Pulling Delta 100 on a Contrasty Day

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I have a question regarding "pulling" my film (Ilford Delta 100 - rated at 80 ISO) during what is a very contrasty time of day. I have been testing my medium format equipment out on a particular cityscape, returning time and again to alter either one or two variables, either my lens, filter, or film, in order to see the effects in the final print without becoming confused as to what these adjustments are actually doing. The subject is a bridge, and I always set up in the same spot just as the sun rises. I've settled upon using Ilford's Delta 100, with an orange filter to reduce haze effects, tripod, sunshade, and cable release. I also use a hand-held incident light meter, although a spot meter is probably in my future. As expected, the prints always need significant dodging in order to bring out details under the bridge. I am content to do this rather than use a very low contrast filter while printing because the structural details above the bridge would go too flat otherwise.

My question is this: If I wanted to "pull" the film one f-stop(N-1), would I set the light meter to 40 ISO (half of my EI of 80), and then reduce the film development time approximately 20%? I use ID-11 at 1:3 dilution, and instead of 20 minutes development (under the EI 100 column), I assume this would become 16 minutes instead? Would N-2 require a light meter setting of 20 ISO and 40% development time reduction? I realize that I should be using a spot meter and measuring the overall scene brightness before deciding to reduce contrast in this way, but I'd like to see the effects anyway.

Thanks in advance for your help-- I'm getting a bit lost in reading "The Negative."

-- Dan Lohmann (dlohmann@irem.org), July 31, 2001


I;m not sure about your exposure & developing procedures BUT dont use the orange filter. I have had very poor results with Delta 100 & 400 using a orange filter. I am told that it is because Delta has reduced red sensitivity so using a red or orange filter results in wierd negatives.

-- Melvin Bramley (bramley@nanaimo.ark.com), July 31, 2001.

That's pretty brutal advice telling a landscape photographer not to use a red or orange filter! But compared to conventional films, I have noticed some very strange things with the T-Grain films with regard to filters. In comparing Delta 100 with TMX in Colorado (lots of blue light up here), TMX is more than 1 stop slower than Delta 100 with an orange (O2) filter. Even without any filters, TMAX is about 1 stop slower than Delta 100 up here. I have tested with Rodinal and XTOL. I am not sure I mind the "weird" color renditions, but getting accurate exposures is pretty difficult.

-- Michael Feldman (mfeldman@qwest.net), July 31, 2001.

Actually, the contrast tends to vary with the color of the exposing light. Most conventional emulsions tend to gain about the equivalent of an N+1 level of contrast when exposed through a deep red filter. Interestingly, Kachel reported the reverse with T grain films, a lower contrast when exposed through a deep red filter. I've never seen an explanation for this effect but it is worth controlling for in developing if you expose through deep colored filters.

In response to your question, many photographers like rating their film a bit slower and pulling development a little. This moves the shadows off the toe and provides better local contrast in the shadows. Cheers, DJ

-- N Dhananjay (ndhanu@umich.edu), July 31, 2001.

Yes, that's what I am seeing. Significantly less contrast using TMX with an Orange (O2) filter compared to Delta 100. Also, about 1 1/2 stops more exposure (compared to Delta 100) is needed for shadow detail.

-- Michael Feldman (mfeldman@qwest.net), July 31, 2001.

Dan. The idea of 'pulling' a film is to decrease the overal contrast by shortening the development time. Whether you need to make an exposure compensation is really independent of this, and depends on how the scene is metered.
If you meter correctly by taking a reading from a key tone, then there should be no need to downrate the film.
If you take an average, or camera TTL meter reading, then the meter might be fooled by the wide brightness range of the scene, and tend to underexpose.
Really, the exposure and the development are two separate issues, and should be dealt with separately. Pulling the development doesn't do anything except lower the overall contrast of the negative, while changing the exposure only alters how much detail will be recorded from the the shadows of the scene. With a very contrasty subject, giving more exposure could be entirely the wrong thing to do, by pushing the highlights up into the unprintable region where the film curve goes nearly flat.
IMHO it's better to expose normally, and use a compensating development technique, rather than a straight 'pull'. Compensating development means starving the film of developer, usually by using a more diluted developing solution. This naturally limits the maximum density of the negative, and leaves the highlights printable.

-- Pete Andrews (p.l.andrews@bham.ac.uk), August 01, 2001.

I've used Delta 100 quite a lot with with #25 and #23 filters, and I have found the results to be perfectly normal. I don't think Delta 100 has abnormal red sensitivity. TMX is another story. Because TMX does have heightened red sensitivity, it responds very strongly to a #25 filter. I find that I have to add about an additional stop (4 stops instead of 3) in exposure, and that shadow areas can be very tricky since it is difficult to determine how much they will darken.

Keep in mind that when you use a filter to darken the blue sky, it also darkens the shadows. Shadows are most typically lighted by blue light--light reflected from the blue sky, not direct sunlight--and this is more pronounced early and late in the day. Therefore, the filter that darkens the sky, also darkens the blue light of the shadow areas. This, in effect, adds contrast and means you will have to adjust your exposure for your critical shadow detail.

In terms of processing for a pull, as someone else said, I've found far more pleasing results diluting my developer opposed to pulling the time. Try diluting by 1/2, but be sure you use enough volume. If you typically develop one roll with just enough developer to cover the film, use twice the volume of the diluted developer. Otherwise, the developer may exhaust itself totally before reaching proper density. As for developing times with a 100% diluted developer, I'd suggest developing 50% longer as a starting point.

-- Ted Kaufman (writercrmp@aol.com), August 01, 2001.

As others have pointed out, there are a lot of various things at work here. As for the one stop pull on development, ILFORD's recommended time for ID-11 1+3 is 15 minutes. This is determined by actual testing, not by any formula. We have no published test data for lower EI settings. I would not recommend diluting this developer any further, since you are already working with a very dilute solution.

Remember also that decreasing development will decrease contrast in the whole picture, similar (but not identical) to using the lower contrast printing filter. If you do not like the overall contrast when using a lower contrast printing filter, you may not like the contrast from a pulled negative. Only way to know is to try.

Regards, David Carper ILFORD Technical Service

-- David Carper (david.carper@ilford.com), August 01, 2001.

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