Friday, December 5, 2008


I don’t know if you have noticed on TV, but ads for some new flat screen TV’s are now touting mind boggling figures for contrast-ratio of a million to one. Can anyone see a million to one? Or does it matter in the definition of a talking head’s picture on screen to what the pundit is saying about his crystal ball into the future of Barack Obama’s governance after January 20? Technical specification have been a boon to imaginative marketing mavens ever since cars were described as having horsepower, and the race goes on for who can concoct the most outlandish claims.

Of course there is Consumer’s Report with their labs to measure products objectively and then provide a subjective assessment that is almost as fanciful-- one of my favorite laughs when I sat in an editorial office and got a copy of Consumer’s Report camera issue on my desk, was their “best buy pick” was always some ungainly model that frequently ended up in the dustbin of the history of obsolete products made by companies that soon failed. Does anyone remember Miranda?

Seriously, besides technical specifications that abuse and misuse the trust of people, they also contribute to a misunderstanding of how products in the real world function. This morning I responded to a reader’s comment that a particular scanner he was considering had a “poor” dynamic range specification. The scanner in question does have a dynamic range greater than the density range of any normal film image there is to scan, but it is not as high as some scanners that are 4.0 and greater offered in the recent past. What is not realized is in this case maybe bigger isn’t better, in fact just the opposite. if a scanner’s dynamic range is significantly greater than the density range of the film images being scanned each raw scan will create a file space with a significant amount of space that is blank with no image information at one or both ends of the density scale. This will require that the image data that is present will have to be expanded by interpolation to fill the colorspace of the output file (a Levels optimization correction in Photoshop), to be useful for quality output of a print for instance.

This pressure to sell scanners featuring ever higher dynamic range specifications, also has a potential downside when the scanner is used to scan color negatives which have a much lower density range compared to reversal color transparencies by as much as 2/3rds. Thus the scan data has but a small amount of image information in raw scan output, as would be evident in a Levels histogram, which to fit the output color space must be expanded dramatically in software processing by the scanner driver. Ideally a scanner with just half the dynamic range of contemporary film scanners would probably reproduce better image quality output images if used just for scanning negatives.

Of course consumers do want information upon which they can base a decision as to what to buy. But when specifications are technical and cannot be practically verified by the user, there is a lack of reality regulation and some specifications become not much more than hype, and it actually is a contest of which company exercises the most hubris to inflate figures more than the next. The LCD display market has been particularly obfuscating using all kinds of technical jargon and inflated figures while beyond the measured size are essentially meaningless, the exception being the high-priced professional graphics products most stores don’t even stock. But at the same time if you want to find out if an LCD brand has separate independent controls for contrast, brightness and backlight adjustment or if it has discrete white point color temperature settings, that information is missing or confused with the jargon and hype. So a potential purchaser often cannot determine if a consumer home/office LCD display can or cannot be effectively calibrated and profiled for doing digital photography image processing.

Here unfortunately we live in a free-market world that would not flourish if fettered by regulation it is claimed, but should sellers of technical products not be kept honest and candid about their claims?

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