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10-17-2021, 07:42 AM   #31
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QuoteOriginally posted by normhead Quote
For the flower image used to assess the lens, I've had similar results with my FA 50 macro and D FA 100 macro, and neither of them is "soft".
I've had similar image with my M50 f1.7 wide open up to about f2.8 or f/4, but it's equally soft at infinity. The special site only show this one picture of the yellow flower closely focused wide open, they don't show how it's like if the subject is further away.

10-17-2021, 07:58 AM - 1 Like   #32
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QuoteQuote:
One of the adjustments we made in response to the test shooting results was to control the level of spherical aberration. In dose-range photography using open and larger apertures, spherical aberration was intentionally increased by a considerable level to produce a soft-focused image in which the in-focus plane in the image field appeared to be rather vague and indiscernible. ff the adjustment became too excessive, however, the image would appear completely blurred. To avoid this problem, we adjusted the level of spherical aberration bit by bit in test shootings until we discovered the optimum level, one that assured the imaging characteristics dose to our imaging goals. The final decision was made by the Limited Committee following its sensibility evaluations.

However, the lens wasn't designed to produce soft-focused images at all aperture settings. Anticipating that photographers might also prefer to close the aperture down in scenic photography, we designed the lens to produce rather crisp-focused images when the aperture is closed down to F4 or smaller.
The second paragraph suggests the lens is soft wide open...
The first paragraph explains the trade off. smooth bokeh or razor sharp images and that a compromise was made between absolute sharpness and a smooth background. What is not clear is how much softness was created to produce superior bokeh, clearly a bit of softness was introduced, but whether or not that would be soft by any other standard is open to speculation.

For those of us interested in overall rendering absolute sharpness is not a defining characteristic. For close up photography, clean smooth bokeh is worth a lot more than absolute sharpness. In fact, I can think of very few images where absolute sharpness is even pleasing. Which is reinforced by how little I like the rendering of those super sharp Zeiss lenses with their high resolution but less than optimum rendering.

I've always liked the rendering of the 31 and how it compares to any lens I've seen it compared to, and it's in a similar class. Great bokeh wide open, for flowers and close ups, (because in extreme close-ups at wide apertures is where you are most likely to encounter wonky bokeh...) and then sharp edge to edge ƒ/4 and beyond for landscapes. To me it's the ultimate design for nature. It's like two lenses in one. Too bad they're so expensive.

But since I have 14mm and 24mm covered, I may have to make an effort to acquire one. It would kind of complete the set.

Last edited by normhead; 10-17-2021 at 08:50 AM.
10-17-2021, 09:38 AM - 1 Like   #33
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QuoteOriginally posted by robbiec Quote
It is in the development story or part of the DFA Limited Special site. Phrasing is not exact but I intimated that close up = more bokeh friendly, further out acting more like a normal lens. I'll find the exact phrasing and revert.
It is not a one trick pony and it'll be fun finding out exactly what it can do

From the 'A message from the development team' - "To achieve this goal, we designed the lens differently from conventional models: we intentionally retained a certain level of aberration to create a mild bokeh effect in close-range photography, while creating sharp, crisp images of distant scenery at closed-down apertures. While we were well aware of a mellow image rendition of close-range scenes —a feature common to the Limited Lens-series snapshot lenses — we pursued the sharpness in long-distance scenic photography using a 21mm wide-angle perspective."

My take from this is that they designed to have good bokeh handling close up but further out i.e. towards infinity start ramping up the resolution.
10-17-2021, 10:04 AM   #34
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The product page is a bit more firm in suggesting good performance across the field.
QuoteOriginally posted by ricoh dfa21 product page:
Exceptional optical design to minimize image fuzziness — a problem typical with ultra-wide-angle lenses — even at the edges
By incorporating a large-aperture negative meniscus optical element and a biconvex aspherical glass-mold optical element, this lens assures outstanding image performance for sharp, crisp images without any trace of fuzziness even at the edges. In addition, four ED (Extra-low Dispersion) and one Super ED (Extra-low Dispersion) glass optical elements help reduce chromatic aberration to a minimum.
The probably decided to focus very narrowly on the "leading feature" in the message from the development team to keep the message simple.

10-17-2021, 10:53 AM   #35
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QuoteOriginally posted by house Quote
The product page is a bit more firm in suggesting good performance across the field.


The probably decided to focus very narrowly on the "leading feature" in the message from the development team to keep the message simple.
Who here would understand anything else?
10-17-2021, 10:53 AM   #36
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QuoteOriginally posted by acoufap Quote
It has 67mm filter thread.
That's good news.
10-17-2021, 05:49 PM   #37
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Only tests will tell, both by labs and by people submitting their own images. Everything else is hyperbole, including advertising as are these statements, or speculation. Not saying this release is not a good thing. The statements seem to indicate excellent central sharpness wide open with very fine bokeh, with excellent edge-to-edge sharpness stopped down slightly. This seems very promising. The size is larger then the FA 31mm Ltd, but not by all that much, not bad for such a wide angle with its aperture, yet the FA 31mm is about one stop faster. Still pretty good for such a lens.

For me, it remains to be seen if this lens is something I can use on a regular basis. I am very happy with the performance of my old Tokina 20-35mm f/3.5-4.5 (actually tested as 19mm). It takes a 77mm filter, same as several of my other lenses, and it is not all that large or heavy. But the moderate size and f/2.4 aperture of this new ultra-wide Ltd lens, as well as its fine build with DC AF and WR certainly do make for desirability!


Last edited by mikesbike; 10-17-2021 at 06:19 PM.
10-17-2021, 05:57 PM   #38
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QuoteOriginally posted by mikesbike Quote
Still doesn't quite seem in line as a 4th Amigo, however, as the other 3 all offer far larger apertures- 2 stops plus.
I'm confused by this statement here... the new 21 is f/2.4 and the 31 and 77 are both f/1.8 - that's a difference of under a stop...
10-18-2021, 12:35 AM   #39
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QuoteOriginally posted by bertwert Quote
I'm confused by this statement here... the new 21 is f/2.4 and the 31 and 77 are both f/1.8 - that's a difference of under a stop...
An ultrawide lens would become much bigger if it has an 1.8 aperture, due tue larger front lens.
f2.4 is an compromise to size (and weight).
10-18-2021, 02:23 AM - 1 Like   #40
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QuoteOriginally posted by mikesbike Quote
Only tests will tell, both by labs and by people submitting their own images. Everything else is hyperbole, including advertising as are these statements, or speculation. Not saying this release is not a good thing. The statements seem to indicate excellent central sharpness wide open with very fine bokeh, with excellent edge-to-edge sharpness stopped down slightly. This seems very promising. The size is larger then the FA 31mm Ltd, but not by all that much, not bad for such a wide angle with its aperture, yet the FA 31mm is about one stop faster. Still pretty good for such a lens.

For me, it remains to be seen if this lens is something I can use on a regular basis. I am very happy with the performance of my old Tokina 20-35mm f/3.5-4.5 (actually tested as 19mm). It takes a 77mm filter, same as several of my other lenses, and it is not all that large or heavy. But the moderate size and f/2.4 aperture of this new ultra-wide Ltd lens, as well as its fine build with DC AF and WR certainly do make for desirability!
Limited in this case refers to the size of the lens. To have a 21 mm lens and a 67mm filter thread, you aren't going to have the lens be f2 or wider. It just would be too big -- or would suffer from significant aberrations/vignetting/distortion. I think this lens fits in perfectly with the Limited ethos.
10-18-2021, 05:22 AM - 1 Like   #41
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QuoteQuote:
Of course, with such a wide angle the smaller max aperture allows for a smaller lens size, but it seems at least f/2.8 could have been possible, still with very good performance wide open.
2.4 is wider than 2.8.
10-18-2021, 05:10 PM   #42
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QuoteOriginally posted by house Quote
Anything but full blown positive thinking isn't very well received here but the same happened when I suggested Pentax K-3 III face detection implementation would likely only be in full auto as in previous models. Some users here were outraged by the suggestion Ricoh would do something like that. Awfully quiet now when it turned out to be just as predicted.
Well, what's not well received in a credible forum is misinformation, House!

The face detection implementation is either full auto as in Live View of previous models, or a particular zone in the OVF.

This Limited looks great. Who needs two kidneys, anyway?
10-18-2021, 08:26 PM   #43
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QuoteOriginally posted by clackers Quote
The face detection implementation is either full auto as in Live View of previous models, or a particular zone in the OVF.
Where's the zone?
10-19-2021, 03:18 AM   #44
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QuoteOriginally posted by leekil Quote
Where's the zone?
So, according to the manual, the K-3 III has 101 focus points.

A zone is 21 of them.
10-19-2021, 04:30 AM   #45
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QuoteOriginally posted by clackers Quote
So, according to the manual, the K-3 III has 101 focus points.

A zone is 21 of them.
I guess
QuoteOriginally posted by repaap:
Repaap
could clarify but I though he explained that eye detect works in scene detect mode only. No way of initiating eye detect with a small area or spot.
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