> I finally realized what I was driving at in the comments about viewing
> the image at 1/4, 1/3 and 1/2 life size and that has to do with
> resolution of the LCD on the camera during live view at 10X. If the
> camera isn't actually taking you to full pixel view but rather to just
> 1/2 of that then the difference *while focusing* between the left and
> right images in AG's 3rd page is not visible on the focusing screen.
I think that at 10x on the L1 it is full pixel view.
> ...in order to simulate what it will look like on a print. At 1/3 life
> size the difference between left and right disappears and is even hard
> to discern at 1/2 life size.
Well, I think that was one side point I was driving at which I didn't
flat come out and say. In those samples we're looking at pixel-view.
In a reasonably-sized print, what is out-of-focus may still be
in-focus to the human eye. (Eagle-Eyed Moose being an exception, of
course).
I haven't prepped anything for web display because I had to prepare
for a photo assignment tonight, although I did at least convert the
files to tiffs and looked at them side-by-side in PWP, but the images
from yesterday's tests were different but still showed a difference. I
photographed these life-sized sculptures using the same equipment
setup as before. I can guarantee with absolute certainty the focus is
perfectly matched. Not only that, but I can guarantee that for a close
in working distance (around one body-length, give or take), that the
OM-Z 24mm is as sharp as the Leica.
You'll just have to bear with my verbal description here until I have
a chance to do something with the set of photos, because I've got a
bunch of them and don't know how to present them yet.
The bronze sculptures were in shade, but parts of the background were
in full sun. Therefore, I got excellent contrast as well as CA
promoting conditions. If there is anything ugly in the lenses, it will
show up in this situation. At F2.8, the 24mm lens had pronounced
purple fringing, but F4 was remarkably clean. From F4 to F8 the
sharpness and contrast as pretty close to identical--just with
increasing DoF. At F11, diffraction starts to reduce contrast, but the
sharpness is still there and recoverable. At F16, diffusion has caused
a marked decrease in contrast and probably ultimate resolution--but
really only a visible issue at 1:1. I was feeling kinda bad about the
24mm lens after the first test, but for my usual paid photography,
which involves people, not landscapes, I'd suggest the 24mm lens
without hesitation. One thing to remember is that this is viewing the
pixels 1:1 from a crop sensor camera. When used on a full-frame camera
with lower enlargement ratio and/or film resolution limits, I'd say
that the lens is fully capable of resolving to the limits of most
films at the majority of apertures. I know that in real life this has
been pretty true. But with a caveat. The 24mm F2.8 lens doesn't seem
to do landscapes quite as well as closer in photography. It definitely
appears to be optimized for the 1-3m range, not infinity. For
landscape photography, I always try to stay around F5.6-F8.
Oh, what about the DoF in my second test? In my test conditions it is
a little harder to see the lens flaws which showed up in that highly
detailed field of weeds and flowers test. But the differences in bokeh
growth is apparant. To Chuck's point, though, the differences when
viewed at a lower magnification than 1:1 are greatly reduced. In fact,
with a bit of curves adjustment you would be hard pressed to pick one
over the other except for an uncanny 3D edginess in the Leica images
which is not unlike a slight dose of LCE has been added to the shot.
One topic which I've been avoiding in this entire discussion is
"preference". I've been praising the Leica lens for various reasons,
but will say that this apparant increase in DoF does have drawbacks.
The backgrounds tend to be a little more busy. The bokeh is not
allowed to bloom and grow like some lenses do and from a purely
artistic perspective I would select the OM-Z 24mm F2.8 lens over the
Leica as the flaws actually enhance the image and provide a layering
(subject layer, background layer) approach to the picture. The Leica
doesn't give that same two-object plane approach, but gives the entire
image--both foreground and background a unified approach with good
subject isolation, but the background is still either detailed or
appears to contain detail.
The reality is, both lenses are excellent. Different, but excellent.
AG
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