How much should I increase development time to increase contrast?

[Pylon757]

Hi, newbie to film.

I shot a roll of FP4+ recently and pretty much all the shots on it were shot in flat lighting, so I'd like to bump up contrast on the negs during development. The problem is I don't know where to start and for how long to increase development.

I'm using D76 1+1 by the way.

Many thanks,
James

 

[Anscojohn]

Were the film mine; and had I not made tests beforehand, I would increase time 20 %. Of course, just the next grade up paper than your norm would probably give all the snap you need.

 

[Mike1234]

What time/temp and how are you agitating? Does development look even?

 

[fschifano]

Ultimately, it will depend upon how much more contrast you're looking for, but 20% more is a good place to start.

 

[fschifano]

Ultimately, it will depend upon how much more contrast you're looking for, but 20% more is a good place to start. You could also increase the development temperature by a couple of degrees F and get to approximately the same result with your original development time. I'd prefer to vary the time rather than the temperature, but you may feel differently.

 

[Pylon757]

Thanks you guys, looks like I'll try the 20% increase, or around 13 minutes and 12 seconds with D76.

 

[Colin Corneau]

I normally process my negs 20% more as a standard, as I much prefer how it all looks. This is good advice.

 

[Mike Wilde]

The old Kodak b&w darkroom dataguide (I just got my 1977 edition a week or so ago) has great information about adjusting developer recommended times. There are factors for if you are processing in a small tank, large tank, if the film is a short or long toe, to account for the amount of flare that was in the imaging system taking the shot, and the number of stops of contrast that the lit scene had.

These adjustment factirs feed into a dial calculator, that is worth its weight in gold, in terms of being useful to me. I have for a long time had the 1984 combined dataguide version, and actually bought a second dataguide in case the development dial was ever lost or damaged beyond repair. The dataguide recommends a starting development number, and the dil, then presents the time temperature combintaions that match that development number.

I last weekend shot a series of head shots for an upcoming theatre production on plus X, and used a lens hood, and knew that the lighting ranged between f/8 and f2/8 (ie 4 stops) on the set that I lit between the forehead closest the soft box and the backdrop. I developed in d76 1:1, which had a DN recommended of 36.5. The adjusting factors tabulated to an addition of 3 DN's, which I think about and extra 30%. I warmed the chems to give development time around 8 minutes to match the adjusted development number. The negs came out beautifully developed and printed very easily on a nuber 2 contrast grade of paper.

 

[RalphLambrecht]

Thanks you guys, looks like I'll try the 20% increase, or around 13 minutes and 12 seconds with D76.

If you do that, I like to welcome you to the club of never-ending-experimentation.

You are much better off doing a proper film test. It takes six rolls of film and a weekend, and you are ready to take control. Trial and error will take much more film, goes on forever and will always leave you wondering.

I suggest Phil Davis' book, 'Beyond the Zone System' for details about the test. Don't let the title scare you.