Achieving consistency - what variables to fix?

DocFrankenstein · Jun 10, 2005

I want to have consistency in my darkroom. From the exposure (I'll get a light meter) to the print.

Basically, I want the whites to be white and the shadows black. What can I do to get as close to that as possible?

Let's not consider artsy exposures or backlit subjects. Let's say my aim is something of a documentary photographer. The lighting is straight and I want the prints to look like I saw them.

So, I take the ambient reading and take a picture.

Then develop my negs:

1) Developer, 20`C... new fixer for every roll... Same concentration. Time/shaking is always the same.

2) Stopbath - not a big influence on the concentration/time. Right? As long as it's approximately the same and I don't keep it in for too long, it's ok?

3) Fixer - I have no idea about this one. How does time/concentration in the fixer affects the negative? If it didn't get enough time, it'll turn black with time. What if I keep it there for too long?

4) Then washing. I don't know I'm gonna use photo flow, since I'm only starting.

Then printing...

Theoretically, all of my negs are the same at this point. White whites, black blacks? So I wouldn't have to even do a test strip after I've done it a couple of times, right?

So, I set the enlarger to f/8 f/11 and expose.

Developer concentration I won't be able to keep constant. Nobody discards a tray of developer for every photo. Then stop it and fix...

Is this gonna give me good results or is it noob nonsense?

Thank you for your comments

terri · Jun 10, 2005

It's not that it's *nonsense*, but it sounds like you're looking for a *one size fits all* approach to printmaking, and it just ain't gonna happen.

It sounds like you also are talking about controlling contrast, and you can do that at different times along the way, beginning in camera by using different filters, green, yellow, red....and keeping an exposure log so you can view the results later.

You can also control contrast during printmaking; adding magenta filtration, changing your paper grade, etc. Even the type of developer comes into play here; some are known to develop softer and open up shadows while others are more aggressive and give more contrast. You can even play with 2-bath developing for more control.

So....it all gets back to how hard it is to leave the darkroom once you get in there and start experimenting. :lol:

Keep notes on everything!! The more you do, the more you'll learn about what gives you the results you're after.

I'm sure others will weigh in here with even more variables to consider.

KevinR · Jun 10, 2005

Unfortunately, it isn't that easy(but I'm not saying it's hard either) It will just take time. If you look at some of the paper developers, different dilutions will boost contrast or make it more subtle. The papers are different and even different batches of the same paper maybe a little different too.

3) Fixer - I have no idea about this one. How does time/concentration in the fixer affects the negative? If it didn't get enough time, it'll turn black with time. What if I keep it there for too long?

Mix it to directions and you should be fine. I use the same fix for a good number of rolls before I change it. Haven't had any problems. I will usually fix for about 7min. I think 5min is the recommended time. You really can't over fix.

4) Then washing. I don't know I'm gonna use photo flow, since I'm only starting.

I would use it if I where you. It is cheap and a bottle will last a long time. Makes drying the negs that much easier. You don't get the water streaks.

ksmattfish · Jun 10, 2005

DocFrankenstein said:
The lighting is straight

This is the problem; there is rarely such a thing. Except in the studio, or other places with controlled lighting, the light will always be different. If your time, agitiation, temp, etc... are always the same then you will have contrasty negs from shooting in high contrast lighting, and flat negs from shooting in low contrast situations. A high contrast neg is going to need different treatment in printing than a flat neg.

Through testing you can determine the changes (usually in exposure and development times, but it could also be in temp, dilution, agitation, etc...) necessary to take any particular range of tonal values in a scene, and expand or contract that range to a personal standard that works well for printing.

In general, with BW neg film, you might start out with something like this. Measure the range in stops between the most important shadows where you want full detail, and the most important highlights where you want full detail. If this range is 5 stops, then expose and develop as "normal" (normal for one photog is not necessarily normal for the next, even if they are using the same gear, film, and chems). If there is a 6 stop difference, over expose 1 stop, and decrease development time by 1 stop (N-1). If there is a 4 stop difference, under expose 1 stop, and increase development time by 1 stop (N+1). How much time is a 1 stop change in development time? Once again, it can only be determined by personal testing.

Start reading anout the zone system and testing, this isn't something that you'll learn overnight.

Ansel Adams books: The Camera, The Negative, and The Print (3 books)

Henry Horenstein books: Black & White Photography: A Basic Manual
Beyond Basic Photography: A Technical Manual

ksmattfish · Jun 10, 2005

DocFrankenstein said:
2) Stopbath - not a big influence on the concentration/time. Right? As long as it's approximately the same and I don't keep it in for too long, it's ok?

3) Fixer - I have no idea about this one. How does time/concentration in the fixer affects the negative? If it didn't get enough time, it'll turn black with time. What if I keep it there for too long?

Strong acid stop can react violently with developer saturated emulsion, and cause mini explosions that actually blow pinholes in the emulsion. This is typically a bigger problem with medium format and large format film, than 35mm.

Take a bit of spare film (like the leader you cut from a roll of 35mm film to load it on the reel). Dunk it partway in the fixer, and time how long it takes to go clear. Twice the clearing time is your fixing time. This will usually be between 3 and 5 minutes, although some films take up to 10 min. It also depends on what kind of fixer you are using.

DocFrankenstein · Jun 10, 2005

ksmattfish said:
This is the problem; there is rarely such a thing. Except in the studio, or other places with controlled lighting, the light will always be different. If your time, agitiation, temp, etc... are always the same then you will have contrasty negs from shooting in high contrast lighting, and flat negs from shooting in low contrast situations. A high contrast neg is going to need different treatment in printing than a flat neg.

Through testing you can determine the changes (usually in exposure and development times, but it could also be in temp, dilution, agitation, etc...) necessary to take any particular range of tonal values in a scene, and expand or contract that range to a personal standard that works well for printing.

Yeah, that's a big problem. I don't have enough knowldegde to make sense of it all yet.

I'll go read those books and find out how do develop for contrast and how to develop... the opposite. :mrgreen: I'll also need to know how variable contrast papers work, and how the different contrast filters are used, cause right now I have no clue.

KevinR · Jun 10, 2005

The VC papers are pretty easy. If you where to print without a contrast filter in, it is essentially a #2 grade. That would be a starting line. So if you need more contrast after running a test, you would put in say a 2 1/2 filter or a 3 filter. If at no filter, it has too much contrast, then you would put in say a 1 filter or a 1 1/2 filter to lower it. Again, there are variables, but the learning curve isn't that big. Once you start doing it, you get a good feel for what you need to do. Look at your prints and compare to some really well printed work and then you get an idea to where you want or need to be.

ksmattfish · Jun 10, 2005

DocFrankenstein said:
I'll also need to know how variable contrast papers work, and how the different contrast filters are used, cause right now I have no clue.

Well, they work because there are different layers of emulsion that are sensitive to blue and green light, but all you really need to know is that more magenta increases contrast, and more yellow decreases contrast. Or even easier, if you have a set of multicontrast filters: 00 (or some sets only go down to 0) is the lowest contrast, and 5 is the highest contrast, with 2 or 2.5 about in the middle.

When you get that down we'll move on to split contrast filtering (using more than one filter/contrast grade on the same print).