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09-22-2011, 07:49 PM - 1 Like   #1
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D FA 50mm f/2.8 Macro vs A 50mm f/2.8 Macro

I told RioRico that since I happened to have both of these lenses at the moment I would put some sort of comparison together. So, reusing some of my initial impressions, here we go:

Without the lens hood on the D-FA the overall size and weight is very close. The hood makes the D-FA twice the length and quite a bit wider than the A at infinity focus, and because the front element is so deeply recessed the A doesn't need a separate hood. Up to 1:2 magnification (where the A tops out) the sizes without hoods remain roughly the same, then the D-FA extends its length another 30% or so to hit 1:1 with the front lens element even with the front of its hood.

The focus ring is much lighter and smoother on my copy of the A (almost too light), however it has obviously been apart at some point in the past. I didn't notice until I set the lenses beside each other but the focusing scale on the A rotates past the infinity marking by about 1 cm in order to actually reach infinity (which I will fix shortly). Manual focus on either lens is perfectly acceptable for macro or portrait distances.

My initial impression is that both lenses are brutally sharp, meter well and produce colours that I'm happy with. The lens formulas are quite different, and the A has 6 aperture blades vs. 8 on the D-FA. The build quality of both lenses is excellent - much better than kit lens level, more solid and with better focus feel than an FA 50mm f/1.4 or other similar FA series lens, but a long ways off from an all metal Takumar prime.

Various photos to show size with and without the D FA's hood (keep in mind that the A 50mm only reaches 1:2 macro on its own at full extension):

And finally some comparison shots under a florescent desk lamp at ISO 800 and ranging from f/2.8 to f/8. I metered at f/2.8 with the D-FA and then shifted the settings in full stops until I hit f/8 with each lens. Hand held because that's how I actually use the lenses most of the time, and the little spider tank (Tachikoma) is about 2 1/4 inches wide by 2 inches tall at the highest point.

A at f/2.8

D FA at f/2.8

A at f/4

D FA at f/4

A at f/5.6

D FA at f/5.6

A at f/8

D FA at f/8

09-22-2011, 08:44 PM   #2
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Thank you for this nice review. This is valuable to this forum,

Great post.
09-22-2011, 10:21 PM   #3
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One more point I forgot to add: the D FA 50mm stops down one step further to f/32 as opposed to f/22 on the A 50mm. Depending on the intended use and with the availability of focus stacking in software that generally won't be a limiting factor.
09-23-2011, 01:01 AM   #4
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Nice comparison! To my flaky eyes, the A looks to be slightly more contrasty, or maybe their T-factors vary slightly due to different generations of coatings. But nice results with each! And it's no surprise that they're well-built. A camera-maker's macro lenses usually are among their signature products. Yes, I'd like to compare their 'feel' with my tank-like MacTak 50/4(1x).

One question: How well do they focus manually at non-macro distances? I ask because on my MacTak the throw from 1m to infinity is only about 1/20 turn. To focus in that range is very tricky, almost impossible for street shooting. That's a metric I'd like to see with manual macro lenses, the 1m-to-infinity throw, which would indicate the applicability for general usage.

09-23-2011, 01:34 AM   #5
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1m to infinity is 45 degrees or 1/8 of a turn on the A and about half that on the D FA. For portrait distances I would generally use autofocus on the D FA since it is fairly fast so long as the lighting is good or the focus is already fairly close. Hunting for focus takes a long time if the camera misses on the first try, which is where quick shift correction or pre-focusing to help the AF comes in. As one would expect AF is pretty much useless in the higher magnification macro range.
09-23-2011, 07:19 AM   #6
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Thanks for your comparison!

I just picked up a FA 50/2.8 and boy is that sucker heavy metal! I'll be trying to log some hours with it. I'm not sure if I'll ever really get into the 1:1 macro stuff and I might be better off with the A version of the lens.

- Sam
09-23-2011, 07:59 PM   #7
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I've played around a little bit more and I think that the D FA is passing slightly more light through than the A at the same settings. In AV mode the D FA selects a shutter speed 1/3 of a stop faster and then gives a slightly darker image. At the same shutter and aperture settings images from the D FA appear a tiny bit over exposed compared to the A.

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