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05-10-2013, 11:39 AM   #1

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FA* 85mm and A* 85mm f/1.4 mini test

I just had the opportunity to test the A* 85mm 1.4 opposite to my FA* 85mm 1.4 (3rd version) and thought I might share my conclusions here. I compared
them at a medium distance (2-3 meters) with two different subjects only (one for sharpness and one for out-of-focus performance, see samples below).
I cannot judge the performance near infinity, where the A* is said to perform better.

1. Both are really great lenses with a top-level performance.
2. Both have their flaws which can be very obvious under difficult conditions.
3. Both are easily sharp enough even at wide aperture settings.
4. Wide open the A* appears slightly sharper with better microcontrast in the center, while the FA* appears slightly sharper near the edge.
5. These differences are more or less meaningless given the difficulty of getting the plane of focus right. This, and not lens resolution, is really the limiting
factor for sharp images. I shot both lenses over a range of focus settings with tiny adjustments (as small as I could do them) from one shot to the next;
nevertheless I did not succeed in getting the same plane of focus really sharp with both lenses on one subject. Focus bracketing is easier with the A*
because of its longer focus throw and better dampening. AF is not really a solution with the FA* wide open as the tolerance is too wide. (At least, AF is
more accurate than MF with my new K-5 II at wide f-stops; it was not with the K10D.)
6. The FA* has better overall contrast with deeper blacks (note that I compensated for the difference in raw processing because I tried to get the best out
of each lens).
7. The FA* has a wider field of view. The difference is probably more pronounced at closer focus settings because of its IF construction.
8. Both have a great bokeh. From the limited experience of my test shots the FA* is nicer in the background, with more clearly defined "core" details with
a very gradual blur around them (see samples below). The foreground bokeh is not so great with both; it's perhaps a little more nervous with the FA*.
9. The main problem with such lenses is longitudinal chromatic aberration at wide f-stops (to understand this effect, it is very instructive to have a look at
the different colour channels of a wide-open shot). Both have a lot of LoCA; the FA* appears to have more but it can be corrected with the colour fringe
correction tools of Adobe Camera Raw 7.3. The A* additionally has a blue glow around highlights that is not fully correctible.

The pixel-peepers among you may draw their own conclusions from the sample images, shot raw with the K-5 II at f/2.0 (100% crops; as they will be
scaled down by the forum software you should save the images for a comparison). As they were shot through a showcase window, they should not be
used to judge absolute sharpness. Furthermore, the plane of focus is a little in front of the middle lens. I chose this setting because it is the best I
managed to get with the FA*. I post both images in an uncorrected version out of ACR 7.3 and another with ACR's optimum colour fringe correction
settings. Note that with these rather aggressive settings purple and green edges in an image would be affected (that is, discoloured). I was not able to
make the blue glow of the A* image disappear altogether, although it is much less evident than in the uncorrected version.

A* uncorrected

FA* uncorrected

A* defringed

FA* defringed

Last edited by wkraus; 12-23-2013 at 12:18 PM.
05-10-2013, 01:06 PM   #2
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It's interesting to study the optical formulae of these two lenses. The newer FA77/1.8 is almost identical to the older A*85/1.4 so for those of you who want a modern "A*85" with AF, buy FA77 instead.
05-10-2013, 01:12 PM   #3
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Location: Fredericton, New Brunswick
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This would be the first time someone has shown photos of Nikkors, and not been instantly called out for going to the dark side :P

Personally - I like the FA better. Just looks cleaner.

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