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Memories of detail


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<p>Larry,</p>

<p>I called it a stupid thread because people were being stupid. BUT, I liked the thread and so posted something people could really get their teeth into, it seems to have worked. It is funny, we all get so used to what we work with and are familiar with, we don't look too far out of the box sometimes. I seem to be unusual in that I have, and use, MF film and high quality FF DSLR's, I don't "love" either of them. I don't "need" more quality than my dslr can give me often enough to justify a MF digital setup.</p>

<p>Mauro,<br>

I'd be happy to, what do you specifically see as needing help in the digital image? I'll have a play :-).</p>

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<p>Mauro,</p>

<p>The crop is from a sensor area just under 2.3mm X 1.5mm, or just under 3.45mm square. Less than 1/250 of the sensors real estate, or 0.4%, sorry I got the decimal place in the wrong column earlier!</p>

<p>On my monitor it replicates at 230mm X 153mm, for 35,190mm square, an effective 10,200 times area enlargement, or a 100 times linear enlargement. So were you to print it out at this resolution you would be looking at a 3.6m X 2.4m print, or 142 inch X 94 inch, 12 feet X 8 feet.</p>

<p>I upsampled from 360 X 240 pixels to 700 x 467 (I think) so linear upsample of less than 2. With this resolution and no upsample you could print to 6 feet X 4 feet. With vastly improved resolution and no upsample you can print to 36" X 24", which strangely enough is my largest standard print size.</p>

<p>Hope this helps, Scott.</p>

<p>P.S. I might just take you up on a couple of slide scans next time i'm in the USA.</p>

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<p>Scott, B&W conversions are difficult from digital because the data lost from the Bayer and AA filters cannot be recovered (that is in addition to the sensor's limitations).<br>

Here the crops represent a similar proportion of the entire frame, but as you pointed out, it is a much larger area in absolute terms.</p><div>00XKi5-282919684.thumb.jpg.397a86c08076f1df621c2f9afd106963.jpg</div>

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Mauro, I never replaced my MF camera with a digital camera. I used them side by side. Sometimes MF was better.

Sometimes digital was better. Performance depends on lighting and other conditions since the two technologies render

images differently.

 

When I replaced my MF film camera it was with the 4x5 film camera that I still shoot regularly. No detail has ever been

lost. Nor have I ever lost a shot that film would have missed but digital could have captured easily, as is sometimes the

case.

 

I'll post my revised example this evening.

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<p><em>Scott, B&W conversions are difficult from digital because the data lost from the Bayer and AA filters cannot be recovered (that is in addition to the sensor's limitations).</em></p>

<p>The commonly held belief that Bayer filters cause a loss of detail relative to color film has been obliterated by observation. If Bayer did this then film would have higher low contrast and color detail than digital. This is clearly not the case when comparing within the same format. At 12 MP DSLRs start to resolve more low contrast and color detail (see the D2x sample at Les Sarile's site). At 18 MP and greater DSLRs exhibit considerably more low contrast and color detail, the very detail Bayer should destroy in theory. DSLRs resolve very close to their Nyquist limit pretty much regardless of brand or model. A careful comparison against Foveon sensors shows a small loss of detail, but clearly Bayer is much more efficient and effective that many people estimate from theory alone.</p>

<p>Relative to B&W film Bayer is not throwing away information, it is preserving information that B&W film by nature throws away. Try applying a yellow or deep red filter to a B&W film image after the shot.</p>

<p>AA filters cause a loss of sharpness more than anything else, which can be restored in post. I'm unconvinced there's any real loss of detail having looked at images produced by a DSLR with its AA filter removed, but I can't confirm or deny that without having one to test against a resolution target.</p>

<p>No, the reason why B&W conversions from digital can be challenging has nothing to do with resolution, Bayer, or AA filters, and everything to do with tonality. Years were spent perfecting the tonal curve of B&W film, and years of study and information are available on development which photographers can use to customize this curve in the lab. A straight conversion of a digital color image is typically flat and muddy by comparison. It takes some work, and some experience with classic B&W, to mimic the tonal response of classic B&W films.</p>

<p>A lot of the digital B&W work I see does not have that classic look regardless of how it stands on its own. (It may be excellent work, but the tonality still betrays it as different.) It is certainly possible to mimic that tonal response however. The best advice I can give on this point is to spend some time shooting both digital and B&W side by side, scene by scene. Every where you go take two SLRs, and everything you shoot, shoot both. As you develop and print the B&W (ideally yourself in a darkroom) develop and print the digital files to match the B&W. You'll get a solid feel for the differences between them, and how to get the digital to mimic the B&W tonality. Also, I think Silver Efex Pro is easier to use in this respect than the tools built into PS.</p>

<p>The upside with digital is that once you have the eye and technique needed to mimic the look, you can consistently get that look from any scene. My experience with B&W film is that it either looks great or looks terrible depending on how well the film and development is matched to the scene. Digital RAW gives you a pretty neutral capture of a scene regardless of the tonality in the scene. But then you have a host of tools in the RAW converter and in PS (levels, Shadows & Highlights, LCE, curves, etc.) with which to reshape the image curve to match the scene. You also can apply color filtration after the shot, a notable advantage in my book. You don't have to take notes and manage this before seeing the image on film, something Zone system adherents are religious about but which isn't always practical with roll film. You can just do it with image in hand.</p>

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<p>Daniel,</p>

<p>I agree. On average, I see more terrible B&W film work than good. Unfortunately, many people don't expose correctly for the shadows and compensate for highlights to suit scans. Thus, what we end up with is a combination of poor exposure, poor processing, and then poor scanning getting the worst of the worst.....blocked up shadows, clipped highlights and acentuated grain.</p>

<p>I used a mountain of TP when I used to hypersensitize it for astronomical photography. I started using it for some pictoral work but never really enjoyed the tonality of it. I prefered the look of Ilford FP4 and HP5.....TP looked stark in Technidol. I love the lack of grain in 6x7, but prefered the look of HP5.</p>

<p>Which brings me to my last point. I thought, back then, that I would like to have as little grain as possible in print. What I found was that with a 6x7 neg, even with FP4, there was minimal grain in a 24x30. In fact, when I look at scans from those old negs, I actually prefer them with that little bit of grain....it adds a bit of texture to the final image, giving the appearance of even greater detail. Therin lay my issue....while TP had more real detail in print, the FP4 looked like it had as much because of this fine texture.</p>

<p>Now, most of us add a bit of noise to images in prep for print. Adding this noise to a 5D2 image during B&W conversion in Silver Efex showed me that there was little more in the scans from my RB67 than the 5D2....at 16x20....and sometimes even 20x30. A bit of noise in the B&W really makes it appear more detailed. </p>

<p>I used a Pentax k20D a lot in Death Valley last year. I've made some 24x36 prints on HM Photorag 308 that were processed in Silver Efex. These looked superb.....despite the poor showing at 100% on screen.</p>

<p>While I love film for a lot of work, sometimes it doesn't matter. For this shot of clay in the dunes, at 24x36, I can see grains of sand with no problem. Processed in Silver Efex with the HP5 look if I recall. I reduced the grain somewhat to match what a 6x7 HP5 scan would look like.</p>

<p><img src="http://2.bp.blogspot.com/_mX5HKyiQAwQ/TDNDG1a9SGI/AAAAAAAAAGU/tCugD4nz784/s400/Deat+Valley+Dunes.jpg" alt="" /></p>

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<p>Mauro,</p>

<p>Given that your crop represents an area of film equal to 15.7mm sq and mine is from a sensor area of 3.45mm sq I think it is pretty amazing that the digital is anywhere near the MF film.</p>

<p>So for your consideration, here is a 15.7mm sq crop from the digital sensor. This now levels the playing field, we are comparing like for like. High end FF digital SLR sensor at 100iso and Tech Pan at 25iso.</p>

<p>I have done no processing to this crop, it is downsized slightly and converted in Save to Web and Devices but all with auto settings. No sharpening.</p><div>00XKuL-283043584.jpg.658411c69dd32382dc3ed3b2a4abbe65.jpg</div>

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