[font color=\'#000000\']Just came across some comments from the Large Format Lens Test Review at
http://www.hevanet.com/cperez/results.html . Here's an extract that seems relevant to your question, but I'm afraid there's a lot of confusion between 'real world' limits and theoretical limits. I have been of the view myself that, say, a 48 megapixel 36x24mm sensor would perhaps rival the quality of 4x5 and allow results that would reflect more closely the true aerial resolution of 35mm lenses. However, I'm beginning to have doubts because of the effects of real world constraints such as camera shake and imperfect focus.
..."Keep in mind, that due to the smaller negative size of the 35mm format,
you need to divide the 35mm on-film resolution numbers by 4 to get the
resolution required of a 4x5 lens for the same on-print resolution for
prints of equal size. In other words, a large format lens capable of
delivering 25 lpmm on film, will be the equal to, in final print
sharpness, the best 35mm lens (using Brian Guyer's 100 lpmm maximum for
an ideal diffraction limited lens). If you review the test results
Chris has posted, all but the very worst of the large format lenses we
have tested are capable of resolving 25 lpmm on film. The ones that
fail, are usually older wide angles at the corners at wide apertures.
Many of them exceed 25 lpmm when stopped down to normal working
apertures. A couple of the really poor performers have obvious defects
(separation in one of the 90mm Angulons for example - keep in mind many
of these older lenses are 40 - 60 years old). Of course, the best of
the modern 4x5 lenses (and several of the older ones, as well) far
exceed 25 lpmm, even in the corners, even at their "worst" aperture.
For example, look at the 110mm Super Symmar XL at f16, it is capable of
resolving, on film, 67 lpmm across the entire 4x5 field. You'd need an
on-film resolution of 268 lpmm from a 35mm negative to get equivalent
sharpness in the final print. Although the best of the current 35mm
lenses may be capable of such a high resolution at some apertures, they
will be not be capable of producing anywhere near such results on film
due to the limitations of currently available films"....[/font]