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08-08-2018, 01:01 AM - 4 Likes   #1
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D FA* 50mm F1,4 - aperture invariant ;-)

Don't worry, the title is obviously an exaggeration.

Nevertheless look at the following 100% crops of a church tower shot with 36 MPx:

at F1.4:



at F5.6:


at F16:


Yes, you can spot differences on a monitor in a direct comparison of these 100% crops. But who earnestly believes any non-photo-forum-freak would ever see any difference/effect when watching the full image alone even as a large print?

I am just astounded about what modern lenses can deliver.

08-08-2018, 02:13 AM   #2
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Impressive wide open, but the F16 is soft somehow. The F5.6 is so sharp.

Seb
08-08-2018, 03:32 AM   #3
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Wow thats pretty impressive.
The f16 looks pretty much as I would expect (due to onset of diffraction) but its a good sign that its significantly sharper at f1.4 than f16.
The contrast at f1.4 looks great too.
08-08-2018, 04:16 AM   #4
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i like mine as well :-)

08-08-2018, 05:12 AM   #5
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From which area of the image the crops were taken - the center?
08-08-2018, 05:20 AM   #6
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Probably the exaggeration you were looking for is “diffraction limited”, but “aperture invariant” sounds much cooler.
08-08-2018, 06:34 AM   #7
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Whilst we can obviously see the difference between f/1.4 and f/5.6 (as well we might), this lens can clearly be used wide open all day long. It's not a case of shooting at f/2 to get decent results and using f/1.4 in a pinch, like most fast-aperture lenses...
08-08-2018, 06:46 AM - 1 Like   #8
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QuoteOriginally posted by bassek Quote
Impressive wide open, but the F16 is soft somehow. The F5.6 is so sharp
At f/1.4, shutter speed is 1/6400

At f/5.6 shutter speed is 1/400

At f/16, shutter speed is 1/50, diffraction + shutter shock (<1/200) to be expected. f/16 should be shot at ISO500 in order to only get the blur of the lens.

08-08-2018, 07:05 AM   #9
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As alredy the battery grip is reported to reduce the shutter shock, a next to 1kg lens in front wil do even more so.
08-08-2018, 07:23 AM   #10
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F16 does soften a little as expected, but it's less than you might think (I've tested mine) and the contrast stays quite nice. I have no problem shooting it at F16. Aperture invariant is only a slight exaggeration. : )
08-08-2018, 08:31 AM   #11
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Aperture invariant maybe, but clearly too heavy. By f16 the camera is drooping quite a bit already.
08-08-2018, 12:26 PM - 2 Likes   #12
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QuoteOriginally posted by johnkrumm Quote
F16 does soften a little as expected, but it's less than you might think (I've tested mine) and the contrast stays quite nice. I have no problem shooting it at F16. Aperture invariant is only a slight exaggeration. : )
QuoteOriginally posted by BigMackCam Quote
Whilst we can obviously see the difference between f/1.4 and f/5.6 (as well we might), this lens can clearly be used wide open all day long. It's not a case of shooting at f/2 to get decent results and using f/1.4 in a pinch, like most fast-aperture lenses...
Exactly my thoughts. Results look great regardless of chosen aperture and so there is no need to waste thoughts on "image quality" when choosing aperture.
That lens will probably stick to F1.4 quite a long time (for the rest I can use the DFA 24-70 as well).
08-08-2018, 02:21 PM - 2 Likes   #13
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QuoteOriginally posted by beholder3 Quote
Exactly my thoughts. Results look great regardless of chosen aperture and so there is no need to waste thoughts on "image quality" when choosing aperture.
That lens will probably stick to F1.4 quite a long time (for the rest I can use the DFA 24-70 as well).
As good as the 50 is wide open (and I've never seen better in a fast 50), even stopping down to f/1.8 gives a startling improvement. What I'm finding is that I can shoot wide open, or close to it, with confidence that I'm not going to get a smeary mess, something I have not been able to do since my Nikon F2 days and my old Nikkor 50/1.4, which was pretty sharp wide open, but had brutal enough bokeh that I never wanted to see anything out of focus.
08-08-2018, 03:34 PM   #14
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QuoteOriginally posted by Wheatfield Quote
As good as the 50 is wide open (and I've never seen better in a fast 50), even stopping down to f/1.8 gives a startling improvement. What I'm finding is that I can shoot wide open, or close to it, with confidence that I'm not going to get a smeary mess, something I have not been able to do since my Nikon F2 days and my old Nikkor 50/1.4, which was pretty sharp wide open, but had brutal enough bokeh that I never wanted to see anything out of focus.
How is the bokeh wide open with specular lights? This is one aspect where the old FA 50/1.4 is truly horrible, impossible to use for urban night photography not even at f/2.8. Not sure I would take the weight penalty just for that though...
08-08-2018, 03:48 PM   #15
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QuoteOriginally posted by mirocal Quote
How is the bokeh wide open with specular lights? This is one aspect where the old FA 50/1.4 is truly horrible, impossible to use for urban night photography not even at f/2.8. Not sure I would take the weight penalty just for that though...
I'm sure Bill will respond, but from other test shots that I've seen, the D FA50/1.4's out-of-focus rendering at f/1.4 is superb. I own the old FA50/1.4, so I know exactly what you mean... wide open rendering is not its strong suit
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