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12-08-2021, 02:49 AM   #136
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QuoteOriginally posted by Serkevan Quote
I'm sure we could study the physical parameters, but "pixie dust" sounds wonderfully artsy, doesn't it?
I've never subscribed to the notion of "pixie dust", or never thought I did... but maybe I do, and simply call it "character". But as we see all the time in these forums, everyone's idea of pixie dust seems to be slightly (or even wildly) different

12-08-2021, 03:46 AM - 1 Like   #137
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QuoteOriginally posted by BigMackCam Quote
I've never subscribed to the notion of "pixie dust", or never thought I did... but maybe I do, and simply call it "character". But as we see all the time in these forums, everyone's idea of pixie dust seems to be slightly (or even wildly) different
I have always thought that "pixie dust" is a mixture of a lens's ability to have smooth transitions from in focus to out of focus areas, good contrast and micro contrast, and out focus rendering that is not overly busy. I don't think sharpness actually has much to do with this, even though many people focus on sharpness a lot.

My experience with the FA 77 and FA 31 suggests they do very well with these sorts of factors, even if edge sharpness isn't always perfect.

Last edited by Rondec; 12-08-2021 at 10:05 AM.
12-08-2021, 03:56 AM   #138
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QuoteOriginally posted by Rondec Quote
I have always thought that "pixie dust" is a mixture of a lenses ability to have smooth transitions from in focus to out of focus areas, good contrast and micro contrast, and out focus rendering that is not overly busy. I don't think sharpness actually has much to do with this, even though many people focus on sharpness a lot.
I suspect you're right... in which case, the "character" I refer to may be wider in scope than "pixie dust" and not necessarily consistent between different lenses...
12-08-2021, 05:11 AM - 1 Like   #139
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QuoteOriginally posted by Rondec Quote
I have always thought that "pixie dust" is a mixture of a lenses ability to have smooth transitions from in focus to out of focus areas, good contrast and micro contrast, and out focus rendering that is not overly busy. I don't think sharpness actually has much to do with this, even though many people focus on sharpness a lot.

My experience with the FA 77 and FA 31 suggests they do very well with these sorts of factors, even if edge sharpness isn't always perfect.
I'm not particularly sure it doesn't play a role - the central (and mid-frame) sharpness of the 43 and 77 is very high at f/5.6-8 and at that aperture, the OOF background is still buttery smooth, which leads to a very noticeable 3D pop effect.


This is a strong crop at f/7.1 (it's a downscaled JPG weighing 6 MB so there are some artifacts*), from a friend - I'd rather not post the entire photo, sorry about that :


The background is somewhere like 2-3 m away from the subject, I reckon. I was about 5 meters away or so. My friend's whole body takes ~2/3rds of the sensor length (I shot vertical). I did use fill flash (HSS, shutter speed was 1/800 at ISO 100) which also enhances the "pop" effect, though with HSS it's less noticeable in my very limited, I-suck-at-portraits experience.


*Not around the legs though - that's just hair .

12-08-2021, 09:43 AM - 2 Likes   #140
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QuoteOriginally posted by phat_bog Quote
Well BigMackCam all the pics taken in AF mode with all 3 cameras and all AF micro adjustements possible were all slightly or totally out of focus at 2.4 so i don't see the point of posting them. In MF mode, at 2.4 sometimes got more sharpness in the corners than in the center.
That is typical of a lens that needs its AF adjusted to the body (or bodies). I'm not sure if your copy of the lens was beyond the available adjustment parameters, or if you just decided it's not worth your time and returned the lens - but the root cause here is that you never got the AF adjusted for the lens/body.

I have an HD DA 21mm (different lens of course) and wasn't very happy with it and then did some careful focus fine tuning with my K-3 and voilą - images are wonderfully sharp.

The problem with these wide angle lenses is that even when the focus adjustment is clearly off, that still won't show unless you pixel peep. Looking at the image as a whole makes you think it's in focus, just not as sharp as you'd like.
12-08-2021, 10:21 AM   #141
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QuoteOriginally posted by Kunzite Quote
Am I the only one having difficulties in identifying a lens' "character"?
Sometimes I see something special in a picture; how much is the lens, how much is the scene, and why can't I reproduce the 3D pop I've seen in that one DA 21mm F:3.2 picture that made buy the lens?

Softness is obvious. CA is obvious. Distortion is obvious. But if my D FA* 50mm f/1.4 lacks "character", I'm not sure I can see it
I had the same issue (a bit of softness) with my HD DA 21 f3.2 and fine focus adjustment took care of that. 3D pop is now available as well (you can't have 3D pop when the subject is not in focus...)

But yes CA is an issue at the corners with this lens, no question about it. It's a compromise from the pancake design, which is what makes me take this lens out much more often than my DA*16-50.

In regards to the DFA 21mm f/2.4 Limited, it could be possible that in terms of sheer sharpness throughout the whole frame, that the DFA 15-30mm f/2.8 might be slightly superior (I don't know this for a fact, of course) but in terms of center sharpness, microcontrast and the "3D effect" the DFA 21 Limited should be superior... the FA Limited designs were always about leaving a bit of uncorrection and field curvature, to help with bokeh and rendering... people just need to decide what is more important to them.
12-08-2021, 10:40 AM   #142
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QuoteOriginally posted by ChristianRock Quote
I had the same issue (a bit of softness) with my HD DA 21 f3.2 and fine focus adjustment took care of that. 3D pop is now available as well (you can't have 3D pop when the subject is not in focus...)

But yes CA is an issue at the corners with this lens, no question about it. It's a compromise from the pancake design, which is what makes me take this lens out much more often than my DA*16-50.

In regards to the DFA 21mm f/2.4 Limited, it could be possible that in terms of sheer sharpness throughout the whole frame, that the DFA 15-30mm f/2.8 might be slightly superior (I don't know this for a fact, of course) but in terms of center sharpness, microcontrast and the "3D effect" the DFA 21 Limited should be superior... the FA Limited designs were always about leaving a bit of uncorrection and field curvature, to help with bokeh and rendering... people just need to decide what is more important to them.
I doubt the 15-30 is better but no one has done comparisons yet. It would be interesting to see as the 1530 is well regarded in other mounts as well.

12-08-2021, 10:50 AM   #143
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One thing is for sure - the beautiful 3D rendering I'm seeing with the DFA 21mm Limited, I don't see with the DFA 15-30mm zoom. Reminds me of Zeiss.
12-08-2021, 11:01 AM - 1 Like   #144
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It would be helpful if Pentax allowed for different fine focusing adjustments at multiple distances and focal lengths.
12-08-2021, 11:02 AM   #145
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QuoteOriginally posted by ChristianRock Quote
the FA Limited designs were always about leaving a bit of uncorrection and field curvature, to help with bokeh and rendering... people just need to decide what is more important to them.
Exactly. The (D) FA Limiteds were designed with what I (perhaps incorrectly) call "character" firmly in mind, and prioritised over optical perfection.

I love my HD DA Limited primes, and there's definitely some of the FA Limited character to be found in them - but less of it, IMHO...
12-08-2021, 11:33 AM - 1 Like   #146
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QuoteOriginally posted by BigMackCam Quote
Exactly. The (D) FA Limiteds were designed with what I (perhaps incorrectly) call "character" firmly in mind, and prioritised over optical perfection.

I love my HD DA Limited primes, and there's definitely some of the FA Limited character to be found in them - but less of it, IMHO...
I don't see why "character" would be incorrect in this case. Even the swirly bokeh of some lenses might be called "character", although a bad and probably unintentional one.

We know the designer stories for the Limiteds. The D FA 21mm with its special made test barrel for establishing the right bokeh. The FA Limiteds, when Shoji Otake trained the Pentax engineers to see. Evaluating the lens through actual prints.
It doesn't seems the others are bothering themselves with this, with designing a Limited-grade character into a lens. After all, "optical perfection" is easier to sell... and you can still have a pleasant rendering with smooth bokeh.
12-08-2021, 11:42 AM   #147
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I'd reserve "character" for slightly more dubious behaviour that one none the less might appreciate in certain circumstances. Like swirdly, bubbly, flary behavior or interesting colour casts etc.
12-08-2021, 11:43 AM   #148
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Isn't it necessary to have an appropriate subject in order to show the "character" or "pixie dust"?
12-08-2021, 11:47 AM - 1 Like   #149
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QuoteOriginally posted by Kunzite Quote
The D FA 21mm with its special made test barrel for establishing the right bokeh. The FA Limiteds, when Shoji Otake trained the Pentax engineers to see. Evaluating the lens through actual prints.
...
It doesn't seems the others are bothering themselves with this, with designing a Limited-grade character into a lens. After all, "optical perfection" is easier to sell... and you can still have a pleasant rendering with smooth bokeh.
It'll be interesting to see how the D FA21/2.4 Limited fares when it's tested by the multitude of online review sites. "Optical perfection" seems to be the theoretical bar against which lenses are now judged, and I can't think of too many reviewers who will understand the reasons for this lens' performance characteristics... or if they do, they probably won't agree with the design choices; especially on a £1,500 lens
12-08-2021, 11:49 AM   #150
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There's certainly a style to the recent DFA21 samples but it may well be autumn light and vegetation more than actual rendering
Joking aside the do look very good as images. Most of them have a "pull"

I doubt we'll se many reviews of the lens. How many have looked at the DA1650 for instance, or even the DFA85.
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