Rikard
Established
Yes, also @Freakscene mentioned that he uses 18C. That's the magic number it seems. Any idea how much to adjust development time in % when moving from 20C to 18C?
Freakscene
Obscure member
Rikard
Established
Great! I also found a table from Ilford.
Godfrey
somewhat colored
Being an empiricist (and using the Rondix 35 or Rondinax 35 tanks, which essentially assert continuous agitation ...) essentially I have simplified my processing methodology down to almost nothing: Whenever I try a new film, I buy a couple of short rolls (20-24 exposure) and shoot a test (a nice, continuous toned print + a 20 step white to black chart + a color wheel, each in its own framed setup and with regulated lighting and incident exposure reading) with the taking exposure varied in half-steps from -1.5EV to +1.5EV from the nominal meter reading. I shoot two rolls of film this way.
I then process one roll in my standard developer (HC-110 diluted 1:49) for 8 minutes @ starting temp of 68°F. The goal is to see whether the "0" or meter measurement point is in the center of the sequence or on the minus or plus side, density-wise. Once processed, I scan and look at the exposures in LR Classic, using its tools to tell me where the center point in the ranges might be.
If they're all on center, I'm done after the first test roll processing. If they're off a half-step or two, I make an estimated guess at how much time to add or subtract from my nominal 8 minute process time (based on my experience...) and process the second one. I'm usually right on the money with the second test roll due to long experience with this developer and processing methodology.
After that, I don't worry too much about it.
The biggest variation I've run into doing this in recent years has been processing Ferrania P30. Their spec says ISO 80 and elects a developer that is hard to find in the USA. I've found that if I rate it at ISO 32, increase dilution of HC-110 to 1:99, and double the developing time, I get near perfect negatives. The usual variations I've found are usually to increase or decrease the processing time by 1 minute (Ferrania P33 rated at nominal ISO 160 wants an extra minute processing time; Ilford HP5 rated at 400 as well), and Ilford Delta 400 seems to want about 10 minutes processing time. Etc.
I only shoot B&W on film nowadays, and I try to keep the film processing as simple as possible. The cost of buying and processing two test rolls is fairly trivial; I've only used HC-110 for the past 20-some years. But I'm becoming intrigued to experiment with Rodinal again ... I like the grain structure I'm seeing in some of your test photos!
G
I then process one roll in my standard developer (HC-110 diluted 1:49) for 8 minutes @ starting temp of 68°F. The goal is to see whether the "0" or meter measurement point is in the center of the sequence or on the minus or plus side, density-wise. Once processed, I scan and look at the exposures in LR Classic, using its tools to tell me where the center point in the ranges might be.
If they're all on center, I'm done after the first test roll processing. If they're off a half-step or two, I make an estimated guess at how much time to add or subtract from my nominal 8 minute process time (based on my experience...) and process the second one. I'm usually right on the money with the second test roll due to long experience with this developer and processing methodology.
After that, I don't worry too much about it.
The biggest variation I've run into doing this in recent years has been processing Ferrania P30. Their spec says ISO 80 and elects a developer that is hard to find in the USA. I've found that if I rate it at ISO 32, increase dilution of HC-110 to 1:99, and double the developing time, I get near perfect negatives. The usual variations I've found are usually to increase or decrease the processing time by 1 minute (Ferrania P33 rated at nominal ISO 160 wants an extra minute processing time; Ilford HP5 rated at 400 as well), and Ilford Delta 400 seems to want about 10 minutes processing time. Etc.
I only shoot B&W on film nowadays, and I try to keep the film processing as simple as possible. The cost of buying and processing two test rolls is fairly trivial; I've only used HC-110 for the past 20-some years. But I'm becoming intrigued to experiment with Rodinal again ... I like the grain structure I'm seeing in some of your test photos!
G
Freakscene
Obscure member
Agfa used a target CI of 0.65 for all its film development times, which is way, way higher than normal. But it also makes the films look faster than they are. I have no idea why they did this, except that maybe someone at Agfa just liked high contrast, and marketing APX100 as APX80 or 64 maybe didn’t appeal as much.
Rikard
Established
@Godfrey you are a better scientist than I am
My next test was Rodinal at 18C, but 1+25 with agitation every third minute. I did 12:15 minutes. A bit too long. So low contrast stuff comes out good and high contrast shots are too contrasty. But it was fairly alright anyway. There is grain of course
Pictures unadjusted from scanner.
My next test was Rodinal at 18C, but 1+25 with agitation every third minute. I did 12:15 minutes. A bit too long. So low contrast stuff comes out good and high contrast shots are too contrasty. But it was fairly alright anyway. There is grain of course
Pictures unadjusted from scanner.
Rikard
Established
Another test Tri-X @320. Rodinal 1+75, 20C, 15 minutes. Pretty sharp images. Can handle high contrast scenes ok. Better would be 14min though.
Rikard
Established
Just an update. I have settled on 18min, 19C, 1+50 with gentle agitation every 3rd minute. One important thing is to make sure that the temp of stop and fix is pretty spot on as well. A few degrees off and the grain can become noticeable less nice.
Here's one high contrast scene from the last roll. Still high contrast but it's what I like.
Here's one high contrast scene from the last roll. Still high contrast but it's what I like.