Digital Capture & Standard LF Lenses

[Struan Gray]

Given a choice between marketing a 10 megapixel back that does things correctly - i.e. oversamples by a factor of three or so and then digitally dithers, bandlimits and downsizes - or a 90 megapixel back that 'resolves' more, albeit at the expense of some aliasing, I can't think of a photographic supplier or user that won't take the second option. Astronomers, microscopists and the CIA, all of whom know what true resolution is, might prefer the former, but the photographic industry beyond the factory doors of the optics houses has simultaneously fetished 'sharpness' while failing to understand what it really is.

A bit of aliasing isn't all bad. In fact, a lot of people prefer the edge effects you get in non-periodic images. But when it bites, it bites hard. I have seen some truly hideous photographs of textiles with fine-scale structure such as Thai silk. There again, I'm a probe microscopist, and not getting fooled by aliased 'atoms' is part of the job description.

Glenn, I too would be interested in seeing your results, although my wallet tells me that in my case the information will remain purely theoretical :-)

[Glenn Kroeger]

Struan is of course correct... and the marketing folks would never miss a chance to use a larger number to characterize any product, since larger must be better. OTOH the poor buyer who has to feed the beast with CF cards would end up preferring somewhat smaller sized files!

[Chad Jarvis]

I stand corrected, but seeing how other companies and marketing efforts truly create inferior products to satisfy some segment of the market or another, I'm dubious of any claim that a certain product is "better" because it's engineered for a different task. Like I said, I stand corrected. Apparently Rodenstock's digital lenses really do "produce better images then traditional optics". Question, though...why not make traditional optics better?

[Bob Salomon]

Chad,

Yes the digital lenses do produce better images. However they also need to be used at larger openings then a large format lens and will be in diffraction at f16 and 22. Additionally they cover smaller circles. The GR series cover a 70mm circle. The Apo Digital cover a 105 to a 150mm circle (depending on the focal length).

If you want to use a smaller circle and a larger aperture we don't need to make LF lenses better you can just use the digital ones instead.

As a comparison we can send a CD if you are interested that has comparison product shots of a detailed original between a digital Rodenstock and a similar non digital one. I will send out one if someone wants to upload it. I can not send out several.

[Bob Salomon]

"GR"

Sorry, HR series not GR.

I have been writing 26 new press releases for PMA later this month and got caught in too much typing.

No, nothing new for Rodenstock but new stuff from Linhof and Wista at the show.