View Full Version : Contrast control basics

Antti Aalto
7-May-2005, 17:03
I thought I'd ask a dumb question instead of trying it out to save trouble and money.
So far I've only made prints on Kodak Polymax II RC and developed them in Neutol. This is the only combination of fresh paper/developer I could get a hold of without having to order them. I get to use a Durst enlarger with a color head. I've been reading Adams's The Print which doesn't deal with variable contrast papers, but suggests that one can use different developer combinations to control contrast beside the paper grade selection. Since a color head can be adjusted to a minute shift in contrast, does this mean using different developer combinations has no real use anymore? Also can modern papers be affected by the choice of developer as much as it appears to have been possible in the past? Do RC and fiber base papers differ here or is it just a matter of the developer getting into the paper? If you compare two prints developed in different developers to the same contrast, is the difference in how they look - something that I might like to apply as a means to make the print look better? Or is the choice I'm facing just between using variable or non-variable contrast papers and then choosing between different brands of paper as well? In The Print Dektol and Selectol-Soft are suggested to be used as a pair. Any comments on what should I get to have a pair of developers to go with? What different papers should I try? I'm not asking what's the best paper, but I'd like to know some examples that make the general trends of what kind of look can be achieved clear. Combinations to yield the opposite ends of any scale would be welcomed, I suppose. I know it's not that simple but I need some solid examples to start with because otherwise I won't get to know what I prefer.Comments are much appreciated!

Oren Grad
7-May-2005, 18:24
Split development for contrast control is a trick that's useful primarily for graded papers. Using developers to control contrast is rarely worth the trouble with variable contrast papers.

In addition to overall contrast, developers can affect other things like the color of the print. Some people get very exercised about that, but I don't.

If you're just getting started in printing, I'd strongly recommend that you just pick one variable contrast paper and one developer - and one film, for that matter - and stick with them and the Durst color head until you thoroughly understand the characteristics of those materials. If Neutol and Polymax II RC are what's readily available, then just use those.

If you don't have a strong foundation of experience to work from and a disciplined approach to testing alternatives in a controlled way, it's very easy to spend lots of time and money trying different materials without ever understanding them or being able to control them well enough to reliably achieve the effect you want. Keep it simple at the beginning - the refinements will take care of themselves later on, once you've mastered basic printing technique.

Jim Ewins
7-May-2005, 20:33
Antii, you may consider joining a PSA portfolio workshop which circulates among its members 3 negative which everone prints. The completed prints are evaluated by the manager or master, asigns a ranking and comments on the attributes of the print. This method can be quite helpful. The Circuits circulate about 4 times a year. Circuits are availablr for 35mm, med & 4x5 formats. The cost is $3.50/year plus of course PSA membership. There are a number of other PSA programs to help the printer.

ronald moravec
8-May-2005, 05:54
A color head can be adjusted for much more than minute amounts for contrast control. This is all many people use.

Split developing can be used for contrast contol for graded paper, but why bother if you can use filtration?

Louie Powell
8-May-2005, 06:05
Atti -

Oren's suggestion to pick one paper and one developer for the purpose of learning is excellent. Photography offers an astounding array of variables. For a new person, the options may be overwhelming. You really need to learn the basics before you start exploring exotica.

A dichroic color enlarger can be used to adjust the response of variable contrast paper. You can find tables on the internet that suggest settings for various contrast grades. One thing to keep in mind - there is a hard meaning to contrast grade numbers (they are defined explicitly in ANSI standards), but when you are in the darkroom making real prints, what matters is that grade 4 is more contrasty than grade 3, etc. In practice, you make work prints and adjust the contrast settings (or filtration) to achieve the look you want - and never mind what the number is.

It is also possible to adjust contrast grades slightly by selection of developer, or by use of split development. Frankly, however, I would place that in the advanced technique category. It's useful if you need to make a microscopic adjustment (typically 1/4 contrast grade or less) in contrast.

Likewise, you can use print flashing, selective application of hot developer, and selenium toning to make small changes in contrast. Also techniques for making fine display prints.

Think of it this way - a mechanic's toolbox will typically contain a lot of wrenches, all of which serve the same function of tightening nuts. In photography, there are a lot of tools and techniques that achieve similar objectives. Experienced printers use many (if not most) of them to achieve their printing objectives. Over time, as you learn printing, you will pick up (and perhaps abandon) all kind of techniques as you hone your skills.

Jim's suggestion about PSA American Portfolios is excellent - I learned a lot about printing from some very fine printers though that community, and you make some great friends in the process.

Richard Schlesinger
8-May-2005, 06:41
You might want to get a couple of books that will be a great help and answer just about all your questions about printing. Ctein's book "Post Exposure" will cover most of your questions, and Steve Anchell's book "The Variable Contrast Printing Manual" both put out by Focal Press should answer all your questions about VC papers etc.

Ole Tjugen
8-May-2005, 07:17
I have a feeling Antti isn't in the USA, so joining the PSA may be difficult...

RC papers don't respond to different developers like graded FB papers do. And there are differences between graded FB papers too - some are almost more flexible than VC papers, while others just give the possibility of a slight adjustment.

I have never osed Polymax RC myself so I know next to nothing about it, but from what I hear it's a fine paper. Neutol I do know; a very fine basic developer.

I suggest you stick to those two and learn to use them for a while yet. If you want to play with different developers pick a Kentmere or Bergger paper, both brands have a wide variety of types to play with. Try one of their VC FB papers when you get to know your negatives, that will show the difference between RC and FB prints too.

8-May-2005, 13:04

Where do you live? You may want to attend our printing workshop in August. It will be a long weekend including: exposure and overall contrast control, dodging, burning, flashing, fiber paper processing, toning, print finishing. If you ar interested, contact me directly.


John Cook
8-May-2005, 13:15
Using an enlarger color head to control print contrast is certainly possible. Many printers swear by this method. But I have always felt that changing the level of enlarger head filtration has got to change the level of filter density in the light path. This, in turn, must require a change in exposure time and/or f-stop setting. And so you chase your tail around in circles.

Surely, variable contrast filters which are each calibrated to the same density (except possibly the most contrasty one which is exactly one stop thicker) must be much easier to work with.

Back in my commercial photography days, I was forced by impossible deadlines made by ignorant MBA's to shoot something when the light wasn't good enough. And when printing for clients who supplied negatives from other photographers, mostly novices, the contrast was all over the place. A major challenge which definitely required every grade of filtration available. And then some.

But now retired and photographing solely for my own pleasure, I can control the studio light ratios and work on location only during the best weather and time of day. Constant horsing around with print contrast is no longer necessary at all. The negatives are all perfect to begin with because the light was perfect before the shutter was tripped. It's definitely not a matter of great talent. Just patience.

Nick Morris
9-May-2005, 11:27
I use VC filters with a B&W enlarger. I have found that there can sometimes be what appears to me unacceptable contrast even with 1/2 step filters, and I will experiment with the controls AA wrote of in his book. Developers and developer strength can affect contrast of VC papers that I have used. Generally the filters offer sufficent control. I have not used a color head, so I do not know the degree of control they offer. As others have stated, stick with your set of materials until you understand how they respond the the various techniques you apply. What you learn from this will transfer to other materials and material combinations.

Paul Butzi
9-May-2005, 14:56
"A color head can be adjusted for much more than minute amounts for contrast control. This is all many people use.
Split developing can be used for contrast contol for graded paper, but why bother if you can use filtration?'

Among other things, as a general rule graded papers offer higher highlight contrast than VC papers do. I'm sure there are other reasons as well.

Paul Butzi
9-May-2005, 15:17
"...Steve Anchell's book "The Variable Contrast Printing Manual" both put out by Focal Press should answer all your questions about VC papers etc."

At one point, I made a list of all the errors I found in this book. The list was quite long, and included some really monumental errors which indicated that Anchell simply had not tried some things that he suggested - the biggest one that comes to mind is the oft-repeated suggestion that cyan filtration can be used as neutral density for VC papers (see the reasons why this is not so at www.butzi.net/articles/colorthe.htm (http://www.butzi.net/articles/colorthe.htm)). Given Anchell's reputation, I certainly expected better.

I'd suggest Tim Rudman's excellent books on printing, and Ralph Lambrecht and Chris Woodhouse's "Way Beyond Monochrome".

In particular, the latter has a method for calibrating to allow for the speed changes as you adjust filtration which is similar to (but simpler than, for some folks) the one on my web site.