fact, I almost walked away from T-MAX 100 until tried Rodinal (I think it was Richard Boulware and Rick Nordin that got me started on this).

30-Jul-2004, 19:16
Thank you all so much for the infomation. They are very helpful to me. Lots of things I didn't know before. Special thanks to Walter for sharing your calibration test info. They provide very good starting points for me. Thanks!

Hans Berkhout
30-Jul-2004, 19:37
Page 19, Leica Fotgrafie Jan 1956: Interior of Reims Cathedral, good detail visible in shadows and rosette windows. Agfa Isopan FF in Rodinal 1:100, 20 Degr, 14 minutes. Little agitation; one inversion per minute. Cost less than 10 cents/film.