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photoblogography - Just some stuff about photography

Real World Sharpening

in Book Reviews , Wednesday, August 30, 2006

imagesharpening.jpg When I first saw that Bruce Fraser had written a new book on image sharpening with Adobe Photoshop, I had two thoughts - first, how does he resolve the potential conflict arising from his involvement with PixelGenius and the PhotoKit Sharpener product, and second, do we really need a complete book on sharpening ? Well, he deals with the first issue openly and quickly, and he completely avoids plugging PhotoKit in the book (actually, I think he could have allowed himself a few mentions!). The book is essentially tools-agnostic, which is great (although obviously it deals with Photoshop's particular implementations). The second question is answered by the book: I don't know if we needed a book on sharpening, but we needed this one. Bruce Fraser is a simply wonderful educator. He can transform extremely arcane topics into page-turners (as with his "Real World Color Management", and he has a sense of narrative, which some may think is unnecessary in technical books, but in fact transforms them, just like any other kind of written word. He also writes in a friendly and highly approachable style, quite unlike the tiresome "zany comedy" deployed by, say, Scott Kelby (maybe being treated like idiots appeals to Americans, I don't know, but it iritates me...). Obviously style is nothing without content, but that isn't an issue here. I don't think there is anything in this book that I hadn't already somehow heard of, but there are plenty of things I never really understood. Reading this book suddenly makes the use of the expert controls in Photoshop sharpening - and PhotoKit, of course, and indeed other software - much, much clearer. The discussion on evaluation sharpening on-screen is particularly illuminating. The other thing I really like is the equal handling of film and digital - whilst many would have ignored film altogether, Fraser gives it considerable attention. Actually I really would like to see some discussion on the use of Photokit, particularly as it applies to capture sharpening. The book strongly recommends masking at the capture sharpening stage, or at least avoiding sharpening areas of flat contrast (such as sky), and I'd be interested to know how much of this is "packaged" into Photokit. I'm sure it wouldn't upset Adobe too much, after all, you still need Photoshop. And on the other hand, various 3rd party noise reduction tools are mentioned. The only downsides to this book are that (a) I'm supposed to be moving house at the moment and I shouldn't be getting distracted with this stuff, and (b) I want to go back and resharpen every image in my collection, and (c) I have to question if my current habit of global capture sharpening in RAW Developer is such a good idea after all. If you want to get the best out of your photos, this book is very highly recommended.
 

Whistling in the wind

in General Rants , Tuesday, August 29, 2006

Well, the speculation is ramping up on what Olympus will or will not deliver at Photokina. I don't particularly care, as I can't afford it anyway. But it will be interesting to see if Olympus are still interested in anything approaching the pro DSLR market. There's a lot of talk about what MUST be provided and how "Oly" (or "OLY" for the more Neanderthal) has to do X, Y, or Z, or else the writer will "leave". Ho hum. Since the various fora represent probably around 1%, if that, of Olympus DSLR owners, and are by defintion dominated by geeks and nerds, rather than photographers (yes, thanks, I do appreciate I'm in the same boat), the relevance of all this venting is, frankly, low. Not as low as the relevance of this column, however, and that isn't going to stop me listing, for the benefit of my 3 readers, what I would not give up. These are the basic features which convinced me to buy an E-1, and which I expect as a baseline in whatever comes to replace it, if anything:
  • Clear, bright (for a DSLR), 100% coverage viewfinder (short of top end Canikons, nothing else on the market has this)
  • Interchangeable finder screens
  • Weatherproof
  • Dust shaker
  • Superb ergonomics
  • Quiet shutter / mirror
And these are the improvements I would like to see, in something close to the same body:
  • Better autofocus. Much better. More AF points, more sensitive, and more reactive
  • Larger screen, with instant histogram display
  • Permanent ISO display in viewfinder - even better: user configurable viewfinder display
  • Better high ISO performance: 1 stop would be ok, 2 better. (i.e, current ISO 400 quality at ISO 1600)
  • More resolution: ability to print at A3+ at 240dpi without too much upsizing, so around 10Mpix, but 8Mpix would be ok.
And if I don't get everything I DEMAND, then I'M LEAVING!
 

Conflicting opinions

in Photography , Monday, August 21, 2006

In the last couple of days, two widely conflicting opinions have been published on the Leica zoom lens which ships with the new Panasonic Lumix L1 camera. Vincent Luc, writing in Réponses Photo, is disappointed with it. Not that it is bad, but he finds that the sharpness and contrast are simply not up to the expectations associated with Leica. He does, however, add that there might be some scope for improving matters in post-processing. Now, Vincent Luc is no idiot, and the review is well considered and comprehensive, nothing like the recyled PR and datasheets that most web sites pass off as "reviews". One website which certainly does not fit that in category, however, is The Luminous Landscape. Michael Reichmann, in his L1 review, has a radically different view:

"Having taken many hundreds of frames with this lens during my week in Iceland I can tell you that this is one first-rate optic. No formal tests are needed to let me know that this lens is sharp, contrasty, and quite free of any serious aberrations – at least those visible without conducting a formal test suite".

Going back to the post processing issue, it is interesting to pick up on a recent post by Colin Jago, discussion in this case the sharpness in general of Olympus E-1 images (let's just imagine that the E-1 has the fully compatible Leica zoom attached). He observes:

"(...) one of the things that you always have to bear in mind is that you only have 5 megapixels to play with. Further, these are quite soft megapixels (the anti-aliasing filter). Whilst I think that properly sharpened native resolution prints from the E1 can be fantastic, (...)".

So what is everybody actually talking about here ? First, whilst I suspect that the Vincent Luc's results are based on JPGs, I'm sure Michael's and Colin's are based on RAW. The almost diametrically opposed opinions of the lens sharpness and contrast are striking. But... is Michael talking about the results as seen (and maybe optimised) in Adobe Lightroom?

Both Colin and Vincent Luc talk about recovering sharpness lost by the anti-aliasing filter, and this where I really start to lose the plot. An AA filter is a low pass filter, usually with an abrut cutoff. It is designed to prevent the sensor from recording high frequencies which it cannot unambiguously resolve. I don't want to go into a long discussion on filtering here, but in this type of setup essentially any data blocked by the filter is gone and no amount of post-processing can bring it back. Frequencies near the cutoff frequency will be attenuated. In photography terms, this translates as an irrecoverable loss of fine detail, or more accurately, a limit on the level of fine detail that can be captured. This is obviously extremely simplistic, and people could - and do - drone on for hours about it.

Sharpening in software can give a percerption of a more detailed image, by subtle enhancement of the actual detail. But doesn't make the lens sharper or more contrasty.

The approach of evaluating the camera-lens pair using DxO's system seems to be the only consistent way to review digital systems. But when the reviewer is looking at photographic output, as the three I quote here are, then the software plays an equally important part, and should be explicitly declared.

>Perhaps we should start to talk about lenses in a different way, saying for example that on camera X, processing with software Y, lens Z does not limit resolution or inhibit contrast. Then maybe it becomes easier to understand how two highly competent reviewers can draw such different conclusions.


So, is the Leica lens a dog or a gem?
 

Lightroom Podcasts

in General Rants , Wednesday, August 16, 2006

I've been an avid listener to George Jardine's Lightroom podcasts, and whilst I'm still not really convinced by Lightroom, I have to say I really enjoy the podcasts. Jardine come across as a really excellent product manager, keeping the conceptualistation, expectation management and focus of the project under tight control, whilst sounding relaxed and enthusiastic. I'm sure it is an exciting job, and one that I'd grab in a millisecond given half the chance, but it must also be extremely arduous and stressful. The downside of growing up in public like Lightroom is is that the whole world can see every mis-step, and also expectations start to go out of control. Every potential customer expects the product to be tailored exactly how they want it, and will scream loudly when it doesn't. And of course, in the unlikely event of Lightroom failing, the product manager will be the first in front of the wall. Unlike some, George Jardine doesn't try to oversell Lightroom. In fact, he hardly tries to sell it all. He puts it on display, provides a lot of background, builds up a nice ambience, and lets it speak for itself. Certainly, after every podcast, I'm keen to start it up again and have another look – although since I'm usually listening during my commuting on train, tram & foot, I can't, really. When I do, I'm still not convinced that the overall concept (shared by Apple Aperture) works for me, and I still find the user interface overwhelming and often obscure. But the interesting thing is, after each podcast, I want to love it. I guess I'll get hooked sooner or later.
 

Panasonic Lumix L1 previewed

The new Panasonic L1 has been previewed by Reponses Photo (excellent French print magazine). As they say, on paper, a collaboration between the makers of the Lumix compacts, Leica and Olymous should be something special. But they're disappointed. Whilst they are quite enthusiastic about the general concept, the build quality, and the degree of control, there are a series of downsides.
  • The "Live View" feature simply isn't as useful as the version on the Olympus E-330, mainly because the screen is fixed. However, unlike on the E-330, apparently you can use auto-focus without restrictions.
  • The optical viewfinder is dark and cramped, and the physical design, which sticks out 1cm at the back, is simply asking to be damaged. They reckon that the eyecup will be lost within days.
  • The handling is a bit clumsy, as balance, with the kit lens attached, is front heavy. Which exacerbates the viewfinder design issue.
  • The "Leica" kit lens is interesting, but the aperture ring is awkward to use, it is very heavy, and whilst its performance is good, it does not meet the expectations associated with Leica.
  • The camera is very expensive, twice the price of the E-330, which they consider to be a better camera on balance.
  • Still stuck with that rather tired old Olympus AF module
  • Did I mention too expensive ?
On the plus side:
  • Panasonic provide Silkypix RAW software rather than reinvent the wheel (poorly), although arguably it would have been better to also use DNG format.
  • The lens isn't all bad: as RP points out, this is the first stabilized zoom lens from any company with a decent maximum aperture.
  • They describe the flash design as "genius": it has two positions, the first pointing 45 degrees upwards for bounce flash.
  • The image quality is reported to be good up to 800 ISO.
  • The camera also includes 3:2 and 16:9 ratio setiings, and this is where Panasonic's implementation of Live View adds an extra dimension. But of course these sacrifice resolution.
At half the price, well, maybe. But at 2000 Euros, though, it looks like Panasonic have screwed up this one. Pity.
 
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