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02-24-2017, 06:01 AM - 1 Like   #556
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QuoteOriginally posted by kenspo Quote
Stop spreading lies.
You took that seriously?? No lens that was someone else's and rebuilt for sale as a Pentax has done something like that. Good lord. 35 pages of this and the humor has gone completely out.

I think there's a passing resemblance to the 50 Art here but I think there's plenty of evidence that it's not related at all. I want to see reviews of this thing! I am eager to see how it does in the market when it goes on sale! I'll keep using my M 50 1.4 but I know serious photogs (which I'm not) want / need a lens like this.

02-24-2017, 06:05 AM - 2 Likes   #557
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Then maybe write it in a way so people understands its humor.
02-24-2017, 06:26 AM   #558
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QuoteOriginally posted by ffking Quote
the pictures I get out of it are more pure Pentax than those I get out of the 24-70 - I prefer the rendition, not just the sharpness, and in an undefinable way - it just has that Pentax something that the 24-70 lacks (to me).
I agree. The 24-70 is at its roots a Tamron lens, the 70-200 is a Pentax lens, and with all due respect for Tamron, it shows. The 24-70 is an excellent workhorse with few flaws,. what it lacks is hard to measure but is real.

QuoteOriginally posted by awscreo Quote
Is it not possible to just take dxo's pure numbers and ignore their opinion?
To some extend, yes. As long as you understand that they do not have a statistically valid sample. When I write a review, I'm careful to refer to "the tested lens". Any review on the web should be considered as one sample in the statistical analysis (even, wink wink, mine )

QuoteOriginally posted by awscreo Quote
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.
The flaw in this is that their tests are dependent on the sensors, and as such, cannot be cross-referenced as much as they imply.

QuoteOriginally posted by awscreo Quote
pentaxforum has more overall reviews (although a lot of them are user reviews, so not really scientific) for Pentax related gear.
Actually I think a large sample from several users is more statistically relevant than a small sample from an "expert". But the numbers are less useful than the comments.

QuoteOriginally posted by awscreo Quote
I tend to take online opinions with a grain of salt
As you should.

QuoteOriginally posted by awscreo Quote
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.
I don't have experience with those lenses. But as Nicolas06 writes below, it's a wrong assumption that the K-1's sensor has better resolvng power. Its pixels are larger so it can actually see less detail.

QuoteOriginally posted by Nicolas06 Quote
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.
Well put.

QuoteOriginally posted by Nicolas06 Quote
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.
Yep.

QuoteOriginally posted by Nicolas06 Quote
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 completely agree with this.

QuoteOriginally posted by D1N0 Quote
Some Pics from cp+
That thing is large! I'm surprised at the "DFA*" gold label on the side. The 70-200's label (as well as every other lens in the past) is different. I like consistency in design.

QuoteOriginally posted by Nicolas06 Quote
The actual question is how usefull it is?
Resolution is useful for cropping.
02-24-2017, 06:36 AM - 2 Likes   #559
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QuoteOriginally posted by kenspo Quote
Then maybe write it in a way so people understands its humor.
To this native English speaker it was pretty obviously a joke.
Just smile quietly to yourself, Ken. No need to get defensive

02-24-2017, 06:51 AM   #560
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QuoteOriginally posted by bdery Quote
I agree. The 24-70 is at its roots a Tamron lens, the 70-200 is a Pentax lens, and with all due respect for Tamron, it shows. The 24-70 is an excellent workhorse with few flaws,. what it lacks is hard to measure but is real.



To some extend, yes. As long as you understand that they do not have a statistically valid sample. When I write a review, I'm careful to refer to "the tested lens". Any review on the web should be considered as one sample in the statistical analysis (even, wink wink, mine )



The flaw in this is that their tests are dependent on the sensors, and as such, cannot be cross-referenced as much as they imply.



Actually I think a large sample from several users is more statistically relevant than a small sample from an "expert". But the numbers are less useful than the comments.



As you should.



I don't have experience with those lenses. But as Nicolas06 writes below, it's a wrong assumption that the K-1's sensor has better resolvng power. Its pixels are larger so it can actually see less detail.



Well put.



Yep.



I completely agree with this.



That thing is large! I'm surprised at the "DFA*" gold label on the side. The 70-200's label (as well as every other lens in the past) is different. I like consistency in design.



Resolution is useful for cropping.
I wasn't able to find K-1 + 77ltd samples (would appreciate if someone shares theirs), but I found these full res images with Otus + d810 (should be close enough to k-1's output).
Look at this particular one wide open. Download full res image from flickr. The amount of detail on the man's face is incredible. If 77ltd is indeed on the same level, I'll get one soon)

Zeiss_85f1-4Otus_f1-4_99609 | Zeiss 85/1.4 Otus shot on a D8? | Flickr

I'm not sure how FF vs APSC resolving power compares, probably need some research. I guess if ff sensor is twice the area of the apsc body it should have double the amount of mp to have the same resolving power?

Although my K-1 definitely resolves more detail than my MFT EM-1 which has 4 times smaller sensor area, but not 4 times less resolution.
02-24-2017, 07:03 AM - 2 Likes   #561
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I am exhausted reading this thread.
02-24-2017, 08:04 AM   #562
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QuoteOriginally posted by awscreo Quote
I wasn't able to find K-1 + 77ltd samples (would appreciate if someone shares theirs), but I found these full res images with Otus + d810 (should be close enough to k-1's output).
Look at this particular one wide open. Download full res image from flickr. The amount of detail on the man's face is incredible. If 77ltd is indeed on the same level, I'll get one soon)

Zeiss_85f1-4Otus_f1-4_99609 | Zeiss 85/1.4 Otus shot on a D8? | Flickr

I'm not sure how FF vs APSC resolving power compares, probably need some research. I guess if ff sensor is twice the area of the apsc body it should have double the amount of mp to have the same resolving power?

Although my K-1 definitely resolves more detail than my MFT EM-1 which has 4 times smaller sensor area, but not 4 times less resolution.
It depends on who you are and how you want to measure resolving power:

1) LPM (line-pairs-per-mm) is a microscopic image-plane unit of measurement of resolution that is strongly affected by pixel size but mostly independent of pixel count. With LPM, the FF sensor would need to have double the number of megapixels of the APS-C sensor to resolve the same LPM. (And if one adds in the practicalities of lens design for the larger format, the FF sensor would probably need even more megapixels to match the resolution of the APS-C sensor unless we restrict the resolution measurement to the center of the image.)

2) LP/PH (line-pair-per-picture height) is macroscopic image-plane unit of measurement of resolution that is mostly independent of pixel size but strongly affected by pixel count. With LP/PH, an FF sensor matches the resolving power of APS-C if it has the same number of pixels.

For photographers looking to count the number of hairs on the model's eyebrows or the number of petals in a field of wildflowers, the second measure of resolving power makes more sense. For lens designers developing a lens that might go on APS-C or FF cameras of different resolutions, the first measure makes more sense.
02-24-2017, 08:52 AM - 2 Likes   #563
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f1.4 is really tough with a full frame sensor. Typically you aren't going to see "across the frame sharpness" just because half the image is going to be at least mildly out of focus. Probably most useful for astro photography, maybe some night events.

A few pages back, folks were talking about the DA *55. This is fairly typical performance I see at f2 on the K-1 (full size on Flickr).



It is OK, a little soft in the corners although it was focused at infinity so the lower corners may not be totally in focus. Anyway, it is good enough for my purposes, but certainly there will be those who need something more.

02-24-2017, 09:10 AM   #564
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QuoteOriginally posted by Kunzite Quote
For Pete's sake, people, please stop perpetuating this lie!

---------- Post added 24-02-17 at 10:34 AM ----------


It looks nothing like the D FA*. No element looks similar to the D FA*'s. The shape is different, the size appears to be different (77 vs 72mm filter threads, by the way), everything is different.
Go and compare the Tamron 24-70 (or 15-30) with the corresponding Pentax D FA - there the resemblance is obvious. Even the buttons are the same and not the ones used by Pentax.

No need to reinvent the wheel... let's keep it as in 1968? (when the FA 50 f/1.4's optical design originates).

L.E. My bad, folks - I had another look and now I see how it resembles the Sigma; definite proof of a rebadge! You see, both lenses have the lens mount, distance scale, focus ring and hood in this specific order!
I am not trying to hurt anybodies feelings or am implying some how it is a bad thing because the new Pentax 50mm 1.4 lenses is in a similar vein as the Sigma Art lens. I am not saying Pentax has copied or rebadged the Sigma. All I pointed out is the two lenses are similar which they are. Thanks to Kooks for posting the side by side comparison of the lenses as It is pretty clear from the images that both these lenses are large 50mm lenses along the same line.

The Pentax D-FA* designation intends this lens to be for Pro use. Which puts it in a specialized category and a targeted market. The Sigma weighs over 800g which gives a relative target weight for the Pentax D-FA* 50mm. Personally I am not looking for a lens that weighs as much or more than the camera I am using. Especially if it is a 50mm lens.

The FA 50 weighs under 200g. I prefer this old optical design that keeps the lens as small as possible. What I have hoped Pentax would do is revamp the FA 50 and FA 35 the FA 31/43/77 LTD with modern coatings Quick shift WR etc. Keep something like the Aperture ring. This seems like a no brainer to me for Pentax/Ricoh to undertake. They should do the same with the DA LTD's making them WR. Then they can retire the older designs.
02-24-2017, 09:14 AM   #565
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QuoteOriginally posted by bdery Quote
Resolution is useful for cropping.
I guess the whole thread misses the intend of releasing fat fast sharp lenses for FF. The intention behind this is to eat the cake of medium format, especially with the next generation of full frame sensors. If is already the case with the 5DSr and likely will be more cases of 50+ MP full frame cameras that will compete with MF when using in combination with fast primes. Fuji does the GFX, but take a fast sigma Art on a 5DSr and it cost you less. Obviously, for a lot of hobbyists, those new fast primes my just be luxury items, way beyond what some apsc shooters are happy with.
02-24-2017, 09:16 AM   #566
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QuoteOriginally posted by photoptimist Quote
It depends on who you are and how you want to measure resolving power:

1) LPM (line-pairs-per-mm) is a microscopic image-plane unit of measurement of resolution that is strongly affected by pixel size but mostly independent of pixel count. With LPM, the FF sensor would need to have double the number of megapixels of the APS-C sensor to resolve the same LPM. (And if one adds in the practicalities of lens design for the larger format, the FF sensor would probably need even more megapixels to match the resolution of the APS-C sensor unless we restrict the resolution measurement to the center of the image.)

2) LP/PH (line-pair-per-picture height) is macroscopic image-plane unit of measurement of resolution that is mostly independent of pixel size but strongly affected by pixel count. With LP/PH, an FF sensor matches the resolving power of APS-C if it has the same number of pixels.

For photographers looking to count the number of hairs on the model's eyebrows or the number of petals in a field of wildflowers, the second measure of resolving power makes more sense. For lens designers developing a lens that might go on APS-C or FF cameras of different resolutions, the first measure makes more sense.
Look, i'm just trying to figure out what's the difference between Otus 85 (for example) and the 77 ltd. People here make it seem like they are equal in terms of resolution. I'm trying to see how much truth is in this, so I found a wide open shot with Otus that shows an incredible amount of fine detail on models face. Ok, corner to corner sharpness with a 85mm isn't that important to me, but if I'm buying a portrait lens (not saying I will buy an Otus, unless I win a lottery), I'd like to at least compare available options. You guys can keep looking for the pixie dust and keep thinking all I shoot are charts, I don't really care.
02-24-2017, 09:36 AM   #567
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QuoteOriginally posted by awscreo Quote
I wasn't able to find K-1 + 77ltd samples (would appreciate if someone shares theirs)
Here are a few, shot by yours truly. Be sure to click the images to get full res.

In a studio setting, both at F5.6





Handheld, at F3.5 (the focus point was not perfect in this case, but since we've been splitting hairs :P look at the hair above the head)



another handheld at F3.5. Not a good example for sharpness but good for rendering:



More than the brutal sharpness, however, enjoy (I think) examples of why I think the 77 is a superb lens, sharp or not. The bokeh, the rendering, the out of focus transition, the colours.
02-24-2017, 09:41 AM   #568
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QuoteOriginally posted by Rico Quote
I am not trying to hurt anybodies feelings or am implying some how it is a bad thing because the new Pentax 50mm 1.4 lenses is in a similar vein as the Sigma Art lens. I am not saying Pentax has copied or rebadged the Sigma. All I pointed out is the two lenses are similar which they are. Thanks to Kooks for posting the side by side comparison of the lenses as It is pretty clear from the images that both these lenses are large 50mm lenses along the same line.

The Pentax D-FA* designation intends this lens to be for Pro use. Which puts it in a specialized category and a targeted market. The Sigma weighs over 800g which gives a relative target weight for the Pentax D-FA* 50mm. Personally I am not looking for a lens that weighs as much or more than the camera I am using. Especially if it is a 50mm lens.

The FA 50 weighs under 200g. I prefer this old optical design that keeps the lens as small as possible. What I have hoped Pentax would do is revamp the FA 50 and FA 35 the FA 31/43/77 LTD with modern coatings Quick shift WR etc. Keep something like the Aperture ring. This seems like a no brainer to me for Pentax/Ricoh to undertake. They should do the same with the DA LTD's making them WR. Then they can retire the older designs.
Thank you for the clarification. The first part, I hope you noticed, wasn't in response to your post.

The D FA*50mm f/1.4 (and, presumably, the D FA*85mm f/1.4) follows the trend set by the D FA*70-200 f/2.8: they're "all-out" uncompromising optical designs, large and heavy. I'm amazed at the sight of that monster (albeit I've only seen pictures), however I am not surprised.

What Pentax must avoid is to be seen as the inferior choice. They lost tons of customers because they didn't had FF, or fast AF, or whatever; we should know better than asking them to stay behind their competitors.

By the way, I remember reading in an older interview how if one's re-making the lens barrel in its entirety there's little saving in reusing old optics.
02-24-2017, 09:45 AM   #569
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QuoteOriginally posted by awscreo Quote
Look, i'm just trying to figure out what's the difference between Otus 85 (for example) and the 77 ltd. People here make it seem like they are equal in terms of resolution. I'm trying to see how much truth is in this, so I found a wide open shot with Otus that shows an incredible amount of fine detail on models face. Ok, corner to corner sharpness with a 85mm isn't that important to me, but if I'm buying a portrait lens (not saying I will buy an Otus, unless I win a lottery), I'd like to at least compare available options. You guys can keep looking for the pixie dust and keep thinking all I shoot are charts, I don't really care.
There's so much more to a lens than comparing line pairs or brick wall charts. A better comparison would be two well trained, experienced photographers walking together through a few different areas shooting pictures. One with a K-1 and a 77 Ltd, the other with an 85 Otus and, I don't know, some camera that you can mount that on that compares to the Otus. Come back with their resultant shots and compare.

It would be an interesting test. It would also be a little silly since you can't buy an Otus that mounts to a Pentax, and vice versa with the 77 Ltd. So a thought exersize and maybe a way to compare a classic Pentax lens with a modern Zeiss. What would be more useful perhaps would be this upcoming DFA*85 that is getting talked about now. That would help someone considering a platform change or stepping up to serious pro-level hardware a chance to see what Ricoh's offering the world.
02-24-2017, 09:52 AM - 1 Like   #570
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QuoteOriginally posted by bdery Quote
More than the brutal sharpness, however, enjoy (I think) examples of why I think the 77 is a superb lens, sharp or not. The bokeh, the rendering, the out of focus transition, the colours.
And as has been pointed out countless times, lenses like the 31 and 77 are loved more for their handling of out of focus areas than they are for their sharpness. My Sigma 18-250 could never match my DA*60-250 for bokeh, even shot at the same FL and aperture. That's why we still have the 60-250 and gave the 18-250 to my daughter in law. Digitalis once posted a comparison of the 31 and Sigma 30 1.4. There was a very subtle difference in OoF areas in favour of the 31. That's why the 31 is highly regarded and the 30 1.4, not so much. What many seem to fail to understand is that the differences between average lenses and really good lenses, can be very subtle. If you're looking for a huge difference with lenses made in the last 10-15 years, you probably won't find them. And I guarantee you, if Pentax could do what they did with the 31 and 77 with every lens, they would have. There seems to be an element of luck involved. You're much better off to buy what's really good, than hope something better will come out. The odds are seriously against that, although, it could happen.

Or buy what has the aperture and FL you need and don't worry about pixie dust. There's more than one way to think about lenses.
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