edge100
Well-known
The nominal speed of Tri-X developed in Diafine is ~1250 (box says 1600 but that's optimistic, in my experience).
So shooting at EI640 and developing in Diafine is roughly a one-stop *over*exposure.
How to expose B&W film for scanners that aren't good at picking up shadows?
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The nominal speed of Tri-X developed in Diafine is ~1250 (box says 1600 but that's optimistic, in my experience).
So shooting at EI640 and developing in Diafine is roughly a one-stop *over*exposure.
dshfoto
Well-known
Moodlover,
You wrote, "I am scanning completely manually and attempting to boost the shadows"
-- It might be better to expose for the shadows, and then increase the highlights with curves.
Steve H.
You wrote, "I am scanning completely manually and attempting to boost the shadows"
-- It might be better to expose for the shadows, and then increase the highlights with curves.
Steve H.
x-ray
Veteran
Got to say this is a first for me. I've never heard anyone say they develop for the mid tones and agitate for the highlights.
I'm not aiming this at you. Sounds like you have a system that works for you.
One thing people need to know. Shadows are controlled by the exposure. There's minimal effect from development unless you're severely over or under developed. Highlights respond very quickly to development. A little bit of change + or - in time makes a big difference in highlight density.
Going down the tonal scale say to zone V, the same development that raises you maximum highlight 1 zone will have much less effect on zone V and even less on IV but greater effect on VI and VII. The farther down the tonal scale word shadows the less development and agitation have an effect. The higher on the tonal scale word highlights the greater the effect with each increasing zone.
The danger of developing for mid tones is the exaggerated effect on highlights and danger of blowing them out.
charjohncarter
Veteran
That (my post) was a little off subject. My theory is that shadow and midtones go to complete development while highlights continue developing and they are the last to go to complete development. So, I expose for the shadows and develop to where the midtones are almost developed to where I want them. Then I hold back agitation if I want to control highlight blow outs.
That is the theory, but it probably doesn't work in practice (only maybe with large format). Still, I generally minimally agitate to hold back highlights (mostly because I don't like highlights blowouts).
These thoughts I stole from DF Cardwell on APUG. Basically, this is compensating development. If you are interested you can read John Sexton's monograph on high contrast compensating development:
http://johnsexton.com/images/Compensating_Development.pdf
Ronald M
Veteran
#1 position key and fill at same distance & power.
#2 to get more shadow detail on film, expose more. No other solution.
#4 A better scanner if 1&2 do not work
#3 Do manual exposure scanning. If you need to expose heavily to get highlight separation, shadows will go black even there is detail on the film. Develop film less so highlight are less dense
Learn to print film. Principles are exactly the same.
x-ray
Veteran
I think there's some validity to your theory. Highlights deplete the developer faster than mid tones and especially shadows so with minimal agitation you can suppress highlights while fully developing the other values. Interesting! Sort of like water bath development.
shawn
Veteran
If 3 is needed also add 3a... bracket your scanner exposures and combine the scans in a type of HDR blend. Some scanner software has this as an option to do it for you.
Shawn
charjohncarter
Veteran
I shouldn't have really said my theory, as it was my interpretation of the ideas of John Sexton, DF Cardwell, and to some extent in the later writings of Ansel Adams (his HC-110 semi-stand development).
But in many ways if you don't wet print, you can spread the histogram out on your scanner and then take that image and do the same process digitally by careful use of the editing program's levels.
x-ray
Veteran
I'm really a tradiationalist. I've worked in a darkroom sixty years. When I was 8 my father started teaching me processing and printing. I've never lost the love for the darkroom. I do some very large digital prints up to 6x10 feet of my x-ray art but my personal photo work is still primarily B&W and wet printed. I moved to a new (semi)retirement home a little over a year ago and had a fabulous darkroom built.
Digital printing is really good now. My wife is a retired advertising art director and a couple of weeks ago I made two prints from the same neg. one was from a scan and the other wet printed. She's got a great eye for photography and she couldn't tell any difference other than one was a tiny bit warmer. If I hadn't known I'm not sure I could have told the difference. As good as digital printing is I just can't warm up to it for my personal work other than color.
Digital printing is really good now. My wife is a retired advertising art director and a couple of weeks ago I made two prints from the same neg. one was from a scan and the other wet printed. She's got a great eye for photography and she couldn't tell any difference other than one was a tiny bit warmer. If I hadn't known I'm not sure I could have told the difference. As good as digital printing is I just can't warm up to it for my personal work other than color.
charjohncarter
Veteran
I don't have a digital printer but my friend has spent way too much over the years for printers and especially ink. At first, although I wouldn't tell him, I did not really like his D-prints. Lately as you have mentioned his prints are good (just like yours).
One thing that I do is send my digital files to Costco which does wet printing using laser exposure. These are only printed on color paper. For B&W I really don't like these results. I have tried TRUE B&W paper (laser printed and wet developed) online from digital files and they are way better, but for me they are still a little (very little but enough) inconsistent to upset me.
By the way, when I was a dentist in the US Army we had Panorex X-RAY film. It was probably 4x10 or 12 inches. I would use these film as paper. I would print a negative and it would be a positive on the Panorex film. It was a dumb but I loved how they looked on my x-ray viewing light. I wish I'd kept them now that we have digital scanners.
x-ray
Veteran
[/QUOTE]
By the way, when I was a dentist in the US Army we had Panorex X-RAY film. It was probably 4x10 or 12 inches. I would use these film as paper. I would print a negative and it would be a positive on the Panorex film. It was a dumb but I loved how they looked on my x-ray viewing light. I wish I'd kept them now that we have digital scanners.[/QUOTE]
Quite a few ultra large format photographers use x-ray film in their cameras.
There used to be a Kodak product called fine grain release positive which was a printing film. It originally was the stock that B&W motion pictures were printed on for theatrical release from the negative. Kodak brought it out in sheets to print on for backlit display transparencies. It could be developed in deltoid and made rich looking prints.
By the way, when I was a dentist in the US Army we had Panorex X-RAY film. It was probably 4x10 or 12 inches. I would use these film as paper. I would print a negative and it would be a positive on the Panorex film. It was a dumb but I loved how they looked on my x-ray viewing light. I wish I'd kept them now that we have digital scanners.[/QUOTE]
Quite a few ultra large format photographers use x-ray film in their cameras.
There used to be a Kodak product called fine grain release positive which was a printing film. It originally was the stock that B&W motion pictures were printed on for theatrical release from the negative. Kodak brought it out in sheets to print on for backlit display transparencies. It could be developed in deltoid and made rich looking prints.
Highway 61
Revisited
Other posters gave you great information already but I may add that what I quoted above applies to positive slides, not negatives.
If, while scanning a negative, the scanner cannot "see" any details in the shadows of the positive image, this is mainly because your negative is underexposed.
There is a myth out there making people think that the scanner software can control the way the scanner will physically scan what it has to scan.
But the scanner software, if you use it so, will just modify (and, most of the times, badly deteroriate, with the exception of the multi-passes allowed by Nikon Scan and certain models of Coolscan scanners) the digital file created by the machine + software suite. The scanner is a peripheric machine plugged into a computer. It is here to make a digital file off an analog document thanks to the associated software which is here to allow the computer to drive the peripheric machine and nothing more. All you have to do while scanning is to generate a digital file which contains the most information at the best digital sampling ratio. Which means you absolutely must set the scanner software to TIFF with no compression whatsoever and at 16bits per channel with a full linear histogram.
Then if you look at the file created by the scanner on you screen you must see exactly the same thing as what you see when looking at the negative put on the luminous table.
Then you save the file, close the scanner software, and open and post-process the file in PhotoShop which is the only software which should be used for post-processing digital files created with a scanner because of the high quality of its algorithms (if the discontinued Nikon Scan software was actually a clone of PhotoShop, that wasn't for no reason).
Even the simple negative/positive job will deteriorate the file if done with the scanner software sometimes. With some scanners softwares, you also must scan the black and white negatives as RGB files not to lose any information - then you keep one layer only in PhotoShop. This was very well explained on Markus Hartel's website some years ago.
As discussed in some other threads, Tri-X isn't a genuine 400 film any longer. It must be exposed at 250 if you want to develop it in standard compensating developers like D76 or X-Tol.
Bottom line : for scanning 35mm films, a dedicated film scanner is a must-have. Even the modest Minolta Dual Scan II (real 2820 dpi resolution and excellent Dmax) which can be bought for less than $100 off the second hand market nowadays will blow away any Epson flatbed, even the V750 etc. The only caveat of this remarkable machine (the same with the Dual Scan III and Dual Scan IV) is that the sensor is slightly smaller than 24x36 so you can't create the "HCB black borders" when scanning. If those borders are mandatory you must go for a Nikon Coolscan IV or V and file down the SA-21 film carrier window a bit, which is very easy to do.
charjohncarter
Veteran
Highway 61, thanks for this write up. I do almost exactly what you suggest except for the dedicated film scanner. Will read Markus Hartel's website if I can find it.
willie_901
Veteran
It's All About Information Content
It's All About Information Content
This is correct.
Information content increases from zero (at total under exposure) until complete overexposure. At that point, the only thing you know is there is no useful information in the overexposed regions.
The scanner's analog dynamic range is a completely different factor affecting the information content of the final digital file. The DR could be limited by the scanner's hardware or it might be limited by operator technique.
Film digitization requires two measurements: one involves photo-sensitive chemical reactions; the second involves converting visible light energy into analog DC voltages followed by digitizing those voltages.
Both benefit when optimized to maximize information content for the data.
It's All About Information Content
This is correct.
Information content increases from zero (at total under exposure) until complete overexposure. At that point, the only thing you know is there is no useful information in the overexposed regions.
The scanner's analog dynamic range is a completely different factor affecting the information content of the final digital file. The DR could be limited by the scanner's hardware or it might be limited by operator technique.
Film digitization requires two measurements: one involves photo-sensitive chemical reactions; the second involves converting visible light energy into analog DC voltages followed by digitizing those voltages.
Both benefit when optimized to maximize information content for the data.
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