With the newer mirrorless cameras, (and even 35mm or MF) where the lens
is so close to the sensor, it seems a near impossibility to get such LF results,
simply because of extra retrofocus elements required. More than just the
lp/mm sharpness, the effect is most likely due to the distance from lens to
film plane, allowing for a more symmetrical lens. Of course that distance
means larger film, but I believe it is the distance of lens to film plane that
allows for a simpler lens design that achieves good resolution, but with
the result in smoother transition to OOF areas.
Achieving that effect with modern cameras and complex lenses might be doable
by capturing multiple focus points and combining the result in such a way that
some of the desired OOF points are blurred in a controlled way. Maybe with
a Lytro Multi-Focus Camera, the image data could be processed to create that
effect.
Another way might be to create a spherical sensor, sort of like an eyeball.
Maybe add light fibers to a flat sensor to create the spherical focus point.
Maybe it is because we see with eyeballs, that the effect in the LF photo,
with smoother transition to OOF areas matches better how we perceive
the world, hence is more pleasing to view.
Wayne S
At 11/7/2011 09:39 AM, you wrote:
>Actually, most modern LF lenses have specs comprable to (or sometimes better
>than) small-format lenses, and almost always without the inherent
>distortion in retrofocus wide-angles, since LF lenses are often close to
>symmetrical.
>
>The aforementioned Chris Perez lens tests show some fine specs for modern LF
>glass, with up to 85+ lp/mm test results. That's a superb resolution, even
>by the standards of the best 35mm lenses. Look at the Mamiya 7 tests he ran
>if you really want to be wowed.
>
>Most 35mm glass doesn't hit 50 lp/mm, at least not in the corners, btw. Old
>tests from Modern Photo and pop photo magazines bear this out.
>
>Most LF glass peaks at between f/11 - f/22, with f/16 often being the 'best'
>aperture. Depending on subject, you can shoot @ f/16 and still get great
>DOF, since movements are an option on LF cameras.
>
>As mentioned, with the huge film real estate, there is a signficant
>advantage to MF and LF film, even if the lenses weren't up to par vs. 35mm
>(though they often are.)
>
>-Ed
>
>
>On 11/5/11 6:16 AM, "olympus-request@xxxxxxxxxxxxxxxxx"
><olympus-request@xxxxxxxxxxxxxxxxx> wrote:
>
>> Subject: Re: [OM] Lens design, bokeh, etc.
>> To: Olympus Camera Discussion <olympus@xxxxxxxxxxxxxxxxx>
>> Message-ID: <CAD9E957.70BF%chris@xxxxxxxxxxxxxxxxxxxxxx>
>> Content-Type: text/plain; charset="US-ASCII"
>>
>> I think that is a quality of large format itself, not the lens designs.
>> Large format lenses are actually not very sharp, because they're typically
>> stopped down quite a bit. That portrait of Churchill may well have been
>> shot with the lens at f22 or 32, maybe even 45. It was done on 8x10 film,
>> if I remember right, which would have meant a 300mm lens (if he used a
>> 'standard' lens). A 300mm lens or anything around that focal length, has
>> very little depth of field, even at f32, when close enough to the subject
>> to do a portrait like that. You have to stop down that much just to keep
>> the whole face in focus! Problem is, at f45 diffraction limits a lens to
>> about 10 lines per mm resolution! At f32 you get more, but I can't
>> remember the number. Its not high compared to our 35mm format lenses that
>> give 50 l/mm at most apertures they come with! The extremely large film
>> captures enough detail, even with such low lens resolution to beat the
>> hell out of 35mm or medium format and their sharper lenses. That is why
>> you get that smooth but detailed look!
>>
--
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