It may be just me, but I'd compare the f/1.7 lens with the f/1.4 *AT* f/1.7.
Reason? If they're both about the same at f/1.7, then the f/1.4 lens is just
as good as the f/1.7 for all purposes you would have used the f/1.7. Bonus:
a little more aperture available to control DOF with the 1.4.
Bob...
---------------------------------------------------------------------
I don't mind if you don't like my manners.
I don't like them myself. They're pretty bad.
I grieve over them on long winter evenings.
-- Humphrey Bogart, "The Big Sleep"
From: Luiz Felipe
Sent: Friday, February 11, 2011 9:32 AM
Larry, you and Paul got me thinking about a test with Yvon's AF target -
just to make sure there is no micro shift made evident by the 1.4 aperture.
I understand the 1.4 lenses got slightly worse results wide open than the
1.7, and my rather crude tests point in the same direction. If you get to
test it, post the results, ok?
Of course I'd still go for the slightly OOF pic, as opposed to the words
describing the UFO.
Luiz Felipe
luiz.felipe at techmit.com.br
http://www.techmit.com.br/luizfelipe
Larry's ideas:
>On Feb 10, 2011, at 4:43 AM, Paul Stenquist wrote:
>>
>> Did you manual focus? If you're shooting wide open, and your autofocus is
off by even a relatively small amount, your results will be soft. The
performance of this lens on my K20 is what first convinced me that fine
focus adjustment is a necessity. I've since seen that the FA50/1.4 required
more adjustment than any of my DA or DA* lenses.
>> Paul
>
>I ran versions of the test with both autofocus, and manual focus with the
katzeye, and got very similar results.
>
>Some of it was CA. Oddly, to me, this lens doesn't seem to be in the
lightroom lens correction database.
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