[awscreo]

Actually it's not, but I had decided not to go there in my reply. I am one of the people performing lens reviews for pentaxforums, and an by trade an optical designer with a PhD in optics It would hijack the thread even more to go into details of how lenses are tested and how I build my opinion, but reading reviews will give you an idea. There's a subjective (meaning, non-measurable) part to it, sure, based on my experience with the lenses and looking at how they perform in various situations, the level of detail they deliver, how one compares to the other, but for the most part it's quantitative.



What they do is : verify that a particular copy of a particular lens, on a particular camera, is sharp.

What they SAY is : that lens design compares in such-and-such way with all those other lens designs from all those other manufacturers, and our conclusions are general and applicable in all cases. and they substitute "sharp" with .good" in their conclusions.



The 70-200 is an astounding lens. If not for the size, I would have considered replacing the 60-250 with it, and that's saying something. But I wouldn't say it has pixie dust.



I fully agree with that analysis.

Is it not possible to just take dxo's pure numbers and ignore their opinion? They also measure other things, just like any other review website - vignetting, CA, distortion, light transmission etc, but they have a massive database and an easy web interface to compare lenses, which makes them a good starting point to research a new lens. Granted, they mainly concentrate on canikon, and naturally pentaxforum has more overall reviews (although a lot of them are user reviews, so not really scientific) for Pentax related gear.

In any rate, I don't know you personally, and I tend to take online opinions with a grain of salt (as I'm sure most of the people do). I'm not denying 77s qualities, I do not posses the lens myself. I'm merely expressing skepticism that it out resolves the k-1s sensor, as far as I'm aware only few lenses managed to get to that point - Zeiss Otis and Sigma Art 85, both very recent, highly corrected, quite expensive (in Zeiss case very expensive) modern lenses. If 77s is secretly on the same sharpness level, then I will definitely look at buying one ASAP.

[Nicolas06]

Pentax is not going to release any compact lenses anymore despite releasing compact KP and heavily promoting it with Limited lenses

Excuse me but that's pure marketing propaganda.

I think KP is nice as the first non flag ship camera to almost match K3 in term of performancen but it also match its bulkiness.

The KP has the same dimensions as K3/K3-Ii the previous flagship. It is a bit lighter true but basically like a K5, previous generation flagship. It is heavier/bigger than the previous non flagship cameras of the past years: KS1, KS2, K70, K50...

They can't get arround the K-mount + mirror box, that's a given. But the camera could be significantly smaller/lighter if they wanted; At least like a KS1, likely smaller.

While I think that Pentax keep it DSLR reasonably sized, they tend to make them heavy and don't make them by any means small and the KP is just getting a marketing label of what was standard for the 10 past camera released by Pentax.

As for KP being a sign of new small lenses for the FF or even APSC, I fail to see it. For all we know they could decide to not release a new DAltd for the next 5 years and introduce only big/heavy FF lenses keeping FAltds, FA35 and FA50 as the small light FF primes again for the next 5 years. That would look perfectly reasonable, in particular if kenspo is right that the priority of most people will to pay for them prefer huge/heavy perfect lenses overs diminutive FA ltds.

They can decide to introduce compact FF lenses and renew the DA line later on as APSC is fully covered and recently renewed with the HD DA ltds and FF has legendary ltds.

I just think we all project our desires or fears onto Pentax. And is it perfectly understandable that if you want reasonably sized FF lenses bellow 31mm or past 100mm that you could be worried. In APSC, there DA15 in UWA and there FA77 or DFA100 that with the crop factor cover up to 150mm FF equiv and that are quite reasonably sized. But on FF no reasonably sized lens was released yet except 28-105.

[Doundounba]

Your three categories are - pros, review snobs and test chart junkies. In what world does a new wide standard lens can only be appealing to those? BTW, a pro can be a review snob and a test chart junkie, now your categories are all mixed up?

Seeing as you are referencing dxo in other posts, and the term "test chart jockey" generated such an epidermic reaction - even going so far as your freudian slip into test chart junkie, I'm not too inclined to think my categorization is off the mark. BTW, to me, a "pro" is someone who doesn't just go off test charts or reviews, but, in his or her areas of core expertise, is good enough (and confident enough) to make up their own mind based on personal, real-world experience. Test charts and reviews can help, but never substitute for a pro's own judgment. So a real pro can't be a review snob - unless he/she wrote the review. All this is IMHO, of course.

People can find all sorts of reasons to get this lens, and actually they don't even need any reasons (if they can afford it) because everyone pays for their own gear and its not anyone's place to categorize them on merits of their purchase decisions

Look, I said I want you to purchase this lens! That being said, my categorizations are mine to make and express. I reserve the right to change them, add to them, and put you into any one of them as I see fit. I suppose I could add "the irrational amateur", who lusts after a lens for reasons he knows are not quite rational. This is a category I might belong to. I think maybe a few, but not many "irrational amateurs" will lust after these very large, very expensive D-FA* - more likely are, at least in my case, lenses like the A 50mm F/1.2 and the FA 77mm Limited. There might also be the "status symbol fetishists", who want everyone to see theirs is the biggest and most expensive toy... Anyway, I don't know why you feel such a strong need to get my moral approval for your lens purchases, so I'll leave it at that.

[awscreo]

Seeing as you are referencing dxo in other posts, and the term "test chart jockey" generated such an epidermic reaction - even going so far as your freudian slip into test chart junkie, I'm not too inclined to think my categorization is off the mark. BTW, to me, a "pro" is someone who doesn't just go off test charts or reviews, but, in his or her areas of core expertise, is good enough (and confident enough) to make up their own mind based on personal, real-world experience. Test charts and reviews can help, but never substitute for a pro's own judgment. So a real pro can't be a review snob - unless he/she wrote the review. All this is IMHO, of course.

Look, I said I want you to purchase this lens! That being said, my categorizations are mine to make and express. I reserve the right to change them, add to them, and put you into any one of them as I see fit. I suppose I could add "the irrational amateur", who lusts after a lens for reasons he knows are not quite rational. This is a category I might belong to. I think maybe a few, but not many "irrational amateurs" will lust after these very large, very expensive D-FA* - more likely are, at least in my case, lenses like the A 50mm F/1.2 and the FA 77mm Limited. There might also be the "status symbol fetishists", who want everyone to see theirs is the biggest and most expensive toy... Anyway, I don't know why you feel such a strong need to get my moral approval for your lens purchases, so I'll leave it at that.

OK got it, looking up reviews, charts and test before purchasing a 1000$+ piece of glass makes one a chart junkie) I guess you just walk into the shop, close your eyes, feel which one gives you a good vibe and buy it like a truly irrational amateur

You certainly can generalize people and create your categories as you see fit, I guess it's Internet and this is nothing new.

[Nicolas06]

Is it not possible to just take dxo's pure numbers and ignore their opinion? They also measure other things, just like any other review website - vignetting, CA, distortion, light transmission etc, but they have a massive database and an easy web interface to compare lenses, which makes them a good starting point to research a new lens. Granted, they mainly concentrate on canikon, and naturally pentaxforum has more overall reviews (although a lot of them are user reviews, so not really scientific) for Pentax related gear.

In any rate, I don't know you personally, and I tend to take online opinions with a grain of salt (as I'm sure most of the people do). I'm not denying 77s qualities, I do not posses the lens myself. I'm merely expressing skepticism that it out resolves the k-1s sensor, as far as I'm aware only few lenses managed to get to that point - Zeiss Otis and Sigma Art 85, both very recent, highly corrected, quite expensive (in Zeiss case very expensive) modern lenses. If 77s is secretly on the same sharpness level, then I will definitely look at buying one ASAP.

What outresolve is supposed to mean? My FA77 closed down is really pixel sharp in the center on the K3 and the FF has less pixel density. All people compared FF and APSC for their wildlife need discover quite fast that FF is not that great for reach and magnification. Already wide open I don't see any lack of sharpness on a full screen, just a lack of contrast. I need to do 100% crop nit picking to see that it is somewhat soft and need f/2.5-f/2.8 to become extremely sharp.

Most lenses outresolve DSLR sensor, bet it APSC or FF, at least closed down in the center. But I mean a 40 year old 50mm prime would do it just as well.

Yet almost no prime, including the latest greatest and expensive from any brand actually outresolve the sensor on extreme corners at f/1.4 or f/1.2. But outside of few specific use cases, this performance isn't even relevant in the filed.

And honestly as 8MP is more than enough for most uses on the final image, having more is for special use cases and having some margin for cropping/PP..

The way the lens render overall, it's color cast, it out of focus / in focus transitions etc on contrary are vislbe even on a 4x6" print or full screen on the computer.

Concentrating on getting more sharpness, in particular when you have lenses like the FA77 is a waste of time.

[Doundounba]

OK got it, looking up reviews, charts and test before purchasing a 1000$+ piece of glass makes one a chart junkie) I guess you just walk into the shop, close your eyes, feel which one gives you a good vibe and buy it like a truly irrational amateur

You certainly can generalize people and create your categories as you see fit, I guess it's Internet and this is nothing new.

I was trying to be whimsical - I actually own neither an FA77 nor an A 50mm F/1.2. I do read reviews, but I never blindly trust them. I am also realistic enough to admit that I lust after a lens like an FA77 for reasons that are not directly related to actually improving my photography. That happens by improving skill rather than getting a lens that performs better on anyone's test chart. I ignored your puerile insult about "ego" a few posts up hoping a rational conversation might actually ensue. But you seem to be determined to get on my bad side, so I'll tell you which category you are now going in - and it's not even my own! It's called: "Ignore".

[awscreo]

What outresolve is supposed to mean? My FA77 closed down is really pixel sharp in the center on the K3 and the FF has less pixel density. All people compared FF and APSC for their wildlife need discover quite fast that FF is not that great for reach and magnification. Already wide open I don't see any lack of sharpness on a full screen, just a lack of contrast. I need to do 100% crop nit picking to see that it is somewhat soft and need f/2.5-f/2.8 to become extremely sharp.

Most lenses outresolve DSLR sensor, bet it APSC or FF, at least closed down in the center. But I mean a 40 year old 50mm prime would do it just as well.

Yet almost no prime, including the latest greatest and expensive from any brand actually outresolve the sensor on extreme corners at f/1.4 or f/1.2. But outside of few specific use cases, this performance isn't even relevant in the filed.

And honestly as 8MP is more than enough for most uses on the final image, having more is for special use cases and having some margin for cropping/PP..

The way the lens render overall, it's color cast, it out of focus / in focus transitions etc on contrary are vislbe even on a 4x6" print or full screen on the computer.

Concentrating on getting more sharpness, in particular when you have lenses like the FA77 is a waste of time.

I thought it means that lens can resolve dark/light lines down to a pixel at extreme magnification. If it can't, then it cannot, then sensor out resolves the lens. With the lenses I have (can see in my sig) I find the newer DFA to be the sharpest out of them all (at certain focal lengths). Yet I can see that it's not the sharpest lens I've personally used, even though it's the sharpest out of the ones I own. The amount of fine detail Nikkor 105 micro can resolve was mind boggling to me, and that set my standard on what I personally consider to be sharp.

If you really want to educate me on the topic, show me some of the method, samples of test images where you can clearly see that older lenses are on the same level as the newer. I'll be more than happy to learn that my old beliefs might not be correct, learning is better than staying ignorant)

---------- Post added 02-23-17 at 01:55 PM ----------

I was trying to be whimsical - I actually own neither an FA77 nor an A 50mm F/1.2. I do read reviews, but I never blindly trust them. I am also realistic enough to admit that I lust after a lens like an FA77 for reasons that are not directly related to actually improving my photography. That happens by improving skill rather than getting a lens that performs better on anyone's test chart. I ignored your puerile insult about "ego" a few posts up hoping a rational conversation might actually ensue. But you seem to be determined to get on my bad side, so I'll tell you which category you are now going in - and it's not even my own! It's called: "Ignore".

Lol that's rich) enjoy your safe space friend!

[D1N0]

Some Pics from cp+ (via Pentaxrumors: More pictures of the new Pentax D FA 50mm f/1.4 lens | Pentax Rumors )

[monochrome]

Small note - square petal hood . . .

[biz-engineer]

But on FF no reasonably sized lens was released yet except 28-105.

The reality is that you don't get a small camera out of a K1, even if it is smaller than competition, it is not pocket-able. Mirrorless has shifted size/performance tradeoffs. When Pentax release the limited lenses, they were competitive on apsc body for their small size because there was no equivalent. When Fuji developed their mirrorless market, mirrorless apsc + prime had an edge over the pentax limited solution (i you consider size). Today, if you want a pocket-able high IQ camera (for travelling or casual photo), mirrorless is best positioned. And if you want the best IQ, durability, and long lenses, you take a FF DSLR body, not pocket-able anymore even with a pancake lens. My experience with the DFA28-105: good sharpness, very small (even small then a 17-70 f4) but unbalanced with the K1. The DFA24-70 balances better with the K1. I understand that Ricoh are releasing large glass for the K1. For small size , there is still the DA ltd on apsc.

[D1N0]

The reality is that you don't get a small camera out of a K1, even if it is smaller than competition, it is not pocket-able. Mirrorless has shifted size/performance tradeoffs. When Pentax release the limited lenses, they were competitive on apsc body for their small size because there was no equivalent. When Fuji developed their mirrorless market, mirrorless apsc + prime had an edge over the pentax limited solution (i you consider size). Today, if you want a pocket-able high IQ camera (for travelling or casual photo), mirrorless is best positioned. And if you want the best IQ, durability, and long lenses, you take a FF DSLR body, not pocket-able anymore even with a pancake lens. My experience with the DFA28-105: good sharpness, very small (even small then a 17-70 f4) but unbalanced with the K1. The DFA24-70 balances better with the K1. I understand that Ricoh are releasing large glass for the K1. For small size , there is still the DA ltd on apsc.

No ILC is pocketable with anything but a pancake lens sticking on it. The Ricoh GR, Now that is pocketable. Small lenses on full frame are very well possible, just look at legacy glass. The K-1 is smaller than some Nikon and Canon APS-C camera's. Just because it is not pocketable doesn't mean you should only use it with big hunks of large aperture glass that resolve pixel perfect from corner to corner.

[Nicolas06]

I thought it means that lens can resolve dark/light lines down to a pixel at extreme magnification. If it can't, then it cannot, then sensor out resolves the lens.

if a new sensor with more pixel density increase the visible resolution, then it mean the previous sensor was not able to fully leverage the resolution of the lens.

Another way to see it; using a TC or pixel shift, you get more details.

As for your definition... Simple example. I tried to find something that would match, but that too boring. I could find some hair in a wedding photo in the end. Taken at f/2.8 that isn't the lens best as per reviews. In attachment full image, 100% crop, 400% crop. This is on a K3 a 24MP APSC that provide more pixel density than K1. K1 cropped to APSC only provide 15MP.

The problem you could have mostly is that the dof is razor thin and almost nothing benefit of the high resolution, but the lens is indeed capable and we see 1 pixel large hair on the photo. Mission accomplished.

Beside let's not forget this is FA lens design for film, not even digital and that the lens is also small and light and a bit further from the registration of the mount than a 50mm would be.

The actual question is how usefull it is? The 100% crop here is 1024. On my 22" monitor, full HD it take 1/4 of the screen. To keep the same magnification on the whole image, I need a 65" 6K TV that doesn't exit yet. And if I am seeing it from further distance than 20", I'll not be able to see more details that what is displayed anyway.

The problme if I do that, if that only the hair are perfectly in focus, and all the rest is OOF. I'd need to use f/8, and there I'd loose the bokeh. This sharpness thing is completely irrelevant. Maybe if I print 40x60" landscape and look at it from near distance I can benefit of the 24MP K3...

[Mistral75]

Some Pics from cp+ (via Pentaxrumors: More pictures of the new Pentax D FA 50mm f/1.4 lens | Pentax Rumors )

Black tape on the golden ring, as if there were some (new?) acronym not to be disclosed too early.

[biz-engineer]

This sharpness thing is completely irrelevant.

On pixel peeping yes. Sharpness is evaluated by zooming in 100%, true. Global image rendering, in this example, depends on the difference between the zones in focus and out of focus areas. Definitely, a fast sharp prime lens renders the final image with the small difference, that differentiate the average shot from the shot that creates a Wow effect. For example, take one of these chinese made fast lenses, even if the sharpness is not that important, you can't get both smooth background and sharp subject (wide open), not because of the thin DoF but because even the center isn't sharp/contrasty wide open. Take a DFA70-200 at f2.8, it is sharpness than the cheapo manual prime and render better. What's the point of using a prime if you have to stop down to f4 ? Ok, the prime is much smaller; that's it.

[Sandy Hancock]

Only thing which does not work with 55mm and K-1 is the APS-C tuned lens hood.

The standard hood has not been a problem on the K-1 in my experience.