Expose For Highlight or Shadows

Ian-Barber

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When trying to calculate your base exposure under the enlarger, do you find it easier to calculate your base exposure on the high or low values or do you calculate It on the most important part of the image and work the rest around it
 
The age old rule of thumb is Expose for the shadows and Develop for the highlights, the Zone System is just a way of doing this.

Ian
 
Firstly, you don't calculate at all. You look. You make a test strip. If that doesn't give you enough information, you make another one, and so on. You do as many test strips as are needed. You might need to change grade and make more tests.
It's a good idea to place your test strip so that it shows the effects on the most important part of image. Only you can decide what this is. If you get that right, everything else can be adjusted.
After your test strips have given you a reasonably good idea of exposure and grade, you make a work print. This is not the final ("fine") print, but it does tell you if your previous decisions are right. It should be at the same size and on the same paper as your final print.
If your work print is moderately close to being right, you might then decide to make another work print, perhaps changing the grade or the exposure slightly. This is to be expected, as it will be the first time you have seen the whole image in a print.
Seeing the image as a print might lead you to change the cropping because negatives are hard to judge.
At this point, you may even decide to change your mind altogether about what the print should look like and this will mean beginning at the beginning, with fresh testing.
From the work print you decide on any dodging and burning that's needed. Some workers draw a diagram onto the work print to guide them, if it's complex. You may, for instance, need to hold back one part of the image, and then burn back a small part inside that area. You may not get the dodging and burning right the first time and this is also to be expected.
You may decide that this image needs remedial split-grade printing and this would naturally involve further test-strip making, another work print and perhaps another dodging and burning pattern.
I cannot emphasise enough that printing is not a simply matter of adjusting the highlights or shadows, but of looking at the whole image, and making it the best you can. The only way is to keep on trying and looking with a critical eye until it is right. Lock the darkroom door. It will get easier with practice, but only with practice. A fastidious printer has a full wastepaper bin.
Ian's advice above, although excellent, is for negatives. We almost invariably develop prints for a standard time.
 
Yes missed the word enlarging :D. Was thinking of negatives.

I still expose for the shadow detail when printing and vary the contrast to achieve the highlight detail I require, using dodging or burning for localised control. Sometimes using flashing to tame highlights where burning in isn't ideal.

Ian
 
I don't think we're ready for flashing just yet. Another thread, perhaps.
 
Yes missed the word enlarging :D. Was thinking of negatives.

I still expose for the shadow detail when printing and vary the contrast to achieve the highlight detail I require, using dodging or burning for localised control. Sometimes using flashing to tame highlights where burning in isn't ideal.

Ian

The exposure time for shadow detail varies across the contrast grades. So if you test at grade 2 then do a print and find you really needed grade 3, then you will still have to do another test print to find the best shadow detail at grade 3.
So nothing's simple!

Alan
 
I would think like Alan, but it would really depend on what I thought was important in the subject-matter. Everything fits around that. Shadow detail may be important, but it's not the be-all and end-all of printing. I like shadow detail myself.
If I may give simplistic examples, consider a nighttime scene. Very often the shadows will be black to the eye and retrieving the utmost detail from them will render the scene as a daytime image. That may be our aim of course, but in general we don't do that. Simpler to return in the morning.
At the other end of the scale, consider a scene made up of sunlit snowdrifts, where there may be no shadows at all.
I don't suggest that these are typical subjects, but I do suggest that we print by eye, so that each print presents different problems of both technique and visualisation.
Technique can be taught or learned from textbooks, but visualisation...
 
A method I often use is to pinpoint the main area of interest in the photograph. If this area also has the brightest highlights and the darkest shadows, so much the better. I cut several small sheets of paper - big enough to cover this area, then expose them one after another by placing them in turn all on the same spot, using the contrast grade I think they will need. I expose them for half-stop differences, say, 10, 15, and 20 seconds, then develop them all together.
The results usually point the way forward. The advantage of these test "patches" over the more usual test strip, is that it allows you to compare like with like.

Alan
 
The exposure time for shadow detail varies across the contrast grades. So if you test at grade 2 then do a print and find you really needed grade 3, then you will still have to do another test print to find the best shadow detail at grade 3.
So nothing's simple!

Alan

You'd need to do a new test strip anyway to evaluate the highlight details as well at a different grade, it's the overall balance. I like good shadow detail so place those first then control the highlights, the mid tones then fall into place nicely.

Ian
 
A method I often use is to pinpoint the main area of interest in the photograph. If this area also has the brightest highlights and the darkest shadows, so much the better. I cut several small sheets of paper - big enough to cover this area, then expose them one after another by placing them in turn all on the same spot, using the contrast grade I think they will need. I expose them for half-stop differences, say, 10, 15, and 20 seconds, then develop them all together.
The results usually point the way forward. The advantage of these test "patches" over the more usual test strip, is that it allows you to compare like with like.

Alan

I have just tried this Alan and so far so good. As soon as you posted this, I remember you mentioning it before but forgot all about it. I have just ordered this book from Amazon (£2.20) hope its the right one.

Screen Shot 2018-08-22 at 10.41.30.jpg
 
Alan, That sounds like a clever scheme. We all seem to be agreeing on the importance of test strips. They save a lot of paper in the long run.
 
I have just tried this Alan and so far so good. As soon as you posted this, I remember you mentioning it before but forgot all about it. I have just ordered this book from Amazon (£2.20) hope its the right one.

View attachment 1163

Yes Ian; that's the book which recommends the test patch method.

Alan
 
Alan, That sounds like a clever scheme. We all seem to be agreeing on the importance of test strips. They save a lot of paper in the long run.

Yes David, a clever scheme. Not mine! I read about it in the Larry Bartlett book....

Alan
 
I guess my method is very similar to Alan's, although I do it all in one test strip. If the important shadow/highlight area doesn't fall comfortably into the exposures I expect will be close, I make another. However, unlike Ian I always base the initial exposure on the high values, then adjust grade/filter for the shadow areas. I'm sure either will work, it's just the way I was taught.
 
My initial test strip usually spans the diagonal of a print to contain highlights and shadows, it'll be series of 5 second steps, from that I'll choose exposure or change the contrast, then I make a single exposure on a similar strip, sometimes fine tuning with another.

Usually I know from looking at the projected negative exactly where to dodge and burn, that will usually be indicated on the test strips as well. Darkroom printing improves with experience, but is much easier if you have good negatives.

Ian
 
I'm told that if you put two economists in a room, you will get three opinions and evidently the same thing happens in darkrooms.
So far, I haven't read anything that isn't perfectly sensible, even though they differ. Some useful ideas too.
As Ian (G) says, it all improves with experience.
 
However, unlike Ian I always base the initial exposure on the high values, then adjust grade/filter for the shadow areas. I'm sure either will work, it's just the way I was taught.

Once you have established your time based on the high values, what happens to the high values when increasing the filter grade to darken the low values.
 
Something else that improves with practice is looking at your negative and estimating which contrast grade is likely to give you the print that you want. This is useful as getting close to the correct grade for your first test print is a good start. I believe some people use an electronic gismo of one kind or another to measure the negative's contrast range, then match this to the paper they intend using. Good luck to them! It has never appealed to me, though I can't really say why.
My method is to give the brain every opportunity to assess the level of contrast then keep out of its way and let it subconsciously work it out for me. So I hold the negative up to the light, but don't make a decision. Then I put it in the enlarger, switch on and look at the projected image on the baseboard - both with the safelight on and off- and still don't make a decision. Then I reach for the box of filters, and usually find myself picking one out without having to think about it. If I can't decide, then I put a 2.5 in.
I don't make a final choice until I am looking at the projected image coloured by the filter. I'm looking for a certain quite low level of contrast. If it seems too much I swap the filter for one of lower contrast, until the amount of contrast seems right. I catch myself comparing the darkest tone in the image with the black of the easel blades. These darkest tones have to look somewhere around mid-grey in comparison. I generally know when it looks right, or close.
Then I make a test print and find that I'm miles out!! Well no, actually. I'm usually close enough to make a good start.
Anyone daft enough to try the above method might like to make things easy for themselves by taking a negative that you have printed before, and put it I the enlarger with its "correct" filter - then observe the level of contrast in comparison with the black easel blades. This should help you get your eye in.

Alan
 
Ian B, the easiest way to find out is to try it. It's quicker than posting here and much more educational. How can we know what you want your shadows to look like?
 
As David says there are different approaches to printing, some swear by Split Grade printing, I'm not in that camp.

I learnt to develop and print properly at school from reading Curt (Kurt) Jacobson's books, Developing, and Enlarging. These are probably the best books on the subject but went out of print, Developing after decades and 24 editions in English and a few in other languages.

These days my printing is more akin to the approach of John Blakemore, Fay Godwin, John Davies, etc, although not learnt from them and hasn't really changed in 30 years.

Perhaps what's important is to choose one approach and evolve our own way of working, the danger is reading to many different approaches and getting muddled, this goes for film exposure and development as well as printing.

Ian
 
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