[mikesbike]

Thanks for all responses. It's images like this that have me concerned.



????? ?????-????? SMC PENTAX-DFA MACRO 1:2.8 100mm WR - YouTube

Wow! I like it. You can see the electricity going through the wire! (your photo, not the video)

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Last edited by mikesbike; 05-04-2020 at 01:10 PM.

[Pål Jensen]

Shooting silhouetted branches (or TV aerials ) against a brightly lit sky is going to be a challenge for any lens...

But who take such images and keep them? Whats the point of searching for faults in lenses in images that are technically and artistically hopeless and without value?
The least of these images problems is fringing...

[mikesbike]

Maybe the new Pentax 85mm f/1.4 will turn out to do well in the fringing department.

As others have said, it might be difficult to find a lens devoid of this phenomenon completely under the conditions most likely for it to occur. In this case, most people never have the problem in using the DFA 100mm macro as a macro lens, not predominantly for distant shots of subject matter against a strongly contrasting sky. I am wondering if there is in-camera correction of this issue for this lens?

[BigMackCam]

But who take such images and keep them? Whats the point of searching for faults in lenses in images that are technically and artistically hopeless and without value?
The least of these images problems is fringing...

Who are we to say what's of artistic value and what isn't? It's down to the photographer, I guess. I can imagine a high-key shot of the sun shining through trees almost directly at the camera... that could be a valid artistic choice where fringing might be exacerbated. Frankly, any artistic desire the photographer has is valid. Whether the equipment is well suited or even capable of delivering to that is another matter...

[house]

But who take such images and keep them? Whats the point of searching for faults in lenses in images that are technically and artistically hopeless and without value?
The least of these images problems is fringing...

I'm not a great photographer. It's not my main interest. However my photographs are published by a dozen of magazines, art museum catalogues, books, have been on display at one of the Giardini Pavillions at the Venice biennale etc. While you might judge them without having seem them others that have seen them judge differently.

[Pål Jensen]

Really? Power lines and branches in front of an overexposed sky? Never seen such images published anywhere.
Show us a good, publishable image taken with a well renowned lens that show visible fringing and I'll be convinced.

---------- Post added 05-04-20 at 11:02 PM ----------

Who are we to say what's of artistic value and what isn't? It's down to the photographer, I guess. I can imagine a high-key shot of the sun shining through trees almost directly at the camera... that could be a valid artistic choice where fringing might be exacerbated. Frankly, any artistic desire the photographer has is valid. Whether the equipment is well suited or even capable of delivering to that is another matter...

If any artistic desire is valid then fringing is valid and of value as it might be an artistic intention.
It is symptomatic that these fringing shots we see are deliberate provocations designed to invoke fringing in impossible situation that the lenses are not designed for. Ordinary images, the one destined to be kept, are not valid it seems for judging lenses....

[MossyRocks]

My DFA 100/2.8 macro is one of my most used. In harsh situations I can get it to purple fringe out to about f/5.6 but it has to be pretty harsh as in I am shooting into the sun or have something bright in front of a darker subject in full sun. Out of curiosity I tried it for astro and there the rumors are true about it being a purple fringing monster and unusable for that but there you have point sources of light against a black background. For astro it is almost as bad as my Vivitar Series 1 135mm f/2.3 which is another one to not do astro with.

[house]

My DFA 100/2.8 macro is one of my most used. In harsh situations I can get it to purple fringe out to about f/5.6 but it has to be pretty harsh as in I am shooting into the sun or have something bright in front of a darker subject in full sun. Out of curiosity I tried it for astro and there the rumors are true about it being a purple fringing monster and unusable for that but there you have point sources of light against a black background. For astro it is almost as bad as my Vivitar Series 1 135mm f/2.3 which is another one to not do astro with.

doesn't this just mean that the dfa has more fringing capacity than many lenses? Just that some dont trigger it whilst others do? Do you have other modern glass that reacts like that to astro.

[MossyRocks]

doesn't this just mean that the dfa has more fringing capacity than many lenses? Just that some dont trigger it whilst others do? Do you have other modern glass that reacts like that to astro.

Most of what I own lens wise is old. I own only 4 auto focus prime lenses and of those only 1 was a digital era design. As far as my modern (auto focus) prime lenses go:
I haven't used the FA 77 ltd for astro so I dont' know how it performs I probably should but haven't figured out a good target to try it on.
The DA 35mm f/2.4 is barely acceptable wide open but if you run it at f/4 it is pretty good
The DFA 100/2.8 macro needs to be stopped down so much that that it becomes pointless for doing astro because running it at f/8 is dumb
The Sigma 300mm f/4 APO Macro (film era lens with the awful zen barrel coating) this lens is great good enough wide open and great at f/5.6

As far as my other lenses and astro:
S-M-C 17mm f/4 Fisheye takumar - A hot mess for astro don't bother. It is slow and needs to be stopped down to near f/11 to not suck for astro, so it sucks for astro
S-M-C 28mm f/3.5 Takumar - Not bad should be run at f/5.6 would be nice if it was faster
S-M-C 50mm f/1.4 Takumar - Run it at 2.8 for astro and it is golden
SMC A 50mm f/1.2 - useless wide open but gets good at f/1.8 and really good at f/2
Vivitar Series 1 135mm f/2.3 - purple fringes like mad even worse than the DFA 100/2.8 macro needs to be stopped down to at least f/8.
S-M-C 200mm f/4 Takumar - Acceptable wide open best if run at f/5.6, this and the K or M version are some of the more sought after starter astro lenses for good reason
S-M-C 300mm f/4 Takumar - Needs more stopping down than the 200/4 and has purple fringing but it isn't too bad
SMC A* 400 f/2.8 ED [IF] - Pretty good wide open with some light coma, stopped down to f/3.5 it is perfect

I have a couple of older zooms that I don't use much for astro but I have used my old Tokina 28-70mm f/2.8-4.3 at the wide end and it isn't bad at f/4 but does have some coma with really bright stars. I haven't used my SMC A 70-210 f/4 for astro so I can't speak to it. I also have my "cub scout" lens which I used when I need to cover almost my full focal length range with one lens so the Tamron 28-300mm F3.5-6.3 XR Di AF lens I own isn't one I have taken out for astro and don't plan on it.

[house]

Most of what I own lens wise is old. I own only 4 auto focus prime lenses and of those only 1 was a digital era design. As far as my modern (auto focus) prime lenses go:
I haven't used the FA 77 ltd for astro so I dont' know how it performs I probably should but haven't figured out a good target to try it on.
The DA 35mm f/2.4 is barely acceptable wide open but if you run it at f/4 it is pretty good
The DFA 100/2.8 macro needs to be stopped down so much that that it becomes pointless for doing astro because running it at f/8 is dumb
The Sigma 300mm f/4 APO Macro (film era lens with the awful zen barrel coating) this lens is great good enough wide open and great at f/5.6

As far as my other lenses and astro:
S-M-C 17mm f/4 Fisheye takumar - A hot mess for astro don't bother. It is slow and needs to be stopped down to near f/11 to not suck for astro, so it sucks for astro
S-M-C 28mm f/3.5 Takumar - Not bad should be run at f/5.6 would be nice if it was faster
S-M-C 50mm f/1.4 Takumar - Run it at 2.8 for astro and it is golden
SMC A 50mm f/1.2 - useless wide open but gets good at f/1.8 and really good at f/2
Vivitar Series 1 135mm f/2.3 - purple fringes like mad even worse than the DFA 100/2.8 macro needs to be stopped down to at least f/8.
S-M-C 200mm f/4 Takumar - Acceptable wide open best if run at f/5.6, this and the K or M version are some of the more sought after starter astro lenses for good reason
S-M-C 300mm f/4 Takumar - Needs more stopping down than the 200/4 and has purple fringing but it isn't too bad
SMC A* 400 f/2.8 ED [IF] - Pretty good wide open with some light coma, stopped down to f/3.5 it is perfect

I have a couple of older zooms that I don't use much for astro but I have used my old Tokina 28-70mm f/2.8-4.3 at the wide end and it isn't bad at f/4 but does have some coma with really bright stars. I haven't used my SMC A 70-210 f/4 for astro so I can't speak to it. I also have my "cub scout" lens which I used when I need to cover almost my full focal length range with one lens so the Tamron 28-300mm F3.5-6.3 XR Di AF lens I own isn't one I have taken out for astro and don't plan on it.

That probably a useful list. Perhaps it deserves a thread, just for people on the internet to find?

Am I reading it right though. Does it mean that the DFA 100mm is indeed more fringe prone, in the astro scenario, than most of your vintage lenses?
The astro scenario is an extreme one but it does show how badly the lens can fringe. Even if it will be relatively less in more normal scenarios it will be worse than say the S-M-C 28mm f/3.5 in the same normal scenario.

[MossyRocks]

Am I reading it right though. Does it mean that the DFA 100mm is indeed more fringe prone, in the astro scenario, than most of your vintage lenses?

I would say yes but keep in mind that this is as extreme as one can get. True point sources of light against basically a true black background

I would say that under normal scenarios it is probably less as I have been able to more easily get fringing out of my other old lenses. You brought up the S-M-C 28mm f/3.5 as an example and I would say in more normal circumstances the 28mm probably fringes more than the DFA 100/2.8 macro. Keep in mind there is sample variation and apart from my 28/3.5 I have had one copy of each lens. The 28/3.5 I have owned 2, one was a bit worn when I got it and after 20 years of heavy use after that there was a lot of slop in the helicoid so that the focus would change noticeably so I bought another copy of it. and it has been just as good of a performer but without the slop from being worn out.

Also the biggest thing is to avoid cases where fringing would be a problem and this should be taken as good general advice anyway as it usually indicates you are shooting in strong midday sun with things being overexposes in the bright highlights next to things in deep harsh shadows so the image would already have a lot going against it to begin with. I try to avoid shooting in those situations because the pictures kind of suck anyway.

[Wheatfield]

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.

That isn't an image so much as it's visual garbage.
I haven't used the D FA 100mm AW Macro for much other than macro work, but I've found it to be very, very good indeed. The below picture would be a trial for any lens. It was stopped down to f/8. The few images I've used it for pictorial work have been fine, but not images that would be especially stressful for a lens.
The image of the power lines looks more like a deliberately set up hit piece than anything else.

---------- Post added May 5th, 2020 at 12:16 PM ----------

That "long way to adjust focus" is usually in the near focus area for macro lenses optimized for fine tuning focus for macro distances. They are usually ultrafast focusing in the areas used for general photography due to the small focus throw in the area from a few meters to infinity....

It can be an annoyance if the lens starts to hunt as the throw from infinity to 1:1 is quite long, but in the range from a half meter to infinity, the throw is very short, and the lens does focus fairly quickly.

[house]

The few images I've used it for pictorial work have been fine, but not images that would be especially stressful for a lens.
The image of the power lines looks more like a deliberately set up hit piece than anything else.

The image is from a review. Usually a lens review is about finding the stress points for a lens and reporting on them. However as I've mentioned I photograph buildings (and spaces). A short tele such as 100mm will be used to either 1. capture the building from very far away. 2. Grap tighter crops of sections of the building. 3. Take details of things beyond reach such as eaves, details of roofs, windows etc. All but 2 will be guaranteed to have branches, ironmongery, copings or other dark details against often bright sky. I have to work with the conditions of the visit and preferably come away with a sequence of images covering various aspects. I will often have one visit this lifetime as pre covid I've photographed buildings on four continents.

I have to say people seriously lack imagination if they despite my detailed descriptions of requirements can't believe anyone can photograph anything but dogs, mushrooms, flowers and sunsets. I've explained my requirements quite a few times and there are way to many posts that seem to suggest I should just take photographs of ... dogs, mushrooms, flowers or sunsets... and avoid these high contrast situation... I don't know what to say. I spelled out the conditions in the OP.

That's a well handled back lit image of ... a flower... It seems that perhaps something happens at when you focus far away, none of the problematic examples are closeups.

[Wheatfield]

The image is from a review. Usually a lens review is about finding the stress points for a lens and reporting on them. However as I've mentioned I photograph buildings (and spaces). A short tele such as 100mm will be used to either 1. capture the building from very far away. 2. Grap tighter crops of sections of the building. 3. Take details of things beyond reach such as eaves, details of roofs, windows etc. All but 2 will be guaranteed to have branches, ironmongery, copings or other dark details against often bright sky. I have to work with the conditions of the visit and preferably come away with a sequence of images covering various aspects. I will often have one visit this lifetime as pre covid I've photographed buildings on four continents.

I have to say people seriously lack imagination if they despite my detailed descriptions of requirements can't believe anyone can photograph anything but dogs, mushrooms, flowers and sunsets. I've explained my requirements quite a few times and there are way to many posts that seem to suggest I should just take photographs of ... dogs, mushrooms, flowers or sunsets... and avoid these high contrast situation... I don't know what to say. I spelled out the conditions in the OP.

That's a well handled back lit image of ... a flower... It seems that perhaps something happens at when you focus far away, none of the problematic examples are closeups.

That was shot from a few meters, well out of the macro range, and is of a very tough subject, being heavily backlit. I'm not suggesting what you should, or shouldn't take pictures of, but I would suggest that rather than being dismissive of people who are trying to help you, perhaps have a look at the help they are trying to give. It's a good way to give people a reason to help you in the future. If I was going to get fringing on that lens, the picture I showed would have it in spades. I apologize that it isn't a backlit tree branch.
Sometimes we have to take the help that is offered. Sometimes we don't get what we want, but if we try real hard, we get what we need.

[BigMackCam]

doesn't this just mean that the dfa has more fringing capacity than many lenses?

Does it mean that the DFA 100mm is indeed more fringe prone, in the astro scenario, than most of your vintage lenses?
The astro scenario is an extreme one but it does show how badly the lens can fringe.

With respect, in light of all the advice you've received - from amongst which just one user reported terrible fringing, whilst all others gave much more positive feedback - it almost seems like you want someone else to say this lens has a fringing problem It hasn't - at least, not especially so... not once it's stopped down a bit.

It fringes more than some lenses, and less than some others. Even for your use case, by the apertures you're especially interested in - f/5.6 and narrower - the fringing is negligible and very easily correctable (as I demonstrated in the test shots I provided).

It's really difficult to give better information than that, because unless someone has taken the same shots of the same subjects in the same lighting conditions using a variety of lenses including the DFA100/2.8 WR, it's almost impossible to compare them. For instance, I already mentioned the Tamron 90mm f/2.8 Di Macro lens a couple of times as an alternative that you might consider. I can tell you that it also produces fringing in the right conditions... but since I haven't shot the two lenses side by side, I can't honestly say whether the Pentax is better or worse than the Tamron in this respect. Neither is bad, and both are easily corrected at the apertures you require.

Aside from the DFA100, there's really not much choice of AF prime lenses in K-mount at or around this focal length, and none are apochromats - so they'll all suffer from axial CA to some extent. There are variable aperture zooms that cover the range, but they're unlikely to perform favourably at f/5.6 - 6.3. Of course, there some faster, bigger, heavier zooms that also cover the range. They may be worth looking at, if you don't mind the size and weight.

Also the biggest thing is to avoid cases where fringing would be a problem and this should be taken as good general advice anyway as it usually indicates you are shooting in strong midday sun with things being overexposes in the bright highlights next to things in deep harsh shadows so the image would already have a lot going against it to begin with. I try to avoid shooting in those situations because the pictures kind of suck anyway.

That's probably the best advice of any in this whole thread