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07-23-2016, 11:47 PM   #16
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QuoteOriginally posted by noelpolar Quote
f stop used for female portrait should start closed down and open one stop for each 5 years of age!
Fine, but sometimes we need 1.2, 1.1 or 0.95...

07-24-2016, 12:02 AM   #17
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QuoteOriginally posted by J-L SALVIGNOL Quote
Fine, but sometimes we need 1.2, 1.1 or 0.95...
Well, you could accidentally miss-focus the shot
07-24-2016, 01:15 AM   #18
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QuoteOriginally posted by J-L SALVIGNOL Quote
Fine, but sometimes we need 1.2, 1.1 or 0.95...
Well actually the sharper your lens, the larger the f-stop you need. Some explain seriously that the benefit of a lens like basic FA50 f/1.4 is that it is soft at f/1.4-f/2, while it is insanely sharp at f/4 onward. So when you choose the apperture, you not only choose the dof but the sharpness. People always assume perfect sharpness is necessary corners to corners. But that just more work to do in portrait pro or equivalent. Except if you are obssessed with very shallow dof shoot, it is more practical to have a setting that also control sharpness very easily (apperture) than have to get down to f/1.2 to compensate for the lens being too sharp.
07-24-2016, 08:23 AM   #19
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Hey, Nick!
First of all, my congratulations on your new toy! Thanks for sharing your resolution test results, but this test was just among other similar tests posted internet-wide. I wonder if you feel like you're going do something special: what about evaluating the optimal shooting (focus) distance that this lens is designed for? I'm not aware of any such test at all, let alone FA31 model we're talking about here, so if you compare (and share your results here) the per-aperture sharpness at MFD, 1/3 focus throw, 2/3 focus throw and infinity, then you'll be one of a kind!


Looking fwd to seeing your findings,
Zig

07-24-2016, 04:08 PM   #20
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QuoteOriginally posted by Siegfried Quote
Hey, Nick!
First of all, my congratulations on your new toy! Thanks for sharing your resolution test results, but this test was just among other similar tests posted internet-wide. I wonder if you feel like you're going do something special: what about evaluating the optimal shooting (focus) distance that this lens is designed for? I'm not aware of any such test at all, let alone FA31 model we're talking about here, so if you compare (and share your results here) the per-aperture sharpness at MFD, 1/3 focus throw, 2/3 focus throw and infinity, then you'll be one of a kind!


Looking fwd to seeing your findings,
Zig
Your test look a bit complex to set up honestly. f/2.8 and up the lens would be very sharp everywhere... and you need imatest etc to see any actual small differences.

I did a quick test to be sure the lens wasn't a lemon when I received it... That was the goal. And I posted it here to show other how it fared, so one get an idea of a 100% crop. Most often review just provided MTF numbers.

For me the lens work well enough... That's the essential part. And I took a few hundred pictures with it already then... But of real subjects...In the end it is the practical experience of the lens that tell you the truth. Sharpness => Does that mean that f/1.8 and f/2 are really usable or would you always stop down to f/2.2 or f/2.5 at least? Does the lens render better than cheapers lenses like DA35 f/2.4 or DA35 f/2.8 ? What about skin tones?

At some point as I have the 3 (for now) I might do a DA35 f/2.4 vs DA35 ltd vs FA31.. shoot. But the DA35 ltd will go on sale soon.
07-24-2016, 07:41 PM   #21
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I have a zoom lens that is said to be less sharp wide open at its longest focal length, but I find it quite sharp then. When stopped down a stop or two, yes, more things are sharp, but only because there is more depth of field, but the part of the subject that was in focus wide open doesn't get sharper than it was then. Then, too, the lens I am talking about is not especially fast, and especially at its longest length in less than terrific lighting it can be harder to focus and hold still. So, I can see how it could appear in practice to not be as sharp wide open at its longest focal length, but I think it is a mistake based on confusing other issues. Perhaps some similar appearances confuse the issue with the OP's lens.
07-24-2016, 08:55 PM   #22
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QuoteOriginally posted by Siegfried Quote
what about evaluating the optimal shooting (focus) distance that this lens is designed for? I'm not aware of any such test at all!
"Its close-focusing optical performance is not well corrected"
"high lens contrast, particularly at infinity focus."

From ZF/ZE - 25mm f/2.8 Distagon - 25/2.8 Distagon Main Page (diglloyd.com excerpt)
07-25-2016, 11:27 AM   #23
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QuoteOriginally posted by Nicolas06 Quote
At some point as I have the 3 (for now) I might do a DA35 f/2.4 vs DA35 ltd vs FA31.. shoot. But the DA35 ltd will go on sale soon.
Just out of curiosity, why would you sell the 35 Ltd. and keep the 35 f/2.4? Is it performance related or is it based more on lens cost?


Last edited by TheOneAndOnlyJH; 07-25-2016 at 11:32 AM.
07-25-2016, 11:39 AM   #24
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QuoteOriginally posted by TheOneAndOnlyJH Quote
Just out of curiosity, why would you sell the 35 Ltd. and keep the 35 f/2.4? Is it performance related or is it based more on lens cost?
The 35 would sell for 100 max.
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