Brief observation on compensating development with D23

[Ulophot]

Few may be interested; this is sort of niche post.

I have been retesting DD23, having had problems getting good results last time around, several years back. I have it under control now, though I have not tested exhaustively. I have been using David Kachel's SLIMT technique for compensation with D-23, which I normally use 1:1. This time I compared it with DD23 at N-2 and N-3, using 35mm to test grain differences as well as low-value support, since I do shoot 645 and 35 in addition to 4x5. Although other users of SLIMT have not confirmed my results, I find that SLIMT takes a little edge off fine detail sharpness in the smaller formats, and found that again this time. The comparison with DD23 is interesting in this regard. While SLIMT is visibly better at supporting the low values, DD23, using stock or 1:1, offers markedly finer grain, undoubtedly because the film is in the developer for a shorter time. For me, this is a consideration in some images and a nice alternate approach, using the same developer ( I use only one), to have in my bag of tools.

I use an EI of 200 for HP5 for either technique I find that I can produce an N-5 without difficulty with DD23, though it can benefit from an additional half-stop of exposure.

[John Layton]

Good for you Philip...and long live the niche! Would be nice to see some results here - although this would likely be precisely the kind of difference which would not be visible on our screens.

[Doremus Scudder]

The real advantage of using SLIMTs for contractions is that film-speed loss is generally less than just using reduced or compensating development. If you are easily able to give more exposure when making the negative to compensate for the speed loss with extreme contractions, then if is often a better choice to use the latter and forego the SLIMTs. That said, I sure need to be able to get almost full emulsion speed in many situations that require contractions, so SLIMT has an important place in my toolkit.

Doremus

[Ulophot]

In reply to John L, here is a comparison of two sections of enlargements from N-2 negs, the first using DD23, the second using SLIMT. Bear in mind that the difference is exaggerated here as a result of scanning the prints, compression of the original 1200ppi scans, and the fact that you're viewing 3x4-inch sections of what would be roughly 16x20 prints of these two 35mm HP5 negs. I did not sharpen the scans, but I did equalize the midones a bit using levels, even though this appears to make the DD23 neg have denser shadows than the SLIMT. These are taken from incomplete testing examples.

That said, like Doremus, I chose SLIMT for its superior low-value boost, as stated above and other places. I want to be able to make portraits in natural lighting with extended reflectance ratios without losing the shadows, e.g., a portrait subject in generous "environmental" cropping in partial direct sunlight coming through a window. I don't print above 11x14, so even significant cropping of a 4x5 neg leaves this a moot issue, but with 645 it peeks in, and, although I tend to keep 35mm for other purposes and hold print size to 8x10, the comparison testing has been useful for me.

[Michael R]

It would be interesting to compare the characteristic curves of both processes for speed, contrast, shape, density. I did some of that for divided development several years back out of curiosity but never tried SLIMT for anything (I find it needlessly complicated for severe contractions). This is the first time I've seen a blow up of the grain from a SLIMT negative and although the difference might not be visible until you get to significant magnification/enlargement, I'm somewhat surprised by the relative graininess of the SLIMT negative. Density differences might explain it.

[Ulophot]

In this very-much uncalibrated example, that's a good point, Michael, but in previous testing, comparing D23 1:3 vs. SLIMT for contractions, I matched densities fairly closely -- by which I mean, I have never used a densitometer but I made prints from negs at the same enlarging exposure and matched densities closely by eye. Even in an 8x10 of a yard scene, the 1:3 had a notable sparkle in comparison, which I then investigated with greater magnification to understand the cause. It was then that I first noticed the added grain and consequent loss of "sharpness" in fine detail. As I said above, the difference is exaggerated here.

I had originally hoped 1:3 would be my ticket to compression. That's a non-starter, since the shadows drop considerably. Coming back and rigorously testing DD23 over the past week has opened an alternate for me when I can do without the "SLIMT bonus."

[Michael R]

Quite right - contrary to what one often reads, diluting general purpose developers doesn’t help there. It’s pretty much a zero sum game. Divided metol-sulfite processes (DD23 being one example) does help somewhat in the sense it can give full film speed for some degree of reduced contrast. It also tends to have a straightening effect on a film’s characteristic curve rather than giving a “compensating” effect. For extreme minus development with full emulsion speed, a special purpose developer is usually best, although if SLIMT is working for you I don’t want to encourage yet more testing.

Having said all of this, make sure not to lose sight of tone reproduction (ie print quality). When you have an extremely wide subject luminance range and want detail everywhere (incidentally this is the situation more often than not for me), is massively reduced total negative contrast a better avenue to a great print, or are you just trading one set of difficulties for another - or worse? Is attempting to fit a negative density range onto the paper the best way, or are printing controls more powerful?

In this very-much uncalibrated example, that's a good point, Michael, but in previous testing, comparing D23 1:3 vs. SLIMT for contractions, I matched densities fairly closely -- by which I mean, I have never used a densitometer but I made prints from negs at the same enlarging exposure and matched densities closely by eye. Even in an 8x10 of a yard scene, the 1:3 had a notable sparkle in comparison, which I then investigated with greater magnification to understand the cause. It was then that I first noticed the added grain and consequent loss of "sharpness" in fine detail. As I said above, the difference is exaggerated here.

I had originally hoped 1:3 would be my ticket to compression. That's a non-starter, since the shadows drop considerably. Coming back and rigorously testing DD23 over the past week has opened an alternate for me when I can do without the "SLIMT bonus."

[Doremus Scudder]

Ruminating a bit on Michael's post above:

In my experience, extreme contractions (sometimes even moderate contractions) tend to result in too little local contrast to really make an excellent print. I find that N-2 is about it. And, I don't often use N-2 for subjects that the Zone System would normally indicate N-2 for, but rather for subjects that would require more extreme contractions. In other words, I find I get better results developing an "N-2 scene" at N-1 or even N and the dealing with the excess contrast when printing. Often, I'll decide in the field which area of the subject I want good local contrast in, meter, expose and develop for just that area and let the extremes fall where they may. Then I'll deal with them in the darkroom, first with lower contrast setting and traditional dodging and burning then, if that doesn't work, with split-grade printing techniques (burning a stubborn high value with a bit of max yellow first, to get a tiny bit of tonality going, much like flashing would do, and then using max magenta or even a +47 filter to burn in some darker values for texture, etc., etc.). I'll make a note in my exposure record that "this one will be a bear to print," or something like that.

The point being, that a, say, N-4 negative of an scene with a SLR that "requires" N-4 in Zone System practice, won't yield as good a final print as an N-2 negative of the same scene and a lot more work at the printing stage. Or, you'll have to actually increase contrast at the printing stage to get local contrast and end up doing as much or more work.

Similarly with expansions, I no longer develop anything much more than N+1, and usually only those things that would need N+a-lot-more according to the Zone System, preferring to boost contrast when printing.

I know the limits of what I can do on either end prints, and if the SLR of a scene doesn't exceed the extremes, I'll usually just develop normally, or just one plus or minus one way or the other.

True compensating development may need a different developer and a change in your agitation scheme. Still, there are tradeoffs there too, namely greatly reduced separation in the higher print values (something that's a bit maddening about PMK sometimes). That's usually better than the opposite, i.e., reduced shadow separation, but not necessarily better and often worse than figuring out a way to burn the area when printing. It all depends on the scene and how difficult that burning might be.

I use SLIMTs in much the same way. I'll start with a scene that needs say, N-4 and I'll give it an N-2 development combining SLIMT and my usual N-1 or even N development time and then deal with the resulting contrastier negative when printing. At least that way, I have the local contrast I want (or as much as I can practically expect) and just take the extra printing work as part of the bargain.

Best,

Doremus

[Ulophot]

Having said all of this, make sure not to lose sight of tone reproduction (ie print quality). When you have an extremely wide subject luminance range and want detail everywhere (incidentally this is the situation more often than not for me), is massively reduced total negative contrast a better avenue to a great print, or are you just trading one set of difficulties for another - or worse? Is attempting to fit a negative density range onto the paper the best way, or are printing controls more powerful?

A good point; a flattened range that has lost all life in tonal separation is self-defeating. Paper white is not always a sin, and in many cases, print flashing can take care of an extra stop of density at the top end with sufficient detail. Or, a mask. The art of print-making is open-ended, and don't we love it!

[Michael R]

Agree, and sometimes a great print is just plain challenging and takes a lot of work. There are few free lunches out there.

A good point; a flattened range that has lost all life in tonal separation is self-defeating. Paper white is not always a sin, and in many cases, print flashing can take care of an extra stop of density at the top end with sufficient detail. Or, a mask. The art of print-making is open-ended, and don't we love it!