First, let me say that all the sample images are perfectly fine. They nicely
convey the setting and mood of the gatherings.
On 12/30/2012 11:15 AM, Peter Klein wrote:
> C.H.: I think you may have missed that my pictures were taken at ISO
> 3200. There is a sharpness penalty at that ISO, whether due to noise or
> noise reduction, or reduced microcontrast. And there may be slight
> motion blur at slow shutter speed. I have to experiment with the IS
> off, I've only had it on so far.
>
> Here's a picture of me that a friend took with my camera (at my
> birthday). This is at ISO 800, wide open at f/1.7. Sharp enough?
> <http://gallery.leica-users.org/v/pklein/Thanksgiving12/PB220029+2.jpg.html>
>
> I'm going to try ISO 1600 for my next indoor session. That may be the
> "sweet spot" of IQ vs. noise and noise-related degradation.
There are so many factors interacting on the issues of noise and sharpness here
that I can't see how any clear
conclusions may be reached. I will leave WB aside for others.
1. You are comparing a high grade Leica lens with a consumer grade Zuiko. There
is almost certainly a significant
difference in lens IQ. OTOH, for this size web image, there shouldn't be much
visible difference.
2. The shutter speeds for your sample E-M5 images are at 1/100 to 1/200 sec.
Unfortunately, Oly seems to be unable to
shake a tendency toward body induced shake, and this happens to be right in the
troublesome speed range. He's a good
summary of the issue.
<http://cameraergonomics.blogspot.co.uk/2012/09/micro-43-shutter-shock-revisited-omd-em.html>
So, had you used 1600 ISO, you might have seen better sharpness, probably
attributed it to the lower ISO, whereas most
of the difference would likely be due to another cause. At 800, shutter speeds
would drop out of the troublesome range.
Unlike the aperture stop down induced vibration of the OM bodies, this time Oly
has provided a solution. I have been
using the 1/8 sec. AutoShock setting since reading this, and it has largely
resolved some confusing results I'd been
experiencing. I've noticed no practical difference in use, but others may
notice the tiny lag.
It's quick and easy to switch AutoShock on and off. Once it's turned on in the
Menu, the number of settings in Drive are
doubled, and the AS ones have a diamond by them. Using the Quick Control Panel,
it's four or five clicks for me to
change, from my default highlighted choices, ISO or WB.
The shot of you on your second birthday ;-) is shot at 1/40 and ISO 800,
which eliminate the two primary unsharpness
causes. As above, the 17/2.8 is just fine for this size image. Only pixel
peepers or those making big prints or crops
are likely to see the reported flaws.
3. You are correct that higher ISOs create a sharpness penalty. And it does
seem a bit unfair to compare cameras set at
2 1/3 stops different ISOs. Still, for this kind of shot, intended for the web,
I find 3200 to be the sweet spot. It
allows me to use smaller apertures for greater DOF, the IS (which is certainly
not part of your problems) allows slowish
shutter speeds, and my post processing handles noise, micro-contrast and
sharpness consequences of the ISO setting.
4. Although you say lighting hasn't changed, the actual exposures vary a lot
from year to year. In the first pair, the
exposures are identical. In the second, the Oly shot is exposed 1 1/3 stops
more than the M8, according to the EXIF. 3rd
pair, Oly 1/3 stop more than Leica, 4th. pair, 2 stops! With exposures not
comparable, comparisons of noise aren't, either.
5. As mentioned above, the sweet spot may depend on not only display size, but
on post processing. Even working with the
small image, perhaps flawed by camera vibration, noise and sharpness are fairly
easy to control.
<http://www.moosemystic.net/Gallery/Others/Klein/PC240053-w.htm>
Working with the Raw file, they are quite easy to control. Here, I used 3200 to
get lots of DOF at f8 to get both niece
and her brother in focus as they check out their Christmas presents.
<http://galleries.moosemystic.net/MooseFoto/index.php?gallery=Travel/Seattle/Christmas_2012&image=_C253502rotcroofm.jpg>
Christmas Moose
--
What if the Hokey Pokey *IS* what it's all about?
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