taking a High dynamic range picture

If you send me twenty rolls of Tri-X, the forum will forgive you. :)

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Originally Posted by Steven L

Oh man, I really opened up a can of worms. I do appologise for that. It was not my intention. I guess I'll have to get some books to get the proper information and practice, practice, practice.

All those years of digital photography has blinded me. Forgive me, I have sinned. ;)
(I say that with a joke, but it's actually the truth.)

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If I have to send Tri-x every time I F#@K up, I'd better buy in bulk.
I'm going to do without forgiveness, but try to be a good guy from now on.

going to pick up a roll or two of Tri-x today and shoot some b/w pictures.

Steven, some of us like worms. ;)

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Originally Posted by E. von Hoegh

Film is high dynamic range, just as it is. You can't print it though, because the paper has a shorter range than film. If you want to experiment with the line drawing look, try whatever lith or microfilm emulsions are available. You might like solarisation, too.

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Paper doesn't take x stops of dynamic range on the film from the original scene, it responds to a density range, lower contrast neg can print more dynamic range using standard printing.

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Originally Posted by keithwms

This is super easy with b&w film. Just use POTA developer. 20 stops of range. No muss no fuss.

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I believe what the OP is looking for is excessive local contrast.

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Originally Posted by chuck94022

Steven, with all respect, you do not understand HDR. (Forgive me this digital digression, APUGers, but it is important here.) HDR takes *selected portions* of two digital images, chosen by a complex algorithm, and combines them into a single image. It does *not* just combine two images.

HDR is not a digital version of an analog technique. HDR is a computationally intensive digital only process. Its purpose is to capture and *interpret* a very wide luminance (brightness) range using cameras and display technologies that do not naturally present such a range. This is complicated stuff in the digital world. But we're not in the digital world here, we're in the (sounds of angels singing) analog world.

Analog has a leg up here. Film (except slide film) can capture quite a wide luminance range. With development "tricks" (different chemicals, different development times, and different ways of "sloshing" the film in the chemistry), one can achieve a number of effects that are now *simulated* with digital tools like Photoshop (contrast, accutance, curves, etc.).

During the printing phase, other analog techniques come to play that are also now simulated in Photoshop (dodging and burning, and unsharp masking, for example).

There are many, many techniques you can do in the analog world to add an artistic touch to your work. In addition to doing your own development, you might eventually want to explore alternative processes for printing (like platinum printing, which doesn't require a darkroom and produces stunning results).

Good luck with your journey. Before trying to make analog "like digital", study a bit, and perhaps you will realize that those digital folks are still trying to catch up to the wonders of the analog world.

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HDR combines multiple images into one, they are blended together, does not take portions of images. Exposure Fusion takes portions of differently exposed images of different areas and assembles those different areas into one image, like masking two different images together.

You can display "HDR" just fine, it will just be low contrast (also dynamic range has nothing to do with bits, and digital camera 'LDR' images have more dynamic range than the output device, eg one camera may have 5 stops, and another 10 stops, both display within the 0-255 range). What you are talking about is tone mapping, a HDR image displayed normally with 0-255 range will have low contrast areas, eg: foreground dynamic range may be 3 stops, sky may be 3 stops, but difference between the darkest area of the foreground and brightest area of the sky (total DR) may be 16 stops just as an example, displayed normally foreground would be black to dark grey, and sky would be light grey to white, making a dull image.

With (seemless) tone mapping, the idea is to display that foreground at black to light or middle grey, and the sky from dark grey to white, or with even more excessive contrast, the ground at a complete range of black to white, and sky also complete range of black to white without clipping of either end. Like masking, or well balance with a grad ND.

Basically, to extend the contrast of local areas to near the contrast of the entire image, or more excessive match it. So that the image is high contrast (LDR) instead of dull and low contrast (HDR). Also to match more what the eye sees, as the eye is self-masking and suffers chemical exhaustion to both high luma and saturated chroma, so you see each area at the same time with good contrast.



eg: I may take a beautiful sunset shot on colour neg film not using filters and relying on it's DR to capture everything that looks pale and low contrast compared to slide film I've used reverse grad ND on, and assumed slide looks better because it's slide, and colour neg is just pale with no saturation, but then I go back and shoot it again with a reverse grad ND on the colour neg to lower the contrast, by lowering the contrast I am raising the contrast of the image when the black corresponds with the darkest portion of the scene, and white with the brightest, on both.

If you want the artificial HDR look, the way to do that would be a combination of careful exposure (so you get all the information you need on the film) and contrast masking. A contrast mask is made by exposing a piece of bw film in register with the original to make a precise dodging mask that is printed in register with the original neg to hold back the shadows and allow for extra exposure to get more detail into the highlights.

Historic printing-out processes like albumen printing are self-masking in this way and don't require a separate contrast reduction mask to achieve this effect.

I think this is an example of an artificial hdr look 1150 years ago
http://www.metmuseum.org/toah/works-of-art/1976.646

Athiril, your post is so much more accurate than mine. Thanks for sharing your knowledge of this. I'm not terribly experienced in HDR, I was just interpreting what I understand based on my user level experience.

Sorry APUGers if my post was misleading in any way.

One suggestion, Athiril: with all due respect, your writing will be much easier to understand if you reduce the length of your sentences. While your content is correct, it is difficult to get to the essence of your point when so many concepts are pulled together into one sentence. In other words, your writing has High Dynamic Range, and at least in my case, my brain has Low Dynamic Range. :D (My father was a journalist. He drilled into me at a very young age never to write sentences longer than 21 words. I don't always succeed...)

Separately, totally agree with David G. on careful exposure and contrast masking. It seems there are also a number of simple things that could be done (with black and white anyway) using dodging/burning. It seems that one could dodge/burn incorporating colored gels on VC paper to affect local contrast too. I've never tried this. Would it work?