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View Full Version : digital back with detail and clarity superior to 8X10 transparancy



Neal Shields
4-Dec-2001, 19:58
Better Light's latest ad in View Camera magazine for their digital back claims " superior detail and clarity to an 8X10 transparancy"

This would seem to be an objectively measureable statement. Put me in the doubt ing Thomas catagory.

Jorge Gasteazoro
4-Dec-2001, 20:50
I think they have never seen an 8x10 transparency, probably the reason for the statement.

Michael S. Briggs
4-Dec-2001, 21:09
I am not sure how to quantitatively compare "clarity". Comparing resolution isn't easy because of the different nature of digital vs film: fixed grids vs randomly placed silver. This makes resolution fall off differently as the resolution limit is approached.

Their website has a comparison of their digital scanning backs: http://www.betterlight.com/pages/super_specs.html. The higest resolution is the Super8k, http://www.betterlight.com/pages/prod_super8k.html, at an uninterpolated 8000 x 10660 pixels or at Enhanced Resolution(SM) of 12000 x 15990 pixels. They are somewhat vague about what Enhanced Resolution is, claiming that it is better than interpolation. It apparently involves interpolation since they use the word "uninterpolated" for the lesser resolution.

The claim about detail is repeated on the web site. The Super6K, which has less resolution, is described "produces the ultimate in image quality, subject detail and tonal range. It can deliver results superior to 8 x 10 inch transparency film in a fraction of the time, ..". However, they don't mean exposure time, because that's 100 seconds, or 200 seconds for the Super8k. Obviously this is for still objects.

Let's take their best numbers, accepting their claim that "Enhanced Resolution" delivers real information: 12000 x 15990 pixels. Spreading these pixels over 8x10 inches, one gets 60 pixels per mm. Film and lens resolution are generally measured in lines pairs per mm. One needs at least 2 pixels per line pair, but realistically more than 2 pixels since this assumes perfect alignment of the pixels and lines. So 60 pixels per mm is at most 30 line pairs per mm and more realistically something like 10 or 15 line pairs per mm. The film/lens combination can easily deliver information finer than 15 lines pairs per mm. It seems that the ad copy writer has gotten carried away.

The digital industry would probably do better if there wasn't so much hype. I tend to ignore all of the claims because so many are highly exaggerated. These backs would save money for a camera that is used many hours a day in product photography, and the resolution is more than adequate for magazine reproduction.

Ellis Vener
4-Dec-2001, 22:00
Better light is one of the better firms about hype. The downside of their backs is that they are scanning backs, not single shot, in short terms, theis means the CCD (or wnat ever) moves across the frame pixel leight by pixel height . Exposures get measured in minutes. The back they seem to be claiming this for is the Super 8K which produces a 549MB file.

Jorge, these guys actually do know what an 8x10 transparency looks like.

If you wan to know more about their product go here: Better Light Home Page (http://www.betterlight.com/home_page.html) and then read through the specs and the FAQs, especially for the Super 8K.

Rob Tucher
5-Dec-2001, 18:07
I know little enough about the subject to have just attended a seminar on high-end digital photography presented by Jack Reznicki, a NY child photographer, and hosted by Leaf (single-shot backs). Similar claims were made by the company, and Mr. Reznicki said that fully 70% of his clients ask for digital these days, even though he was being very open and honest about whatever he felt even though Leaf reps were there. Where digital seems to shine is in extreme enlargement, like for outdoor displays, because grain from any size chrome looked to become apparent much more quickly than pixels. It was impressive, and I am a dyed-in-the-wool b&w,larger-the-format -the-better sort of guy, like most of us here. But the actual comparisons are interpretations by the non-photographer sorts who design, manufacture, and market these things to photographers. It's not that they are wrong or misleading or anything like that. They know their stuff. We're just from two different worlds.