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Saturday, 21 February 2009

Comments

Personally I can do 99% of my photography, professional or fun with my DLux4. It is technically up for the challenge. The only reason I carry my A900 on paid jobs is because it makes me LOOK like a pro. For the types of photography that I do, I do not need super telephoto, macro, creamy bokeh, or iso25800. Maybe because I shot with a Pentax ME super and a 50mm for 20 years before I bought my first digital camera and zoom lens that I feel that I don't need any of those things. At normal sized prints and web viewing, most clients and people simply cannot tell the difference between the DLux4 and the A900.

Yes the change is huge, and it's worth standing back every now and again to appreciate it. We have far too many level comparisons between this year's competitors (who's the winner?) and too little assessment of how much is enough: perhaps all the current models have ample resolution (say) for your purposes, in which case you should ignore that and think about other things.

I'm re-processing some scanned slides from the last big project shot on film, a 3-month trip in 2003, and they aren't great in the technical ways we've grown used to judging. But the pictures seldom care.

However, most of them are in sunlight, or bright overcast, and all the other visual impressions of that trip, at night and indoors, went unrecorded. I feel this is the biggest direction of progress for "serious" cameras: the expansion of lighting conditions under which we can shoot easily. And these awful conditions are worth shooting under, as low light is often interesting light.

The other big direction of progress is towards smaller size and less intrusion. In good light, pocket cameras are now in many ways better than film SLRs were, and a lot easier to carry around every day. Which means more time with your visual system turned on and looking at the world, which surely means better pictures.

I like SWAG. Scientific wild ass guess. Mainly because it is easier to pronounce. Good article

Oh Ctein, I really do love you, in a not-really kind of way.
I've been telling customers for quite a while that they need to remember how ridiculously good those new, cheap digicams are. I've been thinking about doing a test like that, shooting the same scene with ISO 800 or 400 color neg, a P&S and a Nikon D60 or something. And then printing the pictures out to show.
Why haven't I? Have to admit, I'm a bit scared of doing it, because I have a feeling that my darling, the film, will be in the third place, and not by a small margin.

The exasperation when a customer refuses to buy an Olympus E-420 because "it's useless over ISO 800", or a Canon G10 for the same reason, is quite overwhelming. Especially when I know they have been shooting film before.

After 60 years of shooting Kodachrome (Original, II, and 25), and printing with everything from Printon to Dye Transfer to Cibachrome, I don't have any of the problems you mention.
I am, however, always irritated by the posts on nearly every forum that I follow, by people who have obviously never been within shouting distance of a wet darkroom. Even many "pros" seem to expect PhD performance from their cameras and printers.
I'm not sure if your analysis also applies to B&W -- probably not yet.

With respect to dynamic range forget about "digital"...

In the "film era" the best location portrait photographers (wedding and otherwise) used negative film (10+ stops). Skin tones look significantly more flattering with the contrast dialed down.

Further, black and white photographers throughout much of the past century had access to 10+ stops. Though this dynamic range is not required to make a good image, it can, at times, be vital to a great image.


As for:

"Sure, the digital characteristic curve has that ugly brick wall it runs into in the highlights, but that's a matter of nailing down one's metering technique (something many photographers haven't internalized, it's true)."

Do some "high-key" portrait photography for a while and see how quickly your notions about highlight shoulders and dynamic range change.

Photographers had this capability before digital and are only now starting to get it back with the latest generations of cameras!

(Ctein, were you a "slide film only" snob? If so, I hate to inform you that negative film was used for years by "great" professionals.)

Oops...

I didn't read carefully. Sorry.

I see that your discussion was more about photographers being dissatisfied with 12 stops and 6400 ISO.

Clearly, this "dissatisfaction" is a result of the fact that most people have seen digital go from 7 stops to 12 stops, acceptable ISO400 to good ISO6400, and 6 megapixel to 24 megapixel in about 5 years. (The situation is more surprising for people "in the digital game" before about 2002.)

For someone who dreams of capturing night scenes hand-held, 12 stops at ISO6400 is "barely adequate"!

I'm playing devil's advocate above.

Personally, I am satisfied with 9 stops and ISO3200 - both of which I had before digital came along (the ISO3200 was B&W).

It's the combination of having widely published metrics on specifications like dynamic range and noise and the human desire to always want what's readily available +1. When I grew up a 20" TV was considered luxurious, now there are official calculators that tell you that 42" flat screen plasma is the "ideal" size for your living room. Seriously, who comes up with this stuff?

Please forgive two posts, but I had another thought. With 12 or more stops of dynamic range in digital, you could expose in the center and then have plenty of room to roll off the highlights and shadows in post-processing. This might be a way to a more film-like look.

I'm not sure if I can fully relate to all that is being said about dynamic range (I agree, a bad and meaningless name in the world of photography). I've known for longer than I care to admit that film could not record the range of what I see and that enlarging paper even less than that. Ink jet paper does not capture the full luminance of the image, but with so much viewing done on computer monitors I wonder if that is why photographers are shouting for more range? Another question--how many of users of DSLRs own a hand held meter let alone having used one? Have too many people grown up with in-camera exposure determination? I do agree that digital photography represents a major shift in photography.

As Ctein eloquently points out in his wonderful book Post Exposure*, the central technical problem of photography is attractively and believably translating the vast dynamic range of the real world into the much smaller range of film (or, nowadays, a digital sensor); and then compressing it further yet, down to the even more limited dynamic range provided by printing paper. That's what Ansel Adams' zone system was all about: systematically exposing, developing and printing to deliberately control how that tonal range is distributed in the final print. Digital methods provide far more precise control, but the principles haven't changed. You're still working to cram that potentially huge real-world dynamic range into the much smaller shoebox of printing paper.

I started out shooting K64 slide film, so for me even first generation digital SLR's provided at least one more stop of dynamic range at the capture stage. Each generation since has improved on this; and now using HDR techniques there's almost no limit to the dynamic range you can get into a digital file.

But we're still sharply limited by the far, far smaller dynamic range provided by printing paper. That's still the 'rate limiting step'. If anything, the wider dynamic range captured by newer devices can make it more difficult to produce a beautiful interpretive print that doesn't look weird or artificial. It's an enjoyable challenge.

*Anyone who prints, either darkroom or digital, really should get a copy of Post Exposure. Ctein's remarkably lucid description of the interaction between human perception and printing materials is a revelation.

Good article! Yes, we are spoiled these days. And only argue over and over about how much more spoiled we want to be.

.... the funny thing is that regardless of technical specs, we've always seen the full range of quality in photographic imagery from the rare gem to the useless pile. All the way back to the 19th century (and ISO-equivalent of what? 10?) no limitation of process or materials stood in the way of photographic excellence or, conversely, were the cause of mediocrity.

Dear Wilhelm,

Yes, I'm pegging my reference point to the reasonably-skilled printers (both darkroom and digital). You and I are way, way beyond reasonably skilled. It wouldn't be realistic to use us as the standards by which typically-good prints are made.

My comments apply to both black-and-white and color negative films, but different issues show up. Purely from the film side of things, color negative films actually have a better exposure range than black-and-white films (unless you make the black-and-white films jump through some really odd hoops that really screw up their curves). But it's easier to print longer subject luminance ranges from black-and-white films, because a little modification of the development and an appropriate grade of paper gets you a lot more range. Whereas in color, to accomplish the same thing requires contrast control masking, which very few darkroom printers ever learned (probably about the same percentage as black-and-white printers who actually learned how to properly use compensating developers and split filter printing). Plus, trying to print a really long subject luminance range in color risks looking a lot weirder than doing the same thing in black and white because of the mismatch you end up getting between luminance values and hue and chroma values in the print.

The reality is that most good darkroom printers, regardless of their chosen medium, rarely if ever placed a 10 stop luminance range in their prints. We elite are a different matter.


~ pax \ Ctein
[ Please excuse any word-salad. MacSpeech in training! ]
======================================
-- Ctein's Online Gallery http://ctein.com 
-- Digital Restorations http://photo-repair.com 
======================================

Dear Jeff,

Oh my, you really don't know your friendly neighborhood photo columnist, do you? Since you are new to the party, read these two columns and then you can decide what kind of a medium snob I am (hint: I'm the farthest thing from it).

The Photo-Fetishist Leaque
http://tinyurl.com/ynr62a

Lazy? Does Not Compute!
http://tinyurl.com/5ayovj

For the record, 99+% of my professional work has been done on medium format color negative film. Over my 40 years doing photography, I have exposed approximately 40 slides per year. That's frames of film, not rolls! It doesn't include film tests for the magazine articles I've written. Add another 20 per year for that. But if it weren't for those magazine articles, I wouldn't even be exposing 40 frames for myself; it's just the manufacturers send me damn bricks of the stuff and I hate having it go to waste. What I can't give away I'll sometimes use on a lark.

The photographs don't even look too bad... for slides (he said snobbishly). [vbg]

See my posting to Wilhelm in this thread. I am entirely familiar with what kind of subject luminance range black-and-white and color negative films can capture. I can also tell you as solid fact that unless you were doing contrast control masking, you were never getting close to a 10 stop subject luminance range in your darkroom prints.

Interestingly enough, there were a couple of really good portrait photographers using slide film. Until I saw their work, I wouldn't have believed it was even possible to do good portrait work that way. Dave LeClaire Studios in Michigan, one of the premiere dye transfer portrait studios, dealt with an extremely elite clientele. He worked entirely with slide film and his prints were excellent. Amazing.

That said, I can easily come up with photographic situations where the typical characteristic curve shape for digital makes it a much less desirable medium than negative film, for the same dynamic range. But in common and typical professional use, those situations are not the norm, and what I'm writing my column about is the normal range of professional/serious amateur expectations.

I know your 9 stops and ISO 3200 black-and-white film. Love that stuff myself. Honestly, though, the signal-to-noise ratio sucks compared to good (not even the best) digital. And still photographer's expectations keep rising. It's remarkable... so I remarked on it [ smile ].


~ pax \ Ctein
[ Please excuse any word-salad. MacSpeech in training! ]
======================================
-- Ctein's Online Gallery http://ctein.com 
-- Digital Restorations http://photo-repair.com 
======================================

Dear DC,

What Geoff said. Fine printing has always been and will always be about translating a real-world subject luminance range and tonal placement into the much more limited density range of available in a print.

There's actually not much difference between the usable density range in a digital print and a darkroom print. Oh sure, the D-max in the darkroom print is higher, but the shoulder on the paper curve is sufficiently long that you can't actually use that density in any real print. You can only get to within 90-95% of that. From a practical point of view, darkroom papers are only a little better than digital.

There's the additional problem that traditional materials and printing methods have substantial toes and shoulders on their characteristic curves. That makes it difficult to render good shadow tonal separation in a print. Even with a slightly more limited density range, it's a lot easier to do this digitally.

I haven't used a handheld meter since I was 16. Every camera I've had since had one built in. Good enough for me. But I get your point, which is that most photographers don't learn how to meter correctly for their materials. They never have, and they probably never will. Fact of life, I'm sorry to say. They used to rely on the toe and shoulder of film to keep them out of trouble. Now they're discovering that doesn't work any longer. I think they'll adapt.


~ pax \ Ctein
[ Please excuse any word-salad. MacSpeech in training! ]
======================================
-- Ctein's Online Gallery http://ctein.com 
-- Digital Restorations http://photo-repair.com 
======================================

Some interesting comments here. I shoot regularly with a 1Ds3 (or occasionally 5D), a Zeiss Ikon using black and white or colour neg film and a ricoh GX100. All offer something different, although I suspect that if Zeiss introduced a high resolution full frame digital Ikon I'd swap in a moment.In practice, nothing I shoot with can get near the 1Ds3 in any objective measure. But, I still like shooting film sometimes. For digital black and white I am increasingly finding ways to improve the highlight rendition with careful exposure processing - so apart from the the grain it's a bit of a draw as far as I'm concerned and I can concentrate on what I want from the image.

Just as an afterthought, I've just printed a monochrome shot for a client that was exposed at the equivalent of iso8000 on the 1Ds3 and at 10 by 7 it is noise free - with no luminance reduction in Lightroom. I think that's incredible and feel fortunate to have such a range of tools available.

Mike

"...how many of users of DSLRs own a hand held meter let alone having used one?"

FWIW, I don't think I've ever even seen a hand held meter except in the local camera store. I don't understand why it would be a negative.

I know some people love them and are enamored with them, but I don't really see the point. The meter in my camera works just fine, even if I'm shooting in manual, and has several modes for checking various parts of the scene.

I am now using a Canon 5D MarkII. I am just astounded and humbled by what I have and what I am now able to do. I can only say that I am so very glad that before I croak or become too incompetent to handle the equipment and the software commensurate with the inherent quality of the files produced that I have, perhaps, some time to explore all over again the world with this marvel and the equally marvelous software that has allowed me to invent and reinvent my dreams. I built my first enlarger using an ancient bellows camera from the early 1920s and rebuilt an Argus C3 from the blue mould that had fully engulfed its archaic body. I was fourteen years old. I never looked back once I discovered photography and though I strayed into other arts for much of my life and really lost the thread with film and paper due to the rural problems and a lack of iron free water to wash my prints. With the advent of digital cameras I returned and along with me I note the plethora of magazines on the news stands that had been a forlorn place with but one or two periodicals to document photo for a long time certainly meant that I was not alone in this. I thought once that photography had died a slow languid death by small cuts..the huge increase in film costs really limited young people as I once was to explore the medium but now..look at the world. Everyone seems interested in this great art form or at least aspires to it. The manufacturers who survived the changeover to electronics are brilliant and there are many cameras worthy of the greatest minds and eyes of the artist today. A kid can get a camera that would make a Leica owner blush in embarrassment at the technical superiority of many of these little things and with the advent of high resolution wide latitude DSLRs..my God!..perfection ( well, nearly) is at hand...and most importantly, one can actually save enough gold to buy one and not just dream of it. Again..I am a happy artist deep in the pigments of light and the inks of printing. Film is now along with bichromate gum printing, a historic page with a new future upon us. Long live the visual tradition and welcome to all those who have discovered what some of our lives have visited for half a century or more.

Ctein,

1) With respect to my "slide snob" comment: I assume you realized I was being facetious and that I was not questioning your knowledge of ANY aspect of photography (I know what I don't know...and compared to the regular posters on TOP, I don't know photography).
2) With respect to "Oh my, you really don't know your friendly neighborhood photo columnist, do you?"...
You are absolutely correct. I have seen your site and read most (if not all) articles you have posted here. From the little slices of you that I have witnessed, I assumed (yeah, I know...) that portraiture is not the first thing that comes to your mind when you think about photography (and write photo articles - although I would gamble that you have done far more SIGNIFICANT portraiture work than I ever will).
3) With respect to "Interestingly enough, there were a couple of really good portrait photographers using slide film."...
One of the most beautiful available light portraits I have ever taken was a 6x4.5 using a "low contrast" color slide film. I know great portrait work can be done with slide film if the lighting is right. I have a hard time believing that someone could have survived using exclusively slide film for non-studio portraiture.
4) With respect to "the signal-to-noise ratio sucks compared to good (not even the best) digital."...
Most film companies knew they were stuck with the "noise" and spent tremendous effort to make it look pleasing. I think many of them succeeded. In some cases I think the "noise" can add to an image.
5) With respect to D C Rieger's comment about hand-held meters...
I think most 35mm shooters gave them up when SLRs started offering "spot metering" in the 80s/90s. I would gamble that most photographers reading TOP know when to "trust" their camera's matrix metering and when not to (as well as how to nail "down one's metering technique" for highlights).

I recall a comment from a week or two ago that one user 'couldn't possibly get a good 24x36" print from a 5dmII. Leaving aside the strong differences of opinion on this camera, I remember wondering to myself exactly how many people ever got a good 24x36" print from 35mm film, even with Velvia or Provia or Ektar 25?

Yup. I'm with you on this one.

I love to see higher ISO performance and better dynamic range, when I can afford it, but I see that learning to be a better photographer is more important than either of those.

They do allow me to take pictures where my skills let me down. Or they'd let me do HDR without the tools, I cannot seem to figure those out anyway. Skill trumps many a feature, any day.

We're not completely alone, there are many, many serious photographers taking awesome photos using 'old' cameras without complaining. Just look at the http://www.flickr.com/groups/strobist/pool/>Strobist pool on Flickr. And I rarely join in on the vocal boards that demand higher dynamic range, there's no point in it.

"...exactly how many people ever got a good 24x36" print from 35mm film?"

Mark,
Depends what you mean. If you mean a 24x36 print that was good as 24x36 prints from 35mm went, then quite a few. If you mean a 24x36 print that was a good print--well, it never happened in the whole history of photography.

Mike

Dear Jeff,

In the world of passionless plaintext, facetiousness is not readily apparent. Take my word for it, people have asserted much weirder things about me in all seriousness.

Fortunately, *I* don't take it seriously.

I don't know that David did all his portraiture using slide films, but I do know that's all that he used for the highest-and clients, the ones who were getting dye transfer prints. His studio only made dyes from slides. I've seen some outdoor large-group portraits that I have no idea how he made. Doesn't seem possible to control the lighting under those circumstances. I'm guessing sorcery...

I doubt that I've done more significant portraiture than you. Certainly I've done my share of it, but it's not something that my muse gets at all excited about, so I'd be surprised if any of it is noteworthy (except for the occasional photograph of historical interest, like Dick Feynman sporting a mustache). If it's something that you're even halfway interested in, I bet your portrait work is a lot better than mine.

And in other noteworthy (or not) trends, unless I've misfiled some negatives it's been over two years since I exposed a roll of film. I'm still not ready to admit I've given the stuff up. I'm even getting some samples of the new Ektar 100 120 to test.


~ pax \ Ctein
[ Please excuse any word-salad. MacSpeech in training! ]
======================================
-- Ctein's Online Gallery http://ctein.com 
-- Digital Restorations http://photo-repair.com 
======================================

Add me to the list of people who have never owned or used a hand held meter. I got into photography in the early 1980s, and the center weighted meter in my first camera always worked fine for me because I took the time to learn its characteristics and limitations. Now matrix metering makes things even easier, but one still has to learn what it can and can't do. I have used a hand held flash meter, but now even that is unnecessary for me with a digital dslr. One less piece of equipment to hold onto, keep track of, and keep supplied with batteries is a good thing.

I like to shoot live music in dimly lit bars for fun. I had given up on high ISO 35mm film as useless long before digital made the scene. Possibly in 15 years of almost daily darkroom work I didn't learn a thing, but to my eye the prints I'm getting out of my recently obsolete 5D at ISO 3200 (even pushed beyond) look amazing in comparison to any high ISO (400+) medium format film I ever used (stuff that was available in the 90s).

Ctein, I'm a little troubled by the comparison of the Fuji S100fs photo with the NPZ800 photo. Digicam photos are almost always at some stage algorithmically massaged to reduce noise. Has the NPZ800 photo benefited from comparable treatment? I can improve the NPZ800 photo considerably with about a minute's work in Neat Image.

I agree that everything is wonderful now. However, I recently bought a Panasonic G1 and have been playing with it for several days, and when my daughter had my second grandchild yesterday I took it with me to the hospital when I visited her. This was just a thoughtless picking-up-of-a-camera that'd I'd been using, and I took a dozen bracketed exposures when I got there, and what I found when I got home is that I should have picked up my D3, which was sitting on the same table as the G1. The pictures are fine, and everything, but I'm distracted by the noise on my daughter's face and in the darker areas of the shots (the hospital room was quite dim and I shot at ISO 800, and at 800 the G1 is noisy and the D3 isn't. So, while everything is wonderful, some things are more wonderful than others, and that's why people keep screaming for more and more -- they see the extra wonderfulness of the top-end machines.

JC

Love the article, and would like to add;

Current technology can easily deal with the "Digital Blow Highlight" issue without resorting to increased dynamic range.

Reduce exposure and then introduce some non linearity such as gamma adjust.

I suspect this is what Canon does with their "Highlight Priority Mode".

It is also similar to what the non linear attributes of film.

Dear Latent,

Once again, everyone repeat after Mike and me:

"Illustrations are not meant to prove a point, only to illustrate it."

Please write this in your workbooks. It'll be on the final exam and count for 10% of your grade.

[smile]

The illustrations fairly represent the difference in grain/noise characteristics of the two media sans any end-user manipulations.

pax / Ctein

Dear folks,

At the risk of wandering off-topic (yeah, right, like I'm so careful never to do that)...

Would there be any number of readers who'd be interested in a column that talks about how film manufacturers have 'chemically massaged' their latent images to reduce film grain/noise?

Not saying when I'll get around to writing it, just wonderin' if it's worth adding to the queue.

And a tip'o'the' Ctein hat to Latent for putting the idea in my head!

pax / Ctein

Dear Matt,

Thanks for the data point! You didn't say if you're working B&W or color. B&W film's been pretty much unchanged, since; color neg film has picked up about another stop in speed.That is, the ISO 800 medium format stuff looks as good ISO 400 did a decade earlier.

pax / Ctein

I wonder if a lot of the wishing for a greater "dynamic range" is actually simply wishing for greater tonal discrimination, either in the shadows, or in the highlights. Will not more bits (14, 16 etc) solve this problem in the future? It seems to me that the difficulties in this regard have to do with inadequate computing power (at the rapid fire rates that modern DSLRs are designed for) and perhaps the widespread user base of software geared towards 12 bit raw or even jpeg inhibits this particular area of improvement.

I'm at the very ends of my technical expertise (quite possibly, beyond my technical expertise) in this speculation, but won't 16 or 18 bit pictures with the existing levels of dynamic range suffice for the kinds of highlight control discussed above in the post on high-key portraits?

I can't feeling that there is a lot being overlooked regarding the strengths of both media. By way of comparison consider the brush strokes of say Johannes Vermeer (1632-1675) and painter Robert Bateman(1930-) . In the former it is what is not illustrated that gives meaning to the image. In Bateman's for example sake the power comes from a reflection of light off the side of a hair. - Higher dynamic range? I would say yes and the fact that pigments and paint technology have improved exponentially since the days of Vermeer.

By the same token even a lith print shot of the right subject in the right light can convey every bit as much information as a HDR image. Is the additional detail really that important to convey what the photographer has to say or is it just the wow factor of the technology. I suspect in this instance it is the latter and we are totally enamored with what this technology can deliver, it also sells cameras.
Quite frankly most HDR images leave me a tad cold it takes a very good operator with a great deal of aesthetic sensitivity and restraint to produce quality with HDR. It takes time for any new technology produce its best. Anybody remember digital processing prior to the PSD file? I am somewhat amused by current popular reaction to state of the art digital, it has taken the best part of 350 years to turn Vermeer's camera obscura into a pinhole digital DSLR!
By the way it seems Vermeer was just as enamored with his technologically advanced camera obscura as we seem to be with the digital camera.
Which just goes to prove contrary to popular expression its what is done, not the way it is achieved.

I agree with you. Cameras are amazing today. That being said, all the 800 speed film I've ever shot looks nowhere near that bad. Even stuff that was minilab developed and scanned. I'd post a link to a picture, but I don't know if I can in the comments...

Does anyone think, great, 12 stops to play with, I'll endeavour to show that stupendous dynamic range in this picture, but then say 'Why ?', and actually see it as a somewhat futile exercise in trying to make a dull picture more interesting or a good picture quite dull ?
Just wundrin.
Aren't the pictorial qualities of a photograph more interesting in terms of the relationship between tones and colours than the representation of, say, a (virtually) full dynamic range. Is the latter self defeating, since our eyesight adjusts to levels of light sequentially, it doesn't seem to me to be important to capture an enormous 'dynamic range', I don't think it is what we see as a whole only what it is possible to see by intense scrutiny, for a given scene. This is why, to me, a HDR or this new Fuji treated style, looks more like fantasy art than 'what the world looks like photographed'- I'd be more comfortable with an illustration of that view than a photo. Huge dynamic range, in terms of my personal aesthetic, is a tool not an every day desire. I would rather digital technology address the ability to use optical sharpness rather than having to use an algorithm that can put a kind of 'digital screen' over a picture (forgive me for lacking the eloquence more often found in these pages).
In short, dynamic range capabilities have been acheived (I'll regret saying that !). I'm happy looking out my bay window at the trees and birds with slightly 'darkened' interior walls framing that view, I fix my gaze on a painting on a wall and the previously darkened interior 'lightens' as my eyes adjust - EV range around 8 stops. Out of my pictures encompassing this scene my prefered ones emphasise the outer or inner light, the one with the 'full' range displayed just doesn't look as pleasing, neither aspect of that picture holds interest. Who needs 12 or 14 stops, who can display them successfully, I think we should be told.

Let me add my compliments to Ctein for an insightful and thought-provoking article. More generally, thanks to Mike and all of the contributors here for making this one of the most interesting and informative places on the web.

I do have one technical question for Ctein, and this relates to the methodology for determining dynamic range. Using the Nikon D3x as the current state-of-the-art example, the DxO site reports an amazing dynamic range of 13.7. In its recent test, dpReview reports a maximum usable range for the camera of 9.3EV at ISO 3200, and 8.4EV at the base ISO of 100.

There would seem to be different methods used by each site in reaching their conclusions. Implicitly, it would appear that Ctein, in citing the DxO data, accepts their higher dynamic range conclusions as valid. I'm hoping that he can provide some clarity as to the reasons behind the apparent discrepancy without overloading my technically-challenged brain. Thanks!

Mani - The current bit limits at 12 or 14 aren't because of a computing power limit, per se (although it is more expensive for the circuitry to handle more). The limits are actually there because of noise, e.g. the amount of precision you get out of reading the sensor is limited by random noise. For whatever value is read off of the sensor, you can't get any more precise unless the noise is lower than the precision you're trying to acheive.

For instance, if you could take a current 12-bit SLR and take a 14-bit sensor reading off of the sensor, you'd have the same effect as just adding two completely random bits. This is because the two new bits would create smaller gradations within cameras built-in range. These small gradations would be smaller than the pixel value jumps that already exist due to noise, so they'd be swamped by the noise.

On the other end of the scale, a much larger dynamic range at the top could be a use for more bits as well, in recording much brighter tones. Either way you need a lower noise floor or increased dynamic range to make use of more bits.

Dear Tim,

The illustrations above are so enlarged on your monitor that they're like pieces of 50" x 70" prints.

So, you've got some 4 by 6 FOOT prints from your ISO 800 35mm negs? If so, get your nose as close to them as you do to your computer screen and let us know what you see.

What makes you think a minilab's print is an accurate and unaltered portrayal of the film's characteristics?! Do you know what happens to the 'data stream' between development and printout?

See my comment to Latent Image, above.

pax / Ctein

An HDR image, when printed, should look no different than any other print as the DR of the print is the limiting factor. Just as a colour negative provides more flexibility (and fallibility), so too does the HDR image.

Digital users have gained much, but have thrown the baby out with the bathwater. I always enlarge my 35mm images to 1.5m (that’s meters) and see no grain; why- I use slides and project them. I have a full frame viewfinder (0.8x magnification) for only $500; why- I use a second-hand “new” Canon F-1N.

I’ve just read Ansel Adams’s book “The Print”. On the one hand the advantages of the digital darkroom, over the wet one, are clear to see- so much can be done so more easily in Photoshop. However, towards the end he talks about how he masks and presents his prints- a long complex and consuming process. This is just so alien to most enthusiast photographers who are paying thousands for their cameras and doing nothing with the resultant image. Back in 35mm days most photographers simply took their films down to the pharmacy to get them developed and printed- colour killed off home printing for the vast majority. If your camera was good you might get slightly larger prints, and you always had the negative for future enlargements, but that was it unless you used slides. Now with digital users shooting off thousands of images (of increasing megabytes) they don’t even do that. You can’t even have a “slide show” for these megapixel monsters as even $50,000 digital projector projects only 2Mb. images (and has a little coloured wheel inside). The use of the 35mm SLR by the press was a major reason for SLRs popularity. The move to digital made complete sense for them, but the serious amateur has not been served so well by the digital revolution.

Mike Jones,
I think you get the "most assumptions per word" award. Not many of which I agree with, personally. Maybe that's just me.

Mike

P.S. I think you mean "mats" rather than "masks."

Dear Chaz,

Oh sure, ask me the simple ones [g]. I'll try to keep the answer relatively simple (hah!).

First, why do I trust the DxO exposure range results? There are two reasons. One is that I like their experimental protocol (I am sensitive to the merits and deficiencies of an experimental setup like Mike is to the image quality of lenses). The second is that in the one case where I tested the exposure range of a camera that they later reported on (DDB's Nikon D200), I came up with an exposure range that was within half a stop of what they reported (11-11.5 stops):

Finepix S100fs review (http://tinyurl.com/62m9bc)

That's a remarkable level of agreement, considering that our experimental methods were entirely different.

Second, you're not looking at quite the right data on the dpreview site. Check out these two URLs; the first explains their testing procedures and the second shows the results for the Nikon D3X. This is the data that is closest to what DxO is measuring:

http://blog.dpreview.com/editorial/2009/01/raw-headroom.html

http://www.dpreview.com/reviews/nikond3x/page21.asp

Here dpreview reports better than an 11 stop range. In fact, if you look at the plot showing maximum headroom ("ACR best 14 bit"), they run off the graph at the shadow end of the scale. The photographs of the step tablets at the bottom show the red bars indicating the absolute limits of the exposure range are within one step at the end of the step tablets. Essentially, they've run out of range in their instrument!

I don't like dpreview's experimental setup as well as DxO's. I'm not saying the former is bad, just not as good. The big problem with using their approach to measuring extreme exposure ranges is that it is very, very difficult to get the level of flare and scattered light low enough to keep it from filling in the shadows. What we used to call "veiling flare" in film photography. When you're trying to measure 10,000:1 luminance ranges, it is a serious experimental issue. My approach (and DxO's) is to fill the frame with uniform illumination and vary the amount of light the sensor receives. While this creates problems controlling the amount of light that gets to the sensor, it's a readily measurable and correctable error. Without an ability to position a photometer sensor in the film/sensor plane of the camera, it is more difficult to confirm that you have flare and light scattering under sufficient control.

Third, are DxO's results BETTER than dpreview's? Not really; they are just different and they're measuring somewhat different things. What DxO is giving you is information analogous to what you would have gotten from a film manufacturers' technical datasheet-- how the film performs in laboratory tests, exclusive of as many lens and camera variables as you can eliminate. Take that same film out photographing and you'll get different results. The data is for comparison purposes to other films tested on to the same methods, not an absolute measure of field performance.

I find those manufacturers data sheets to be very useful. I know how to combine that data with lens and camera data to get useful real-world information. At the same time, dpreview's tests are closer to real-world, which means they're confounded by real-world variations, but they may be more like the conditions you'd be working under (…or not).

At the extreme of the dichotomy between real-world versus datasheet, we have this:

www.clarkvision.com/imagedetail/dynamicrange2/index.html

This is a truly awful experiment in its design and execution. The results don't tell you a damn thing about the inherent performance characteristics of either the films or camera sensor involved. They're not even close to correct. BUT... this is very much how a real-world photographer would make a real-world photograph. So the results probably are representative of what would happen if you just went out and randomly made photographs. BTW, look through the website, and you'll see that Roger is a damn good photographer, really excellent. Just because he didn't design a good scientific experiment doesn't mean he can't make great photographs under demanding and technical conditions. It's apples and oranges.

In closing, please note that this is not an invitation for people to start arguing about whether they like or don't like DxO's data or protocols (or like them better than dpreview's). Okay? it's been done to death, and it's boring. Unless you honest-to-God have something NEW to say on the subject, that wasn't said in the umpteen previous threads about DxO (read the old articles BEFORE posting, not after), please consider that topic closed? Thanks!


~ pax \ Ctein
[ Please excuse any word-salad. MacSpeech in training! ]
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-- Ctein's Online Gallery http://ctein.com 
-- Digital Restorations http://photo-repair.com 
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You, Mike (Johnston) are certainly not the user I'm referring to- that's why I read your blog. Yes, a lot of unsupported statements.

Ctein-

That really wasn't so bad- I never felt in any danger that my head would explode.

Seriously, many thanks for a lucid explanation. I'm embarrassed to admit that my look at the dpreview dynamic range data was so casual that I didn't even realize that it was in-camera .jpgs (rather than 'best' raw files) that were being measured.

My confusion began because I was somewhat skeptical of the huge dynamic ranges being quoted at DxO-- even my humble Pentax K10D is said to have a dynamic range of 11.6. While I'm very fond of this camera, my subjective 'feel' of it*s output would have led me to guess that the range was considerably lower.

Your answer not only addressed the discrepancy in the reported numbers, but also explained how real world results may vary from the test numbers. Again, thanks for a first-class article and your subsequent explanation.

Late and way behind the curve on this thread.

But a short story: I was feeling pretty good about myself using a Sekonic spot meter and a 4x5 in the Southwest one day, going through all the correct motions and getting the mother of all shots, when I suddenly realized that my exposure was the perfect sunny 16.

For any of you who saw me collapse to the ground that day at Canyonlands and laugh like a hyeana, I apologize.

Anyway, I try to have low expectations about technology and high expectations about my own abilities, and I kind of hope that they don't converge, except in the rare print.


This is probably a bit late of a reply, but I wasn't talking about the enlargements. I was talking about the tiny web resolution 'full frame' film pic you posted. In print equivalent terms, thats probably about 1"x1.3".

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