[reh321]

Why given the same sensor on the K-5 and D7000 is the max output for the D7000 come in 200 lw/ph ahead of Pentax even testing the same lens on different bodies?

At least the 'accelerator' isn't involved.

[monochrome]

?

You don't use one, you're a brand jumper, Winder!

Its MTF curves show it's better than all those lenses you mention (and have probably also never used) and better than those Sonys you have actually paid for and use!

Your repeatedly misguided Pentax bashing to Pentax owners on a Pentax forum speaks volumes of your judgement, I'm afraid.

I boriscletoed @Winder ages ago. My Forum experience improved immediately. Unfortunately he seems to have wound everyone up on this thread.

[normhead]

Well... did he really?
Roger Cicala tests new Sony FE 135mm F1.8 GM, confirms 'insanely good' MTF results: Digital Photography Review



Well, APO summicron has almost no CA issues (seems design priorities were different than in case of Noctilux). Plus it's light and compact (300 grams, 8 elements in 5 groups). Also, I'd wager there's a point where relation between price and quality of the lens simply becomes exponential (and it's not just red dot tax). Diminishing returns for some. For others, best possible look in such compact package.

I started looking at images, found a few results, and a couple of images to illustrate my point. I'm not getting much in return here. Opinions are nice but evidence is important if you're trying to make a conclusive case. I saw nothing that would inspire me to buy the Summicron, or even to think it might be better than my DA* 55 1.4. To me, the 50 Sumicron looks like FA ltd. tech. I also would compare it to the 77 ltd.

If you look down at the comments on the 50mm tests quoted, you'll see why I said he was no longer testing, it was because he said he was no longer testing. Not my fault he changed his mind.

[BarneyL]

Opinions are nice but evidence is important if you're trying to make a conclusive case.

You're saying that like I didn't provide any. You just didn't find it convincing. Which is fine.

I saw nothing that would inspire me to buy the Summicron, or even to think it might be better than my DA* 55 1.4.

Totally OK. It's not like I'm a Leica affiliate and get a kickback each time someone drops 8 grand on a lens.

I used that example to counter the point you made earlier:

Light but optically excellent doesn't exist.

Based on flickr images, you said it was a toss up between Summicron and DFA* 50.

Good, but better than the Pentax DFA, looks like pretty much a toss up to me

So assuming D-FA is optically excellent, APO summicron is optically excellent as well.
However, APO summicron is much smaller and lighter than DFA 50.

Therefore, light but optically excellent does exist.

Whether it's worth the money, well, is another issue.

Personally, I haven't seen real life prints from APO Summicron yet. But I've seen some from 50 Summilux ASPH. If I ever had money to buy a Leica, that would be a lens of my choosing.

[repaap]

Umm, isn’t those leicas APSH lenses? Not weather proof? This reduces size, as being FF lens (DFA*50/1,4) it has to be bigger. Given that those Leica is 2-4 times more exspensive, it has to be sharp. Throw in Zeiss OTUS and you have some sort of same league. As it is FF lens too.

[Kunzite]

However, APO summicron is much smaller and lighter than DFA 50.

APO Summicron 50mm f/2? Which is:
- f/2 instead of f/1.4
- manual focus (no ring-type SDM)

Besides this - I can't find pixel-peeping reviews for this lens - there are other factors to consider:
- vignetting. One of the reasons the D FA* is so big is to control vignetting. The Leica has what, 2 stops after baking the RAW? (according to diglloyd)
- center to corner sharpness. The D FA* is quite good in this regard (and once again, necessarily larger because of it).

[Rondec]

I do think it is interesting that there are so many folks who show up to disparage the Pentax DFA *50 (and for that matter the K-1 II) who haven't used them. Clearly the point of the DFA *50 is wide open performance and in that, it delivers in spades. If you are satisfied with decent sharpness at f2 or f2.8 then there are a bundle of lenses out there that will satisfy.

For what it is worth, ephotozine has tested a number of the top end lenses. These include the DFA *50: HD Pentax-D FA 50mm f/1.4 SDM AW Lens Review - Performance | ePHOTOzine and the Sony Planar FE 50 f1.4 Zeiss Planar T* FE 50mm f/1.4 ZA Lens Review | ePHOTOzine and the Canon 50 f1.2 Canon EF 50mm f/1.2L USM Lens Review | ePHOTOzine (This is not the 50 f1.2 released for the RP). The graphs show significantly better edge performance for the DFA lens up f4 or so. In addition, the CAs for the Sony and Canon are comparable to the DFA *50 -- there is no significant difference.

The problem is that DP Review doesn't measure anything, but that doesn't stop them from commenting on it. A comment about high levels of CA with the Pentax lens, but not mentioning it with other tested lenses implies that LoCA isn't present with most fast aperture lenses except for Pentax. Such is not the case and the lenses that eliminate LoCA have apochromatic lens groups that raise the price of the lens dramatically (see Leica 50mm f2 Summicron). It is possible with in camera corrections to correct some of this and certainly Sony does this, but regardless, I think we can say about the DFA *50 that it is (a) sharper than all of the other 50s in its price range and (b) there is no testing that has actually shown more LoCA with the DFA * lens than with other similar lenses.

(The DP Review article which generated this buzz had a significantly higher portion of the sample Pentax shots in strongly backlit situations than with Sony or Sigma).

[BarneyL]

APO Summicron 50mm f/2? Which is:
- f/2 instead of f/1.4
- manual focus (no ring-type SDM)

According to results from Roger's tests, at F/2 it is still better than Sigma A closed down one stop where it comes to resolution (although that probably is visible at pixel peeping level only). But yes, in general, the bokeh quality at F/2 might be a bit lacking compared to F/1.4. That's why I personally prefer Summilux Asph. Still very sharp up to corners with truly awesome bokeh. And weighs 330 grams.


Sure, it is manual focus. But there are also other MF lenses that weigh a ton for similar performance, like Otus Apo Distagon.

Besides this - I can't find pixel-peeping reviews for this lens - there are other factors to consider:
- vignetting. One of the reasons the D FA* is so big is to control vignetting. The Leica has what, 2 stops after baking the RAW? (according to diglloyd)
- center to corner sharpness. The D FA* is quite good in this regard (and once again, necessarily larger because of it).

I'd like to ask for vignetting measurements for D FA*. Just curious. Also, two stops of vignette for F/2 lens, especially rangefinder lens (where a lot of users still shoot analog) sounds a bit excessive. Too bad there aren't many tests.

The problem is that DP Review doesn't measure anything, but that doesn't stop them from commenting on it. A comment about high levels of CA with the Pentax lens, but not mentioning it with other tested lenses implies that LoCA isn't present with most fast aperture lenses except for Pentax.

This is why I'm hoping for a test made by Lenstip. These guys aren't perfect of course; IMO pay too much attention to resolution figures (with pretty ad hoc 'usable image quality' level, but they have consistent methodology. They don't provide numbers for LoCA, but at least they have a strict standard for comparison in controlled environment.


Here's Sigma A 50 test for CA:
Sigma A 50 mm f/1.4 DG HSM review - Chromatic and spherical aberration - LensTip.com

[normhead]

You're saying that like I didn't provide any. You just didn't find it convincing. Which is fine.

You provided no conclusive evidence.
Any conclusion would require multiple assumptions.

My conclusion based on the same facts would be, better to keep an open mind than declare one the winner.

Based on flickr images, you said it was a toss up between Summicron and DFA* 50.

The reason for buying the DFA 50 1.4, is CA control and edge to edge sharpness. If you want those features the DFA appears to be better. For outright centre sharpness, we have nothing definitive but it's possible that the Sumicron might be marginally better, but any difference will be observable only pixel peeping. SO, it's a toss up which you might prefer. Many prefer the center sharp FA ltds. which appear to be more mike the Summicron. The DFA 50 1.4 is in a different class.
I'm pretty sure a better photographer would have produced a better image with the Sumimaron than the wone I found, but there are very few images for either lens. Choice was limited. In my mind there's insufficient evidence of a clear winner, but the choice can be made by what you prefer in a lens. I doubt given a sample of ten buyers all 10 would choose one or the other. That of course ignores the price difference. With the price difference I'd expect the Pentax to outsell the Leica 10:1 (amongst discerning photographers) at least, probably a lot more.

Those would be my final thoughts on the topic.

[Rondec]

According to results from Roger's tests, at F/2 it is still better than Sigma A closed down one stop where it comes to resolution (although that probably is visible at pixel peeping level only). But yes, in general, the bokeh quality at F/2 might be a bit lacking compared to F/1.4. That's why I personally prefer Summilux Asph. Still very sharp up to corners with truly awesome bokeh. And weighs 330 grams.


Sure, it is manual focus. But there are also other MF lenses that weigh a ton for similar performance, like Otus Apo Distagon.




I'd like to ask for vignetting measurements for D FA*. Just curious. Also, two stops of vignette for F/2 lens, especially rangefinder lens (where a lot of users still shoot analog) sounds a bit excessive. Too bad there aren't many tests.



This is why I'm hoping for a test made by Lenstip. These guys aren't perfect of course; IMO pay too much attention to resolution figures (with pretty ad hoc 'usable image quality' level, but they have consistent methodology. They don't provide numbers for LoCA, but at least they have a strict standard for comparison in controlled environment.


Here's Sigma A 50 test for CA:
Sigma A 50 mm f/1.4 DG HSM review - Chromatic and spherical aberration - LensTip.com

Pentax Forums measured vignetting for the DFA *50 at about 1.5 EVs wide open. HD Pentax-D FA* 50mm F1.4 SDM AW Review - Vignetting | PentaxForums.com Reviews

---------- Post added 06-10-19 at 08:14 AM ----------

According to results from Roger's tests, at F/2 it is still better than Sigma A closed down one stop where it comes to resolution (although that probably is visible at pixel peeping level only). But yes, in general, the bokeh quality at F/2 might be a bit lacking compared to F/1.4. That's why I personally prefer Summilux Asph. Still very sharp up to corners with truly awesome bokeh. And weighs 330 grams.


Sure, it is manual focus. But there are also other MF lenses that weigh a ton for similar performance, like Otus Apo Distagon.




I'd like to ask for vignetting measurements for D FA*. Just curious. Also, two stops of vignette for F/2 lens, especially rangefinder lens (where a lot of users still shoot analog) sounds a bit excessive. Too bad there aren't many tests.



This is why I'm hoping for a test made by Lenstip. These guys aren't perfect of course; IMO pay too much attention to resolution figures (with pretty ad hoc 'usable image quality' level, but they have consistent methodology. They don't provide numbers for LoCA, but at least they have a strict standard for comparison in controlled environment.


Here's Sigma A 50 test for CA:
Sigma A 50 mm f/1.4 DG HSM review - Chromatic and spherical aberration - LensTip.com

ephotozine measure the difference between the Sigma loCA and Pentax at a little less than .5 pixels. It also shows significantly less border resolution with the Sigma 50 art up to f4. I guess it is up to each photographer to balance their needs for sharpness versus the fear of LoCA severely damaging photographs. In my mind, sharpness and better in focus to out of focus transitions probably trumps the other, but clearly photographers differ on the subject. I just have a hard time imagining .5 pixels of LoCA being the make or break of most photographs.

Sigma 50mm f/1.4 DG HSM Art Lens Review | ePHOTOzine

[Kunzite]

I'd like to ask for vignetting measurements for D FA*. Just curious.

-1.3EV at f/1.4 and f/2, after which it stays at f/1.1 - says ephotozine.

The thing is, Leica must follow the same laws of optics as everyone else. At most, they can afford tighter tolerances - by both not having AF and using a more expensive production process. I would not assume they can achieve compactness with no compromise whatsoever.
OTOH, their Summilux SL 50mm f/1.4 is huge.

[Wheatfield]

I do think it is interesting that there are so many folks who show up to disparage the Pentax DFA *50 (and for that matter the K-1 II) who haven't used them. Clearly the point of the DFA *50 is wide open performance and in that, it delivers in spades. If you are satisfied with decent sharpness at f2 or f2.8 then there are a bundle of lenses out there that will satisfy.

For what it is worth, ephotozine has tested a number of the top end lenses. These include the DFA *50: HD Pentax-D FA 50mm f/1.4 SDM AW Lens Review - Performance | ePHOTOzine and the Sony Planar FE 50 f1.4 Zeiss Planar T* FE 50mm f/1.4 ZA Lens Review | ePHOTOzine and the Canon 50 f1.2 Canon EF 50mm f/1.2L USM Lens Review | ePHOTOzine (This is not the 50 f1.2 released for the RP). The graphs show significantly better edge performance for the DFA lens up f4 or so. In addition, the CAs for the Sony and Canon are comparable to the DFA *50 -- there is no significant difference.

The problem is that DP Review doesn't measure anything, but that doesn't stop them from commenting on it. A comment about high levels of CA with the Pentax lens, but not mentioning it with other tested lenses implies that LoCA isn't present with most fast aperture lenses except for Pentax. Such is not the case and the lenses that eliminate LoCA have apochromatic lens groups that raise the price of the lens dramatically (see Leica 50mm f2 Summicron). It is possible with in camera corrections to correct some of this and certainly Sony does this, but regardless, I think we can say about the DFA *50 that it is (a) sharper than all of the other 50s in its price range and (b) there is no testing that has actually shown more LoCA with the DFA * lens than with other similar lenses.

(The DP Review article which generated this buzz had a significantly higher portion of the sample Pentax shots in strongly backlit situations than with Sony or Sigma).

^^^^^^This^^^^^^^
People will gripe about anything I guess. They need to get a life and get off Twitter for a while and let their frontal lobe recover.
One thing I’ve noted is the complainers haven’t used the lens, and are doing a Ken Rockwell on it. DPReview did what can only be looked at as a hit piece on it. Or at least they tried.
They found scenes that were much more difficult than anything they have applied to any other lens to try to make it fail, and frankly, they failed. This is typical of a DPR. They are shamelessly biased towards their advertisers and have been caught out numerous times faking results.
In their test of the D FA 50, they went so far as to describe the out of focus blur from a green chain link fence as LoCa. They moved the yardsticks from bias to outright lying with that one.
Out of curiosity, why are we comparing the Pentax lens to an ancient design rangefinder lens that is a stop slower? This sort of thing shows the same sort of stupid bias that DPReview shows. Let’s compare an apple to a banana and complain that the banana isn’t an apple. What, are we fourteen or something? It’s just really dumb to try to pull that sort of stuff off in a room full of adults.
It’s like little kids who didn’t get exactly what they wanted for Christmas, while their big brother did. They didn’t get exactly what they wanted so they are going to have tantrums until they do.
They should consider growing up instead.

---------- Post added 06-10-19 at 09:11 AM ----------

-1.3EV at f/1.4 and f/2, after which it stays at f/1.1 - says ephotozine.

The thing is, Leica must follow the same laws of optics as everyone else. At most, they can afford tighter tolerances - by both not having AF and using a more expensive production process. I would not assume they can achieve compactness with no compromise whatsoever.
OTOH, their Summilux SL 50mm f/1.4 is huge.

This is what the diaper brigade should be comparing the Pentax lens to. But they won’t because it doesn’t fit the narrative they are trying to invent.

[Kunzite]

They found scenes that were much more difficult than anything they have applied to any other lens to try to make it fail, and frankly, they failed. This is typical of a DPR.

Like when they "tested" the Pixel Shift with moving water (and inadequate software)?

[Wheatfield]

Like when they "tested" the Pixel Shift with moving water (and inadequate software)?

There is nothing like not reading the manual to make oneself look like a retard. Or worse, they did read the manual and did their moving water test anyway. I’m quite certain that the clowns on DPR are all drunk before 8:00 am and stay that way until they pass out.

[monochrome]

DPR reviews of Pentax products are just Clickbait and we’re the hapless perch. They hook us. Every. Time.