David Lyga
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There is much wonder out there by some as to how long to develop a certain film in a certain developer. I have adopted a way to develop ALL B&W film for the SAME TIME in any given developer by using varying dilutions. I will talk about five basic films and you can interpolate others that are similar to these five groupings (like substituting HP5+ for Tri-X).
First, when I say 'dev %' I mean a certain percentage of your stock solution in a working solution. For example, if I say "33%" I mean one part dev stock and two parts water, giving a working solution containing 33% developer. Or, a "20%" would mean one part dev stock plus four parts water, giving a WS containing 20% dev.
Figure a minimum of 6 ml working solution for each 35mm frame and include the leader in your frame count. Thus, a 36 exp roll would be '40 frames' and would need a minimum working solution of 240 ml ( 6ml X 40 frames ). A 24 exp roll would really be '28 frames' and would need a working solution of 168 ml. (Fewer frames get proportionately less working solution.) I regularly cut off film from the camera rather than force myself to use up the whole roll and use smaller reels (I painstakingly have cut them smaller) and smaller water tight containers (approximately conforming to the smaller reel size) to hold these smaller lengths efficiently).
I agitate by keeping the water-tight tank on its side and continuously turning it during processing (in a tempered water bath) so it is not necessary to have the solution cover all the film at the same time. Perhaps the water bath for B&W might not even be necessary (but I conform to this WB procedure because I also process color negative film at 100 F). Rolling it this way guarantees even development: (The reel is being continuously rotated (maybe one full turn takes about 10 seconds) like a Ferris wheel turns, in one direction.) Personally, I like an ambient temp of 80 F and have NEVER had a problem with this. (Even up to 90 F is OK if all subsequent solutions are at a like temp and EVEN with the old technology films.) Find a temp and a developer you feel comfortable with and keep those data consistent.
Here are the developer percentages I have found to give equivalent contrasts (gamma) with various films I use. I like good shadow detail so I do expose more than most do.
100% with T Max 3200 (rate at EI 500) (for some reason this film demands more development than similar super fast films).
60%: generally the ISO 400 group, including T Max 400 (rate these at EI 250) but also includes the Ilford 3200 (rate at EI 800) and Fuji 1600 (also rate at EI 800).
40%: generally the ISO 100-125 group, including T Max 100 (rate these at EI 64)
30%: Pan F+ and discontinued Kodak Panatomic-X (rate these at EI 16)
25%: discontinued Kodak Technical Pan (also rate at EI 16)
20%: Kodak Imagelink HG Microfilm (rate at EI 4). This film is not perforated so creative ways are going to have to be employed to run this through a normal 35mm camera. I load the film (in the dark) onto the take-up spool (emulsion side down but NOT taped to it, tedious!) and anchor, with tape, the end onto an empty rewind spool that I place into the rewind compartment of the camera. I 'advance' film by turning the rewind crank about 360 degrees to pull the film onto it. The sprockets simply glide over the film and cause no trouble or damage. This film has a very low exposure latitude so don't expect to see that black cat in a coal bin and ALSO, in the same frame, see the detail in a white, sunlit church. Either expose only in low contrast situations (to get a full tonal rendition) or expect to loose much of both the highlights and shadows in contrasty situations. Obviously, changing the EI will maximize the detail with either the shadows or highlights (at the expense of the other).
The development time you will have to ascertain for your own particular developer by clip testing a small piece of one of the aforementioned films at its respective developer dilution. When you do get a proper negative for THAT time, the other films should be OK at the SAME times using their respective developer dilutions. Tweak the percentages if necessary but I doubt if you will have to do that. Of course, if you change developers you will, again, have to determine a proper time for that particular developer, but the percentage will always remain the same. You can speed up developer energy by putting maybe 2g of sodium carbonate per liter of dev STOCK. You can slow down developer by putting maybe 4g of baking soda (sodium carbonate) per liter of dev STOCK. You can MAKE sodium carbonate by putting a little baking soda in a pan and heating it until the air bubbles stop forming (about 3 minutes of intense heat). CAVEAT: the pan gets HOTTER than if boiling water so be VERY careful. Also, do not use more than an ounce or two of baking soda at a time as it might get a bit messy on your stove. - David Lyga
First, when I say 'dev %' I mean a certain percentage of your stock solution in a working solution. For example, if I say "33%" I mean one part dev stock and two parts water, giving a working solution containing 33% developer. Or, a "20%" would mean one part dev stock plus four parts water, giving a WS containing 20% dev.
Figure a minimum of 6 ml working solution for each 35mm frame and include the leader in your frame count. Thus, a 36 exp roll would be '40 frames' and would need a minimum working solution of 240 ml ( 6ml X 40 frames ). A 24 exp roll would really be '28 frames' and would need a working solution of 168 ml. (Fewer frames get proportionately less working solution.) I regularly cut off film from the camera rather than force myself to use up the whole roll and use smaller reels (I painstakingly have cut them smaller) and smaller water tight containers (approximately conforming to the smaller reel size) to hold these smaller lengths efficiently).
I agitate by keeping the water-tight tank on its side and continuously turning it during processing (in a tempered water bath) so it is not necessary to have the solution cover all the film at the same time. Perhaps the water bath for B&W might not even be necessary (but I conform to this WB procedure because I also process color negative film at 100 F). Rolling it this way guarantees even development: (The reel is being continuously rotated (maybe one full turn takes about 10 seconds) like a Ferris wheel turns, in one direction.) Personally, I like an ambient temp of 80 F and have NEVER had a problem with this. (Even up to 90 F is OK if all subsequent solutions are at a like temp and EVEN with the old technology films.) Find a temp and a developer you feel comfortable with and keep those data consistent.
Here are the developer percentages I have found to give equivalent contrasts (gamma) with various films I use. I like good shadow detail so I do expose more than most do.
100% with T Max 3200 (rate at EI 500) (for some reason this film demands more development than similar super fast films).
60%: generally the ISO 400 group, including T Max 400 (rate these at EI 250) but also includes the Ilford 3200 (rate at EI 800) and Fuji 1600 (also rate at EI 800).
40%: generally the ISO 100-125 group, including T Max 100 (rate these at EI 64)
30%: Pan F+ and discontinued Kodak Panatomic-X (rate these at EI 16)
25%: discontinued Kodak Technical Pan (also rate at EI 16)
20%: Kodak Imagelink HG Microfilm (rate at EI 4). This film is not perforated so creative ways are going to have to be employed to run this through a normal 35mm camera. I load the film (in the dark) onto the take-up spool (emulsion side down but NOT taped to it, tedious!) and anchor, with tape, the end onto an empty rewind spool that I place into the rewind compartment of the camera. I 'advance' film by turning the rewind crank about 360 degrees to pull the film onto it. The sprockets simply glide over the film and cause no trouble or damage. This film has a very low exposure latitude so don't expect to see that black cat in a coal bin and ALSO, in the same frame, see the detail in a white, sunlit church. Either expose only in low contrast situations (to get a full tonal rendition) or expect to loose much of both the highlights and shadows in contrasty situations. Obviously, changing the EI will maximize the detail with either the shadows or highlights (at the expense of the other).
The development time you will have to ascertain for your own particular developer by clip testing a small piece of one of the aforementioned films at its respective developer dilution. When you do get a proper negative for THAT time, the other films should be OK at the SAME times using their respective developer dilutions. Tweak the percentages if necessary but I doubt if you will have to do that. Of course, if you change developers you will, again, have to determine a proper time for that particular developer, but the percentage will always remain the same. You can speed up developer energy by putting maybe 2g of sodium carbonate per liter of dev STOCK. You can slow down developer by putting maybe 4g of baking soda (sodium carbonate) per liter of dev STOCK. You can MAKE sodium carbonate by putting a little baking soda in a pan and heating it until the air bubbles stop forming (about 3 minutes of intense heat). CAVEAT: the pan gets HOTTER than if boiling water so be VERY careful. Also, do not use more than an ounce or two of baking soda at a time as it might get a bit messy on your stove. - David Lyga
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