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12-05-2021, 12:30 PM   #31
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QuoteOriginally posted by Gian Quote
here they are, first one is 21, second one 31
In addition to exif can you tell us what you were focussing on ?

12-05-2021, 12:35 PM   #32
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QuoteOriginally posted by Gian Quote
so my technique should be not a variable of the equation.
That is an interesting proposition. Unfortunately such can never be ruled out.


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12-05-2021, 12:36 PM   #33
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I understand that it may be a calibration problem, however, in my days with such a lens you almost would forget focusing a f/8, just set hyperfocal on the barrell and have everything sharp.
I have already returned one, I feel embarrassed to return this one too...
Can't really say it sucks of course, I'm saying that the triplets are better...
12-05-2021, 12:37 PM - 1 Like   #34
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QuoteOriginally posted by Gian Quote
21 - f/8, 1/160 ISO 200
31 - f/8, 1/400 ISO 200
Interesting.

Taking your D FA21 image and dropping the exposure by -0.99 EV - nothing more than that - yields the result below. Obviously the quality suffers from working on your already-heavily-compressed JPEG, but I think it confirms that exposure is one of the issues here...

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12-05-2021, 12:37 PM   #35
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I think I was focusing on the Pinus yunnanensis (the green one) with both.
12-05-2021, 12:38 PM   #36
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QuoteOriginally posted by Gian Quote
I understand that it may be a calibration problem, however, in my days with such a lens you almost would forget focusing a f/8, just set hyperfocal on the barrell and have everything sharp.
I have already returned one, I feel embarrassed to return this one too...
Can't really say it sucks of course, I'm saying that the triplets are better...
It would help if you explained what the problem is
12-05-2021, 12:40 PM   #37
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QuoteOriginally posted by Gian Quote
here they are, first one is 21, second one 31
The first, taken with the 21, is not in focus.


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12-05-2021, 12:40 PM   #38
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QuoteOriginally posted by Gian Quote
21 - f/8, 1/160 ISO 200
31 - f/8, 1/400 ISO 200
Well the exposure is 1.3EV different, and the midtones being too light does tend to look washed out. Mike's edit makes it look much closer - maybe try shooting on M mode to ensure exposure is the same?
12-05-2021, 12:40 PM - 1 Like   #39
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QuoteOriginally posted by Gian Quote
here they are, first one is 21, second one 31
This could be due to a lot of factors (in-camera settings, PP, compression, scaling), but to me the first photo appears over-sharpened. With newer lenses that are sharper out of the box, additional sharpening can backfire. Could be part of the reason why you're not happy with the result.

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12-05-2021, 12:44 PM   #40
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QuoteOriginally posted by Gian Quote
however, in my days with such a lens you almost would forget focusing a f/8, just set hyperfocal on the barrell and have everything sharp.
Have a look at the Pentax site I linked to earlier D FA Limited | PENTAX Limited Lens Special Site | RICOH IMAGING

I think apart from focus or exposure issues, you may have bought the wrong lens.
12-05-2021, 12:52 PM - 1 Like   #41
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It's not so straight-forward to compare two lenses of different focal length. In order to compare sharpness properly, the subject detail should occupy the same relative size in the frame for each test shot, same exposure parameters (use manual mode) and a tripod with timer or a remote trigger, all lenses should be focused at the same place. Then use the same raw conversion parameters for JPEG comparison. That said, it's possible that the 21mm doesn't resolve as much as the 31mm in corners, I've never seen an ultra wide prime lens as good as a 35mm, 50mm or 85mm prime lenses, ultrawide lenses are just much harder to design optically. If the DFA 21 should be compared, it should be compared with other lenses having similar focal lenght, the DFA 15-30 and other ultrawide primes.
12-05-2021, 01:04 PM   #42
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@Gian - Going back to my comment re the lighting, the time of day was quite different between the two shots, I think? Or even the time of year, looking at the colour of foliage and the snow on the mountains? The light is at a lower angle in the FA31 shot, so the contrast and shadows in the mountains (for example) are more accentuated and it's an overall more-flattering light.

If you're comparing output from two lenses based on an outdoor scene, you really need to shoot both side by side, or at least in sequence within a short space of time so that lighting and other conditions remain consistent. Good times of day for those comparison tests - or even just for testing a single lens - are, IMHO, around the "blue hour" and "golden hour" when the angle of the sun is much lower, and details are more defined. I prefer the golden hour - or at least late on in the afternoon - but either works well...

Last edited by BigMackCam; 12-05-2021 at 01:19 PM.
12-05-2021, 01:05 PM   #43
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Every image I have seen from this lens so far on other posts is excellent.

QuoteOriginally posted by Gian Quote
I think I was focusing on the Pinus yunnanensis
My emphasis on your quote.

I suggest if you want folk to examine your pictures for potential issues with your copy of a lens, that you provide accurate information. Sorry if that sounds harsh but it is the best empirical approach to problem solving.
12-05-2021, 01:20 PM   #44
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QuoteOriginally posted by Adam Quote
This could be due to a lot of factors (in-camera settings, PP, compression, scaling), but to me the first photo appears over-sharpened. With newer lenses that are sharper out of the box, additional sharpening can backfire. Could be part of the reason why you're not happy with the result.
these are OOC Jpegs, so there is no post processing

---------- Post added 12-05-21 at 21:22 ----------

QuoteOriginally posted by stevebrot Quote
The first, taken with the 21, is not in focus.


Steve
I would say nothing is in focus, which explains my complaint of lack of detail

---------- Post added 12-05-21 at 21:26 ----------

QuoteOriginally posted by biz-engineer Quote
It's not so straight-forward to compare two lenses of different focal length. In order to compare sharpness properly, the subject detail should occupy the same relative size in the frame for each test shot, same exposure parameters (use manual mode) and a tripod with timer or a remote trigger, all lenses should be focused at the same place. Then use the same raw conversion parameters for JPEG comparison. That said, it's possible that the 21mm doesn't resolve as much as the 31mm in corners, I've never seen an ultra wide prime lens as good as a 35mm, 50mm or 85mm prime lenses, ultrawide lenses are just much harder to design optically. If the DFA 21 should be compared, it should be compared with other lenses having similar focal lenght, the DFA 15-30 and other ultrawide primes.
I totally agree, and I am not trying to do a scientific comparison, it's just that after a few hundred of shots you know what sort of result you can expect, and the 21 is consistently less detailed than 31/43/77.
12-05-2021, 01:27 PM   #45
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QuoteOriginally posted by Gian Quote
these are OOC Jpegs, so there is no post processing
If these are straight-from-camera JPEGs with no change in camera settings, there's something not right... There's a huge section of "mush" in the brown foliage, and - as Adam says - what appears to be sharpening artefacts. We're not seeing that kind of problem in any of the other shots from this lens...

Honestly, I think you have some work to do before concluding the D FA21 isn't as good as the other Limiteds, and potentially returning your second copy. I'm happy to help with defining your test plan, if you've the appetite to set up and conduct the tests in a controlled manner. Feel free to PM me if you like, or I'm happy to discuss openly in this or another thread...
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