Schneider/Phase 40-80mm LS Zoom

[jerome_m]

I think that the reason you got no answer is because this is not how lenses are characterised. They don't "outresolve" or "underresolve" backs, they have a given contrast level for a given line-pairs value.

FWIW, this zoom is not a first in medium format. Hasselblad, for example, has had a 35-90 zoom for a while now. It is not inferior to the primes it replaces. I would expect Schneider Kreuznach to be able to manufacture a MF zoom that is just as good.

[Doug Peterson]

I would have thought that one of the dealer's might have stepped in by now and answered this? i.e. 'Will my digital back out-resolve the lens or will the lens out-resolve my digital back' is a pretty fundamental question for anyone planning to drop $9k on this bit of glass. For that price, the answer had better be the latter.

I've not yet answered because good dealers wait and do their own testing rather than rely on charts, numbers, or manufacturer claims. Our demo unit has not arrived yet, and so I have not been able to shoot with it and therefore I cannot report based on my own findings.

I don't really care or value much of what a lens designer says their target line-pairs-per-[whatever] or micron density was. I care about what I see when I take some challenging images.

[buckshot]

@jerome_m

Ok, how many lp/mm can this lens resolve?

Rodenstock quote the pixel size their lenses are good to because this makes a lot more sense in the digital age than lp/mm.

@Doug

No problem - makes perfect sense - but at the same time P1 must know the answer to the question, so why not mention it in the press release / specs they publish? They should take a leaf out of R/S's book.

Maybe you could ask them and post the reply here?

[jerome_m]

Ok, how many lp/mm can this lens resolve?

At what contrast level? That question only makes sense if you give a contrast level. (And: no, I do not know, as technical data has not been published).

Rodenstock quote the pixel size their lenses are good to because this makes a lot more sense in the digital age than lp/mm.

If they really do that, they lose a lot of credibility in my books. I agree that this would be a very convenient figure for photographers. The problem is that lenses do not work that way.

[buckshot]

Quoting the pixel size down to which your lens performs is a useful short hand (as opposed to contrast vs spatial frequency) way for telling the guy in the street, 'you know what, the detail that this lens can resolve is a worthy match for your digital back.' I'd rather be out shooting pictures than pouring over MTF charts - I just need to know that for $9k this lens is supposed to sing, not just hum out of tune.

To quote Schneider-Kreuznach: "The pixel size and pitch of a CCD array would clearly determine the necessary performance of a lens for use with this array".

Well, they know the pixel size and pitch of P1's flagship product - the IQ180/280 - let's see if this has determined the necessary performance. My prediction: The lens is capable of producing great images, but doesn't exploit a 5.2 micron back to its fullest.

If we have to play the MTF game, all P1 need to do is publish some graphs, and I'll shut up.