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05-03-2020, 12:01 PM   #16
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QuoteOriginally posted by stevebrot Quote
Best to do some research before making rash claims. The "K-mount Page" has diagrams for most K-mount lenses and the differences are obvious. See the two links below for lens descriptions including links to the optical diagrams:

D FA 100/2.8 Macro WR | The K-Mount Page

FA 100/2.8 Macro | The K-Mount Page

That fact does not mean you have not had problems with your copy, only that the design is hardly dated or "film-era".



Steve
For sure, many of the old film era macros hold up in the digital age. They were always a different class of lens.

05-03-2020, 12:12 PM - 1 Like   #17
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QuoteOriginally posted by Lowell Goudge Quote
The photo seems impossible. There is a combination of longitudinal CA but it cannot go purple, then green then back to purple.

Where does the image come from
It's from the PCMAG review Pentax D FA 100mm F2.8 Macro WR Digital Cameras - Review 2016 - PCMag UK

For those interested the youtube link shows rather similar full on purple on some tree branches. I agree that the pcmag image is probably with a largish aperture but unfortunately there's no telling. I don't mind if ca is like that wide open but it's important that it goes away when stopping down.

QuoteOriginally posted by stevebrot Quote
Yep...the difference is subject distance. It is not unusual for macro lenses to have mild LoCA at other than close focus that translates to alarming purple fringing (PF) with some sensors in high contrast light. One has to go to an apochromatic design such as the Cosina/Voigtlander 125mm Apo-Lanthar to be completely free of PF ($$$).
That's an interesting observation. All macro shots look near perfect, some of the longer distance ones less so.

It seems most of those who love it, and show excellent examples, (thanks norm etc) shoot the lens as it's intended. Macro or at least close up.

With a telephoto lens you can quite easily avoid sky in your photographs without making an effort. Hence never noticing the issue. For my use of the lens, compressed perspectives and details of architecture I'm very likely to have dark things against sky. I'm looking for a ff da70ltd replacement and the 100mm dfa looked like just the thing. Fringe away below f4 but clean up after.

I'll have to search for more samples

This ephotozine image from here Pentax-D FA 100mm f/2.8 Macro WR Lens Review | ePHOTOzine follow link to see full size image. Looks ok at f6.3 some fringing around the frames but minor enough.
05-03-2020, 12:15 PM   #18
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QuoteOriginally posted by house Quote
It's from the PCMAG review Pentax D FA 100mm F2.8 Macro WR Digital Cameras - Review 2016 - PCMag UK
Did your buy your copy from them?
05-03-2020, 12:16 PM   #19
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QuoteOriginally posted by house Quote
. . It seems most of those who love it, and show excellent examples, (thanks norm etc) shoot the lens as it's intended. Macro or at least close up. . . .
actually a 100mm lens is considered a short telephoto I believe:

QuoteQuote:
What is Focal Length and Which Lens Should I Use?
. . . Normal lens: A focal length that corresponds to the human eye. 50mm, also known as the Nifty Fifty.
Telephto (long focal length): A longer focal length lens than normal, this lens allows one to get close up with being closer. It provides a narrower field of view than a normal lens. Lengths are 85mm to 2000mm.. .

Macro lens: These lenses can be of any flength, but most often are in the normal or short telephoto range of lengths. . . .

What’s the length of a lens that’s telephoto? For a full-frame 35mm camera, any lens longer than the normal 50mm range. The length of this lens can range between 85mm and 2000mm or more. Popular lenses in this range include 85mm, 100mm, 105mm, 135mm, 200mm, or longer. Zoom are typically in the 70-200mm and 150-500mm range.
https://www.colesclassroom.com/focal-length-basics-every-photographer/


Last edited by aslyfox; 05-03-2020 at 12:25 PM.
05-03-2020, 12:21 PM   #20
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QuoteOriginally posted by normhead Quote
Did you buy your copy from them?
I'm only considering the lens. The examples above are from reviews.

I found that the SMC PENTAX-DFA MACRO 1: 2.8 100mm WR Review | Happy site provides a compressed file with all sample images including the fringed out tree. Turns out it was indeed also f2.8. My faith in this lens is being restored.
05-03-2020, 12:22 PM   #21
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QuoteOriginally posted by stevebrot Quote
User Giannclaudio posted a blistering negative review of the DFA 100/2.8 WR Macro a few months ago and from the description there, their copy of the lens is likely damaged or defective.

SMC Pentax-D FA 100mm F2.8 Macro WR Reviews - D FA Prime Lenses - Pentax Lens Reviews & Lens Database
Thanks, Steve. I just read it, and it certainly appears something's not right with his copy. That review isn't representative of my own experiences with this lens.
05-03-2020, 12:31 PM   #22
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QuoteOriginally posted by stevebrot Quote
User Giannclaudio posted a blistering negative review of the DFA 100/2.8 WR Macro a few months ago and from the description there, their copy of the lens is likely damaged or defective.

SMC Pentax-D FA 100mm F2.8 Macro WR Reviews - D FA Prime Lenses - Pentax Lens Reviews & Lens Database


Steve
Yes I did. Shouldn't I been able to express my review of my lens?

Sad to single out someone because his opinion differs to yours.

In the past, I've readed in the forum that the formula is the same as F and FA, and by the number of elements, I thought it was the same. It certainly feels like a film era lens in purple fringing, colour, contrast, saturation, glare, like the film era lens I used to have.

The limiteds (15, 20-40, 35, 70) I have/used to have and my da*50-135 doesn't show that behaviour. Both inside with strobes and outside, the dfa100 image quality looks more akim to the old lenses than the new ones.

Thanks and best regards.

05-03-2020, 12:36 PM   #23
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Looked a bit further into the samples from radojuva.com (seems to do good Pentax reviews, the da 11-18 is nice as well) and unfortunately found this f5.6 image.



So I guess we have to conclude that the differing experiences comes from different use cases.
05-03-2020, 12:51 PM - 2 Likes   #24
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QuoteOriginally posted by house Quote
Looked a bit further into the samples from radojuva.com (seems to do good Pentax reviews, the da 11-18 is nice as well) and unfortunately found this f5.6 image.

...

So I guess we have to conclude that the differing experiences comes from different use cases.
Goodness me... What level of magnification is that?!? The general image quality of that sample is truly awful and looks like it's been enlarged significantly, and certainly above 1:1. Furthermore, those white flowers are so badly exposed that they're completely blown. Honestly, purple fringing in this example is hardly surprising. I've plenty of lenses can manage that
05-03-2020, 01:09 PM   #25
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QuoteOriginally posted by BigMackCam Quote
Goodness me... What level of magnification is that?!? The general image quality of that sample is truly awful and looks like it's been enlarged significantly, and certainly above 1:1. Furthermore, those white flowers are so badly exposed that they're completely blown. Honestly, purple fringing in this example is hardly surprising. I've plenty of lenses can manage that
Yes I zoomed in a lot just to avoid people not seeing it but we're not talking a pixel of five of fringing here. That's a lot more. The character of the fringing blooms out quite a lot and I don't think that's very good news. Some of my da lenses that fringe have a much more manageable thin but strong line. I think this is very difficult to handle in post.
05-03-2020, 01:15 PM - 1 Like   #26
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QuoteOriginally posted by house Quote
This ephotozine image from here Pentax-D FA 100mm f/2.8 Macro WR Lens Review | ePHOTOzine follow link to see full size image. Looks ok at f6.3 some fringing around the frames but minor enough.
From the same ephotozine review is this image, shot at f/5.6:

https://www.magezinepublishing.com/equipment/images/equipment/PentaxD-FA-Mac...1392806347.jpg

Click on the image to pixel peep, then look at the branches. That level of (in this case, green) fringing in a high contrast scenario is about what I'd expect with my own copy at f/5.6 (it would be considerably worse at f/2.8), and perfectly acceptable for this type and class of lens. Your mileage may vary, of course.

QuoteOriginally posted by house Quote
Yes I zoomed in a lot just to avoid people not seeing it but we're not talking a pixel of five of fringing here. That's a lot more. The character of the fringing blooms out quite a lot and I don't think that's very good news. Some of my da lenses that fringe have a much more manageable thin but strong line. I think this is very difficult to handle in post.
That's not been my experience with my own copy of the lens. Certainly, as 100mm macro lenses go, the D FA100 f/2.8 WR is a very good one, and I've not run into significant problems regarding fringing, but my use cases aren't yours. Given the sample images you're looking at and your doubts, I think you're going to need to either borrow or rent the lens to make your own mind up, or else pick something different at the outset.

Another possibility to consider would be Tamron's older 90mm f/2.8 macro, which is available in K-mount. I have it in Minolta AF / Sony A-mount, and really like it...

Last edited by BigMackCam; 05-03-2020 at 01:22 PM.
05-03-2020, 01:40 PM - 3 Likes   #27
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QuoteOriginally posted by house Quote
Yes I zoomed in a lot just to avoid people not seeing it but we're not talking a pixel of five of fringing here. That's a lot more. The character of the fringing blooms out quite a lot and I don't think that's very good news. Some of my da lenses that fringe have a much more manageable thin but strong line. I think this is very difficult to handle in post.
The good news is that well corrected lenses are designed so that all colors are in in focus at the (same) plane of focus. The flowers are out of focus and overexposed as well. Pentax lenses are not corrected for that. Maybe Coke bottles are....
05-03-2020, 01:50 PM   #28
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Another example photo you might want to check out on Flickr, taken with the D FA100/2.8 WR at f/6.3 (with plenty of high contrast cable vs sky action ) by our very own forum member @larrymc ... you can enlarge it twice and see just how little fringing there is. Of course, he may have used the CA removal tool in his post-processing software, but even if he did, no harm done

Vote for Me! SIC August 6 | Larry Mc | Flickr
05-03-2020, 01:50 PM - 1 Like   #29
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This entire thread leaves me puzzled as well. I have both the DFA 100 and DFA 100 WR. I can't recall ever seeing this from either of the lenses. No I have to go have a look at this. Still, I've always found both of those lenses to produce wonderful images, although the rounded blades on the 100 WR has a much better bokeh. Otherwise, I don't know what else to say here. Still puzzled.
05-03-2020, 01:58 PM - 1 Like   #30
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QuoteOriginally posted by Gianclaudio Quote
Yes I did. Shouldn't I been able to express my review of my lens?
And you also shouldn't be bothered is other people differ.

What you should be doing is understanding "your copy" is not like many other copies.

---------- Post added 05-03-20 at 04:59 PM ----------

QuoteOriginally posted by BigMackCam Quote
Another example photo you might want to check out on Flickr, taken with the D FA100/2.8 WR at f/6.3 (with plenty of high contrast cable vs sky action ) by our very own forum member @larrymc ... you can enlarge it twice and see just how little fringing there is. Of course, he may have used the CA removal tool in his post-processing software, but even if he did, no harm done

Vote for Me! SIC August 6 | Larry Mc | Flickr
The issue in the image is why isn't there purple fringing? I guarantee you taken with my F 70-210 there would be.
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