PDA

View Full Version : Zone system for low contrast scenes?



Neal Shields
9-Sep-2004, 08:50
For the cost of film compared to the time it takes to set up an 8x10 shot, it is probably a good idea to make a back up negative. I usually do.

The other day I photographed a very low contrast scene; a muddy creek bed in full shade. I used Tmax 100 and “overexposed” by one stop. I then tray processed one negative in Ilford developer mixed 1 to 4 from the concentrate, continuously removing the bottom negative and putting it on top in a stack of 8. I processed them for 8 minutes at 68 degrees (the bottle recommended 7 minutes). I pre-soaked the negatives for 4 minutes in plain water before beginning development.

After all that, the negative was still a bit low contrast, so I processed the second negative exactly the same way except for 12 minutes. It has a lot more “snap”. In fact I now wish I would have went to 15 minutes.

I doubt if I will run out of paper grade printing either negative. So my question is: if I print the second negative on say grade 2 paper and the first negative on grade 3 paper will I be able to get the same quality print?

I suspect I will try it but I am interested in what people have to say. I am having trouble understanding why I need to use the zone system with modern variable contrast paper, unless I have a high contrast scene where I am concerned with pushing the highlights too far onto the shoulder.

Note: I work full time and have a 60-year-old house so I like to get final prints from darkroom time not just experimental data.

neil poulsen
9-Sep-2004, 08:59
Having a negative with contrast that's too low and trying to correct for that with paper grades just doesn't cut it. There's a certain amount of control one can exert with paper grades, but after a point, it's different. One doesn't get the same pleasing effect.

You might consider selenium toning the negative. You can use a 1:5 (toner to water) ratio, or even stronger and soak the negative for several minutes. By building up the silver rich areas on the negative, it gives the final print raised highlights. They can really pop out. I tried this with negatives taken in a very low contrast scene, and even an N+2 development was insufficient to raise the highlights far enough. The selenium toning did the trick.

N Dhananjay
9-Sep-2004, 09:33
If HD curves were absolute straight lines, what you are saying would be true - printing a low contrast neg on high contrast paper, and a high contrast neg on low contrast paper, would yield identical prints. In truth, there are significant variations from the straight line ideal. Films and papers have toes and shoulders. Thus, in reality, the prints do look different, beacuse the combination of toe on one neg plus shoulder on one grade of paper rarely matches up exactly with the toe on another neg and shoulder on another grade of paper. A complicating factor is that the ability to see the difference also depends upon the distribution of tonalities in the scene. And finally, all this means is that the prints will look different - the better print will be a judgment to be made by the viewer.

One advantage of aiming at a middle grade paper is that it gives you room to move to either side. In my experience, a good print has more to do with the proper local contrast than the overall contrast (or luminance range). So, having room to move on either side is an advantage in that it lets you fine tune local contrast with paper grade (which is often the only easy and sizeable control we have during printing) and dodge/burn to control overall contrast.

Cheers, DJ

Paul Butzi
9-Sep-2004, 09:53
Neal writes "So my question is: if I print the second negative on say grade 2 paper and the first negative on grade 3 paper will I be able to get the same quality print?"



You can certainly get quality prints from both negatives. They might be indistinguishable, or they might have different tonal distributions.



I tried this experiment with Tmax-100 and Ilford MG IV fb paper. You can see my results at

http://www.butzi.net/articles/zoneVC.htm (http://www.butzi.net/articles/zoneVC.htm)

Mark Sampson
9-Sep-2004, 10:26
Of course the answer is "Try it". You have two negs of different contrasts, now make the best print you can from each and decide which you like better. You'll learn something about printing, too. Paul Butzi's grayscale tests provide interesting data- but it's even better to see it in a photograph.

austin granger
9-Sep-2004, 13:43
Just wanted to second neil's suggestion of selenium toning the negative; it has an effect much like expanded negative development. It will raise the high values yet (and this is the important part) mostly leave the lower values alone. This is quite a different result than you'd get by simply going with a higher contrast paper.

Neal Shields
9-Sep-2004, 14:42
I like the selenium toning idea because it gives me an option that I can decide to implement or not after seeing the first print. If I us N+ development and don't like it, I'm pretty much stuck.

This may not be the best photo forum on the internet (probably is) but you get the best and most well researched and thought out answers here.

I am thinking about trying to standardize my procedure. I can't afford to make more than two negatives per scene. Everything is a contact print so I'm not worried about grain. For low contrast scenes, I am thinking about making one exposure at the "correct exposure" and doing N+1 development and a second exposure at one stop over the "correct exposure" and deciding on development after I see the first negative.

For high contrast scenes, I will make both exposures at the "correct exposure" and develop the first negative normally and then make the decision to go over or under on the second negative.

I think that I am going to mark all my plate holders so one side is normal and one side is plus one stop. This will allow me to keep them stright if I have different exposures and won't mater if both are exposed the same. (Sometimes I am not as good at keeping notes as I should be or being able to find them when I get ready to go into the dark room.)

Brian Ellis
9-Sep-2004, 15:06
Rather than making two negatives and maybe developing both or throwing one away, why not do proper zone system testing, then make one negative using the correct exposure and development time for the result you wish to achieve? You'll save time and money, double the number of different photographs you can make on a trip, and obtain better results than the somewhat "hit and miss" method you're thinking of using. If you don't want to undertake the testing yourself let The View Camera Store do it for you. They charge about $30 and you would spend close to that on film making traditional zone system tests.

jim Ryder
9-Sep-2004, 15:36
In a hardware store one day I saw a young woman wearing a t shirt that read "Ansel Adam's Brackets"

Hans Berkhout
9-Sep-2004, 16:53
Like Brian explains, you can't get around testing your materials for filmspeed and dev. time. If the contrast range is very low,say 3 zones, then you have options (for which you should again do some testing): total development, long exposure (could use ND filter) forcing you into the reciprocity failure area, and selenium intensification of the neg. Subseqently you could then vary your paper grade and/or bleach the entire final print somewhat, so as to bleach the lighter areas which will increase the overall print contrast.

David Karp
9-Sep-2004, 17:29
Not to question Brian's comments. Knowledge of your materials eliminates many problems.

However, even if you know your materials, it might be a good idea to keep making two exposures of each photograph you make. I got this idea from John Sexton at a workshop, and it makes sense to me. That second exposure makes it less likely that some mishap will destroy a photo that you really want to print. Mistakes in processing, a dumb mistake while exposing the film, dust spots in the sky, and many other problems can be remedied if you have that second sheet held "in your back pocket." I have experienced this firsthand. I dropped a wet sheet of film on the floor, then stepped on it (duh!), scratching it in the process. I was happy to have the second sheet.

Just a thought.

Donald Miller
9-Sep-2004, 21:03
"I used Tmax 100 and “overexposed” by one stop"

Overexposing is conducive to reducing contrast rather then increasing contrast.

Robert A. Zeichner
10-Sep-2004, 05:25
Donald raises a very important point. Typically you over expose and under develop to reduce contrast and do the opposite to enhance contrast. I just recently returned from a trip to the Greek Isles where I spent two weeks photographing architectural subjects. Everything is whitewashed in that part of the world and with the high reflectivity of these surfaces, shadow areas were never more than 1-1/2 to 2 stops darker than sun lit surfaces. The answer (and this, I tested before leaving for that trip) was to place highlight areas in zone V or VI and giving +2 or +3 development to expand the dynamic range. Only minor adjustments were needed in the darkroom. In an overly gray situation such as the one you described, I would probably have given +1 or +1-1/2 development, but would not have overexposed.

Neal Shields
10-Sep-2004, 17:07
I thought you underexpose when you know you are going to overdevelop to avoid pushing the highlights on to the shoulder. If I have plenty of room, I overexpose anyway, even if I am going to overdevelop to increase contrast.

Is this wrong?

I just have a hard time for some reason not giving it that extra stop on 8x10 where grain isn't an issue.

Aaron_3437
11-Sep-2004, 07:11
" fine tune local contrast with paper grade (which is often the only easy and sizeable control we have during printing) and dodge/burn to control overall contrast".

Thanks DJ. Always something useful to learn from you.

Robert A. Zeichner
11-Sep-2004, 13:13
"I thought you underexpose when you know you are going to overdevelop to avoid pushing the highlights on to the shoulder. If I have plenty of room, I overexpose anyway, even if I am going to overdevelop to increase contrast.

Is this wrong?"

You may be dragging lower zones upward to a degree that defeats your objective. Let's say as an example, your muddy creek bed scene has a dynamic range of 2 stops from the lightest highlight with textural detail to the darkest shadow, also with that degree of detail. When you over develop film the values at or above zone V will respond more dramatically to that overdevelopment than values below zone V. The higher the value, the more response, the lower the value, the subtler the response to overdevelopment. So to expand the dynamic range in the finished negative, you might want to place the highlight area in zone V and give +2 development, moving that tone up to zone VII. The part of the subject that is in metered zone IV will also get denser, but not to the degree that zone V tones did. The part of the subject that was in metered zone III will respond even less, hence allowing the dynamic range on the negative to expand. If you were to arbitrarily over expose by another stop, what was in metered zone III will now lie in zone IV and is going to get denser, faster when given +2 development and what was in metered zone V will now lie in zone VI, pushing itself into zone VIII on the finished negative. Depending on what film you are using and how much local contrast exists in the highest measured zone, you might, repeat might, find that certain highlight detail is too dense for comfortable printing. Without being able to actually see your scene and measure it carefully, I'd be sticking my nexk out in saying what you did was wrong. But, judging from the results you said you got, I would guess that if you had not over exposed and gave a little more development, you would have an easier time printing the negative. All I can say is to try it! And if you do, please let us know how your resuts changed.