Increasing Negative Contrast

Ian-Barber

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If you are struggling to get more than 3 or 4 stops between the darkest and lightest part of the scene would you think about increasing the development time for sheet film N+

If so, would you still rate the film as you would for N development or would you under-expose the film by say one stop.
 
I'd be wondering about the lighting and the nature of the subject, given the normal differences in subject brightnesses and lighting ratios. However...

I'd personally increase the development time and leave the exposure untouched. But this is just a gut feeling as I've never met this situation in practice. If the negative is to be scanned and printed digitally, I wouldn't even bother doing that as the contrast can easily be increased - far more easily than with a wet print.
 
I often get those reading on a dull day. Today for example, I was metering some flowers in a pot in the garden. If I had placed the darkest part on ZIII the petals would have only been on ZVI.

I was thinking of N+1 to see if I could get better separation in the middle
 
If this is something that often happens, then I assume that you find you can't get a good result from scanning and printing digitally. In that case, I'd certainly try increasing the development time.

If I don't say this, I'll be annoyed with myself, so: - Zone VI might be the correct placement, depending on how you want the petals to appear. Too dark if a white rose, but perhaps too light if a deep red one.
 
Presumably you are expecting to make a print with bright highlights and deep shadows rather than reproducing what you are seeing in the real world. Otherwise, why would you want more contrast?
So yes, increase development by all means. You might like to do some testing first and advice is readily available elsewhere on the web. Some people seem to find a densitometer is essential to their happiness but there are simpler methods and those who use them don't seem to produce worse prints than the who do. The choice is yours. Simple trial-and-error works well if this is not a vital and unrepeatable shot.
Can't see any need to adjust exposure in principle. No harm in moving Zone 1 up a smidgeon above FB+F. N-minus dev might need some extra exposure because even though the effect is mainly seen in the darkest parts of the neg, marginal shadow detail might become unprintably thin.
Contradicting what I said above, if the scene really is as flat as you say, why not give more exposure anyway, to shift the whole neg onto the steepest part of the curve, thereby avoiding the flat toe altogether (and the flat shoulder too, of course)? This doesn't exclude increasing development time, of course.
An unkind thought, for which I apologise in advance: Have you checked your metering method? I only ask for completeness, not because I doubt you.
Zone 6 equals Caucasian skin tone, which seems about right for a lot of flowers.
 
I was intrigued by your findings, so out of curiosity, I took my meter out into the garden. It's grey here, overcast but bright this afternoon. With my back to where I know the sun would be, I chose a pale cream-coloured rose and placed it on Zone 6. With that placement, the lawn fell on Zone 5 and the soil on Zone 4. There were darker areas underneath the plants of course, but I was surprised at how small the range of tones was.
Not at all what I would have guessed by eye – I'd have thought that with the grass pegged to Z5, the rose would have registered Z7. There may have been small, brighter areas on the petals, but too small to meter with a one degree measuring spot.
 
Having rethought this through, I could have placed the petal on Zone 6 which would have raised the low values and then darkened down the low values in post production.

I think I was aiming to get both the dark values where I wanted then during exposure and then move the high values in development
 
Yes, that would be the normal way to do it. For my scene, although I didn't make an exposure, it would have been N+1.
In actual fact, as I now seem to be develop routinely to about N minus 1 for convenient scanning, it might really be N+2 or thereabouts. There's no end to the complications we can devise for ourselves, is there?
Best of luck with the next exposures.
 
In actual fact, as I now seem to be develop routinely to about N minus 1 for convenient scanning, it might really be N+2 or thereabouts.

Are you doing this to place the lower values further onto the straight portion of the curve to give you more separation
 
What I've found about scanning as opposed to "wet" printing is this: You can print through almost any negative density if you expose for long enough, although it may be tedious and the results may not be optimum, but if a scanner cannot penetrate a dense neg, then nothing will make it, and you've lost the image. I like to give adequate exposure for the shadows to give scannable detail and no highlight clipping. Typically, I expect my negs to be boring and the basic scan to look a little bit dull. Ideally, in Levels, the scan should just fit nicely between the 0 and 255 points but I prefer to have it fall a bit short at both ends.
I seem to be painting a picture of someone who is in minute and rigid control of the process, but this is not true. I am constantly amazed when something works, with the same astonishment that we all remember (we do, don't we?) when our first print came up in the developer.
 
I suppose the question here is not to confuse exposure and development for Darkroom printing and exposure for digitally scanning something which I think is often confusing when listening to advice about negative zone placement, development and contrast as they are a totally different ways of working.

A bad exposure be it over or under would be extremely difficult to print and achieve acceptable results from the darkroom, conversely the same negatives scanned would prove easier to get a decent print given there is more control over contrast and masking digital working in say Photoshop.

Its relatively easy working on a scanned negative and moving tones from say zone 3 to zone 4 or from zone 6 to 5 or vica versa whilst still retain decent contrast (much harder working wet).

I think that working totally analog demands much more care in exposure and development with little room for error, working in the digital way to produce a print is far more tolerant to user error and not as critical.

I also agree with David M if you can get your scan to be between the numbers you are well on your way in making a decent picture/print, with a little knowledge in how to selectively increase and decrease contrast which in turn has an effect on tones in Photoshop makes this process easier and far less demanding then working wet.

PS not saying better only easier
 
I am guessing that many, if not most, of the members of this forum will have experience of darkroom printing. The Zone System makes sense if you've had the opportunity to make the mistakes that it can help to cure: over- or under-exposure and development, and why they matter. The biggest sins seem to remain the same – under-exposure and over-development.
(Digital photographers appear to resolve all difficulties by just turning up the ISO to sixty-four zillion-ish.)
I've now just had the thought that Photoshop makes much more sense to darkroom workers. Why are the darken/lighten tools called Dodging and Burning? Unless you've done it with film, Unsharp Mask makes no sense at all for a tool that increases edge contrast.
Although I haven't seen it mentioned elsewhere, I find that Photoshop offers opportunities for micro-dodging and -burning that are physically impossible with wet printing. You can adjust individual eyelashes...
I have to repeat Martin's sensible caveat: this is not necessarily an improvement and it can eat up time and backache. I can't speak for Adobe CC Ransomware but Photoshop CS 6 gets me just above the shoulder-blades and below the neck. Where do others suffer?
My apologies if I've strayed too far from moving the petals from Z6 to Z7.
 
Given that as far as I know you're scanning and printing digitally, you may well find that so long as you can get detail from the highlights that's all you need in the negative. I discovered long ago that the scan settings make an enormous difference to the contrast range of the resulting print (if printed straight from the scan) as this pair shows (same negative, different scanner software settings)

Hutton le HoleS.jpg

I also found some time ago that a sheet of film that visually appears to be unexposed, clear film can still hold an image that the scanner can drag out, albeit with many gaps in the histogram. That still means that there is shadow detail that can be picked up even in the deepest shadows that could theoretically be used.
 
I am pretty comfortable with scanning, I want to learn more about how different developing techniques affect the outcome on the negative.

I am trying to avoid the expense of wasting a lot of film doing tests but I am reaching the conclusion that in order to see what happens I do A,B,C I have little choice until I do it
 
I'm afraid that there's no real alternative to doing at least some testing.
But eventually. No need to rush.
Remember, we are not testing the response of film alone; we are testing how our particular system, methods, skills and print preferences and even our choice of subject matter perform. It's possible that one person agitates more or less vigorously or their darkroom room is slightly cooler or warmer than the developer, or their eyes perceive shadows differently from the next photographer. The local water may be more acidic or alkaline. One photographer may start the timer after all the liquid is poured in and another may do the reverse. For all I know, the brightness of our ground glasses may influence how we choose to expose. Bellows may have flare that helps to lift FB+F and improve shadow response, allowing us to reduce film speed less.
Most people seem to find that they more-or-less halve the film speed and reduce development by about 20% for normal development. There are similar common findings for plus and minus development. All this assumes a fairly standard film such as FP4 or Tri-X and a fairly standard developer, ID11 or D76. I believe that these developers are used when manufacturers determine film speed.
These methods were all devised in the days of single grade papers where careful matching of negative to paper was essential. I believe the same is true today for alternative processes (has film been promoted to "Alternative" nowadays?) such as Platinum printing.
As Stephen pointed out and illustrated so elegantly above, the scanning process is flexible enough that as long as the image data are captured on the neg, they can be retrieved by software, although naturally, a controlled negative will make life much easier. There's little need to agonise over hitting exactly 0.01 over FB+F and a little extra density in the shadows will do no harm at all. The great vice is excessive density in the highlights, because scanners fail to penetrate excess density and highlight detail will be lost. There are ways of reducing density in negatives, but they all carry some risk.
I've found that when explaining to novice photographers why we do this or that thing, the explanation always seems to be that it will make the next stage much easier.
 
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I do enjoy your words Mr David M :)
 
Good heavens. Thank you. Not as much as I've enjoyed your images.
 
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In days of yore (Before retirement) ... using Kodachrome for 35mm work... and/or a LOT of Ektachrome in all formats.... usually 'ALWAYS' processed as "Normal/ Standard" E6 chemistry in a Wing-Lynch rotary processor

I now carry around a swatch of a scrap of a heavy weave white scrap of cloth 'rescued' from my wife's sewing bag. This swatch may be placed beside the subject (but sometimes 'hung' on one leg of my tripod If it is receiving the same 'light' as my subject of interest.... and a meter reading 'taken' and 'adjusted' placing 'placing' that reading value on 1/3 of a stop ABOVE "Zone VIII"... at manufacturers speed rating (except where detail in the lower 'zones' were of primary importance). Placing 'white with texture' on Zone VIII + 1/3 for commercial (ie Kodak's and 'my normal' processing) retains the 'Texture' in the high areas. I found that following that metering process with my B/W exposures continues to work very nicely.. since metering for the highlight detail and letting the shadows 'fall where they may' seems to work well enough for the MAJORITY of my images. There are a few occasions where the light meter reading 'range' is lower and on these few occasions I am usually willing to 'expand' the development time, in order to increase tonal range.

Ken
 
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That's a very ingenious system. Out of curiosity, how are you metering? Do you ever need to use contraction?
 
Metering?... with an experienced Pentax spot meter. I 'read' for the 'white-with-texture' and 'place' that reading on Zone VIII+1/3 and usually develop for "normal" development in Pyrocat HD with continuous agitation in a water-bath (a 'confiscated' Tupperware container that 'sits' on an somewhat ageing water-bed heater set down about as far as it will go). If the negative ends up needing a little more density and/or contrast, it usually has responded well enough with some dilute selenium toner. There are the occasional days.. usually when it is 'overcast' my Sekonic incident meter provides an 'adequate' reading when I may not have the time to make multiple 'spot' readings with the Pentax.

Now and again my 'gut instinct' has me make minor changes at the last minute. Since I rarely ever print on silver-gelatin paper now-a-days (and if I do it is on fibre only... I hate... and still refuse to use RC paper for personal use).. and on the odd occasion when I am asked to make a 'custom' print, it is always on fibre paper... and... I charge the client 'custom prices' since I consider 'my time, knowledge and experience' to be of 'real value'.

In the past few years, I have taken to print the majority of my negatives using the archaic non-silver photographic print processes and now, since my investment in an Epson flat-bed scanner earlier this year, I'm now taking the opportunity to scan and slightly enlarge my 4x5 negatives onto Pictorico for contact printing under my home built UV light source. Yes... it is a LOT 'slower' and a LOT more work, but is has become MUCH more 'satisfying'.. even though my 3 to 4 hour darkroom effort usually produces much lower 'output' count.

Both my film and print 'chemistry' is now made from 'scratch'... using only distilled water from the drug store for the developer... and the assistance of a three-beam balance for accurate measuring of the dry chemicals.

The 'old' saying... "You have either the 'equipment', the 'time and ability'... or the money".

Ken
 
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