On 11/19/2011 5:22 AM, Chuck Norcutt wrote:
> Such tests are really hard to do. The Tessar looks a bit mis-focused at
> f/8 (see the blue band on the vase)
Ah, but I wasn't focusing on the vase. This was all done on a tripod, using
live view enlarged to focus on the same part
of the flower as carefully as I could. Thus any difference in focus out of the
focal plane 'should' be a reflection of
DOF. Whether the tessar design gives slightly different DOF/front/back
characteristics and/or the slightly longer actual
focal length had an effect, I don't know.
> and the Tamron is obviously at a different focal length as seen in the
> perspective.
Yeah that big a difference surprised me, I set it at an indicated 50 and the
EXIF said 50 mm, bu it clearly shorter. If
I do this again after the canon finds it's way home, I'll adjust the zoom and
maybe even use a focusing rail on the
others to get closer subject size matching.
> In a digital world there's probably not a whole lot of performance difference
> to worry about here...
I do think the color differences are significant, unless one does ICC profiles
for each lens and/or shoots reference
cards a lot.
> at least at this image size. That said, the Tamron did very well for such a
> long range zoom.
There seems to be a general feeling that long range zooms are bound to be poor
lenses. I haven't found that to be the
case with the ones I have. As good as first rate primes, generally not. Better
than shorter range kit zooms, yup. And as
I've said and demonstrated before, this one is an excellent CU lens at 300mm.
In field use, I think it s actually more
likely to get a great close-up than a dedicated longish macro lens.
Moose
--
What if the Hokey Pokey *IS* what it's all about?
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|