Interesting post. Some thoughts:

> You know how digi-photos, no matter how dazzling, often look a little tight and flat? One of the reasons for this is that their exposure latitude is narrow.

Kinda sorta. Digital has much narrower exposure latitude than print film, but about the same as or slightly more than colour slide film which is what most pros (except wedding & portrait specialists) shot for years. So that in itself isn't it.

More of an issue is that digital has no "shoulder" - that is, the light sensitivity is more of a straight line than an s-curve. With film, the amount of detail in blown highlights or dark shadows tails off smoothly; with digital, highlights just blow with no gentle tail-off.

There are a couple of interesting approaches to fixing this. One is software, as you mention - I've heard that Kodak's new shadow retrieval stuff is excellent. Fuji have also announced a new SLR, the S3, which has sort of 6MP resolution but that consists of two 6MP grids, one of big pixels that are good for low light, one of small ones that are less likely to blow out intense highlights. They reckon that by reading the big ones, but then seeing if they can get a reading from the small ones in areas where the big ones are blown out (or something like that) they can get a dynamic range more like print film. Fuji's digital SLRs so far have been very good indeed, so it will be interesting to see how this works out.

I've also read a theory that, because of the way different colour sensors are laid out on most current imaging chips, red is more likely to blow out, or has less resolution, than other colours. This is said to produce the effect where digital images have less colour contrast and general "snap" and feeling of depth than good film images, and is again said to be not *too* hard to fix in Photoshop. (http://www.outbackphoto.com/dp_essentials/dp_essentials_05/essay.html)

>The Kodak guy said that he and his colleagues think that a digiphoto would need 13-16 million pixels to match a tiptop film image.

This is about right for the very finest-grained 35mm films. You can see film grain clearly in images scanned at or above about 3000 dpi, so that says a piece of 35mm has an effective resolution in the region of 3000 x 45000 dpi =~ 13.5 "megagrains". Note that there are a couple of 35mm style digital SLRs with this resolution, and there are professional studio cameras over 20 megapixels (also over $20k)

That's for the very finest grained slow fims, shot on a tripod through a good lens - which, however, isn't how 99.9% of photographs are taken. In particular, digital holds up much better than film for shooting at very high ISO in low light. Very fast film has huge and obvious grain and very poor colour fidelity; digital produces a lot of noise when shot at 1600 ISO or above, but that's much easier to fix in software than blotchy grain and nasty colours. (Kodak's digital SLRs are notoriously weak in this area, but Nikon and Canon are excellent)

A lot of people also seem to think that the absence of noise in good (SLR, low ISO) 6MP digital images more than compensates for the slightly lower absolute resolution (2000 x 3000 for 6MP versus 3000 x 4500 for 50 to 100 ISO film)

>He compared the current state of digi-photography to the early days of music CDs, when the sound they delivered -- while brilliant and clear -- was also cold and grating.

Sounds about right to me. Glenn Reynolds had an interesting piece a while back where he predicted that, as with tube gear in music and recording, the "warm look" of analog will be a cult in a few years.
(http://www.instapundit.com/archives/012990.php)

I'm thinking about selling my Hasselblad to buy a digital SLR, but I haven't quite been able to bring myself to do it just yet. I will never sell my Nikon FM2.

I also completely agree with your previous post about horrible digicam ergonomics. There's an interesting new Leica/Panasonic effort that sounds as if it addresses a lot of these issues, but it's ridiculously expensive for a digicam ($1500 to $1800). My thoughts on that here:
(http://www.alanlittle.org/weblog/Leica3.html)

Posted by: Alan Little on March 15, 2004 4:08 AM

A more significant contributor to the lack of "depth" in consumer sigicams is the extremely small size of the sensor - typically 2/3" or smaller. This makes for virtually infinite depth of focus, and very boring photos. I have a Canon DSLR, the 10D, which while not full-frame 35mm, has a large enough sensor to get some good shallow focus with fast lenses.

Also, my 10D has a 6MP sensor - and to my eye, the pics I take with it are better than anything I was ever able to achieve with film. IMHO, as always...

Posted by: jimbo on March 15, 2004 11:47 AM

I have yet to purchase a digital, although I am chomping at the bit. I just now have gotten on friendlier terms with my Canon 35mm, but I must say, I love having control over my shots. After reading these comments, I am still not sure what camera to buy to go "digital". Oh well. Looks like waiting is still not a bad option!

Posted by: Cowtown Pattie on March 15, 2004 12:12 PM

If you already have a Canon with a few lenses you can't really go wrong with the Digital Rebel. It's pricy - about $1000 - but it takes all your old lenses, operates pretty much like your old 35mm, and gives much, much better results than any digicam...

Posted by: jimbo on March 15, 2004 1:16 PM

Jimbo,

very good point, although I sort of assumed the Kodak guy might have been referring to SLRs too. I have heard that criticism directed even at SLR images.

Posted by: Alan Little on March 15, 2004 1:29 PM

Thanks to Alan and Jimbo for explanations. My Kodak engineer wasn't being that clear. He was muttering stuff about "curves" too, but I had no idea what he meant.

Interesting wrinkle where digi-stuff is concerned is movie imagery. It seems that part of what makes on-film movie imagery so creamy (assuming good print, good projection, etc) and deep isn't just that each frame has a ton of information. It's also that each frame's grain pattern is different than every other frame's. So when they flip by superfast, the illusion of total continuity is created. With a movie digi-image (at least digitally projected too), the grid pattern of pixels is the same for every frame. The in-between places never get creamed over, if you'll forgive the phrasing.

As a consequence, the digital movie image seems thin and watery -- fine as information, works great in a blockbuster, but lousy where poetic and sensual qualities are concerned. So cinematographers and directors try to compensate by making the image bright, crisp and poppin'. They often cut faster too, because individual shots just can't hold the interest the way that single film shots can. So out the window go depth and poetry; in the window come jitter, pop, and effects. For these and other reasons, I think we might as well think of the result as a different art form entirely. Some other people point to the change from silents to sound and think I'm being overdramatic about it.

I wonder, in any case, how many pixels a movie image needs in order to overcome the rigid-grid problem. Any hunches?

One more question: why aren't the digi-camera people building sensors the size of 35 mm frames? Are they locked into the current size? Did they not anticipate how soap-opera-y the small sensors would digi-imagery look? Is there some engineering challenge that makes manufacturing 35mm-size sensors impossible?

Posted by: Michael Blowhard on March 15, 2004 3:15 PM

Pattie -- Actually I think now's a great time to go digital. Prices have settled down, models have standardized a bit. My $199 new Kodak shoots 3 megapixels (tiptop snapshot quality, and even enough to let you do a little cropping), has autofocus and a 3X optical zoom, couldn't be easier to use (it's easier than the point and shoot film cameras I used to own), and the battery life, which used to be a prob with digicams, is now pretty good. All for 199 bucks -- what fun. Things will only get better and cheaper in the future, but wel consumers always seem to have to live with that ...

Posted by: Michael Blowhard on March 15, 2004 3:19 PM

The grid-versus-irregular-grain thing sounds interesting, and regarding how fine the grid would need to be: I was discussing this with Michael Jennings a while back. Can't remember what the answer was, and it depends how big the screen is and how far away you're sitting. If you take as a rule of thumb that 300 dpi print on paper is pretty much dotless to the naked eye at normal viewing distances, then a pixel on a screen X feet across, viewed from Y feet away, needs to look as small as a 1/300th of an inch dot looks a foot or two away. I have no idea what the answer to that calculation actually is, though, and it's late. Exercise for the reader.

>why aren't the digi-camera people building sensors the size of 35 mm frames?

They are - Kodak and Canon have high end cameras with 35mm sized sensors and 11 to 14 megapixels, and there are pro studio cameras that are even bigger. They are very expensive indeed ($8k for the Canon 1Ds, $20k+ for the state of the art studio wonders), because the manufacturing yields go down (exponentially? - again, can't be bothered to do the math right now) as you try to produce a bigger piece of silicon without a single faulty pixel. As far as I'm aware maufacturing yields are the only real obstacle.

Well, that and the cost of the other kit you need to go with them - you need $1000+ pro lenses to come anywhere near the resolution that the big sensors are capable of - prices quoted above are without lenses - and those lenses won't fall in price because they need precision machining and assembly that are far harder to do at larger sizes than for tiny p&s digicam lenses.

Posted by: Alan Little on March 15, 2004 5:27 PM

I'm mourning the loss of my digital camera, which fell into the Seine this weekend (too much confit and Beaujolais). Your information about cameras is timely indeed -- thank you. I have to get myself properly digitized in the European manner and I'm overwhelmed by the options that I must weigh. It's a bit intimidating in French, too, I must say, but I shall prevail.

Posted by: Maureen on March 16, 2004 1:41 PM

Old-fashioned film cameras have just three essential controls that are simple and quick to use. Many digital point-and-shoots are loaded with obscure icons and complex menus. However, digicam designs will be improved, as other commenters have noted.

All images end up digital, but with film cameras there is a high cost in time or money for scanning. OTOH there is no question that processed film, and in particular B&W negatives, lasts a long time with little care, while long-term digital file storage remains uncertain. OTOH digicams can make hundreds of exposures which can be viewed immediately. OTOH there is not yet a digital version of a compact rangefinder camera. Your equipment preference will be a function of which set of tradeoffs is most important for you.

Posted by: Jonathan on March 17, 2004 2:44 AM






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