I'm still just waiting to know (no images required) if you can clearly
discern the difference in focus (wide open and with liveview) between
two high contrast targets one at 5 meters the other at 5.5 meters or 5
meters and 6 meters. A significant point of my argument says that you
can't. If you can, I lose.
But something to be cognizant of:
The cameras that I checked (E-3, E-30, E-620) all have the same size LCD
(230,000 pixels, whatever that means) but the E-3 has 10.1 MP and 2736
pixels vertically while the other two have 12.3 MP and 3024 pixels
vertically. But despite these specifications they all claim to do 10X
in liveview and 14X in playback. I can't believe they are doing more
than 1:1 magnification in playback so I believe that 1:1 requires at
least 14X. That equally means I don't believe that 10X mag in liveview
is 1:1. That's more information to me that liveview focusing doesn't
give you the pixel resolution you see in your full pixel crop images and
means to me you can't focus that closely.
But, as I said above, I'll concede if you say you can differentiate
those two high contrast targets at those distances at 24mm and wide open.
Chuck Norcutt
Ken Norton wrote:
>> 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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