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10-25-2015, 11:17 AM   #106
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QuoteOriginally posted by osv Quote
what you want and what you do doesn't apply to everyone. some people out here need ff, and some people need more options than what pentax offers.
You have a point. I am only saying that many people fail to learn enough about the equipment they already have. They spend money for something to do what they already had the capability to do with the gear they already have. Maybe not as quick or easy. It all about the end result.

---------- Post added 10-25-15 at 02:21 PM ----------

The only need I have for a full frame is that many commercial photography jobs require a full frame as a prerequisite.

10-25-2015, 11:25 AM   #107
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Why? Because there are many loyal Pentax users who want FF! Pentax users were jumping ship. It is better to cover all areas of the industry and Ricoh is finally learning this. Don't worry they'll be working on mirrorless also.
10-25-2015, 11:36 AM   #108
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QuoteOriginally posted by Rondec Quote
I'm happy with my k mount lenses, so that isn't a big deal to me.
we'll see how that shakes out when you start shooting ff k-mount... judging by all the griping that people have been doing, it's not going to be pretty

QuoteOriginally posted by Rondec Quote
As to the Sony thing, it wouldn't be a big deal if it was optional whether or not to apply the lens corrections, but it looks as though it is baked right into the RAW and it is impossible to fully turn off the lens corrections.
i've seen anecdotal evidence of that possibility with maybe two fe-mount lenses; afaik sony has never said any such thing... and there has been no claim of any sony raw corrections in any adapted lens.

if any company were to do that, including the upcoming pentax ff, it would be rather undesirable.

QuoteOriginally posted by Rondec Quote
Finally, it is not unusual to see that level of distortion with a 4x zoom, but these are primes we are talking about.
the thread you mentioned discussed q.c., not lens design, and the L-glass 4%+ distortion is a higher level of distortion than the fe24-70 has:

"As a user you can select whether your images shall be auto-corrected or remain in true RAW mode. In auto-corrected mode, there is, unsurprisingly, nothing to worry about. The distortions stay at less than 0.5% which is negligible. However, the situation changes completely when looking at the original characteristic of the lens. It shows a hefty ~3.8% barrel distortion at 24mm"
Carl-Zeiss Vario-Tessar T* FE 24-70mm f/4 ZA OSS (Sony SEL2470Z) - Review / Test Report - Analysis

that's right, a canon L-glass zoom with more distortion on the wide end than the sony zoom...
10-25-2015, 11:37 AM   #109
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QuoteOriginally posted by osv Quote
that sounds like blind platform fanaticism.
No that is taking photos since 1983 with Pentax. It has always worked for me. It is kind of like a good barber. When you find one that gets your hair just right you use only them.

10-25-2015, 11:45 AM   #110
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QuoteOriginally posted by Tesla Quote
Why? Because there are many loyal Pentax users who want FF! Pentax users were jumping ship. It is better to cover all areas of the industry and Ricoh is finally learning this. Don't worry they'll be working on mirrorless also.
I suspect it is also a reflection of a general move up the market by the whole industry, not least since companies need to protect their revenues or face disaster and, besides, larger-sensor, sophisticated cameras can very clearly do a lot of things a smartphone cannot do and probably never will. It's quite hard to say "good enough" when comparing a smartphone to a 645z or a D810 for most things beyond casual snapping.

This can be seen in the marked increase in average prices over the past few years recorded by CIPA. Fewer units are shipped, but their price is higher and thus revenue holds up better. That's got to be a deliberate policy by all the main players. Ricoh are surely doing the right thing here, i.e. trying to get a chunk of quality revenue from FF rather than rely on revenue from an increasingly rackety APS-C market where bargain basement sharks lurk. It would not be a great surprise if we saw more forays in this area, like an MF from Fuji or even an FF from Panasonic or Olympus. Who knows of course but the momentum to go big on sensor and features and go up market seems to be there.

Last edited by mecrox; 10-25-2015 at 12:05 PM.
10-25-2015, 11:56 AM - 1 Like   #111
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QuoteOriginally posted by macman24054 Quote
No that is taking photos since 1983 with Pentax. It has always worked for me. It is kind of like a good barber. When you find one that gets your hair just right you use only them.
i like wide legacy pentax glass better than other brands that i've tested, i use those lenses on the a7r.

marry the glass, date the body.
10-25-2015, 02:56 PM   #112
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QuoteOriginally posted by osv Quote
we'll see how that shakes out when you start shooting ff k-mount... judging by all the griping that people have been doing, it's not going to be pretty



i've seen anecdotal evidence of that possibility with maybe two fe-mount lenses; afaik sony has never said any such thing... and there has been no claim of any sony raw corrections in any adapted lens.

if any company were to do that, including the upcoming pentax ff, it would be rather undesirable.



the thread you mentioned discussed q.c., not lens design, and the L-glass 4%+ distortion is a higher level of distortion than the fe24-70 has:

"As a user you can select whether your images shall be auto-corrected or remain in true RAW mode. In auto-corrected mode, there is, unsurprisingly, nothing to worry about. The distortions stay at less than 0.5% which is negligible. However, the situation changes completely when looking at the original characteristic of the lens. It shows a hefty ~3.8% barrel distortion at 24mm"
Carl-Zeiss Vario-Tessar T* FE 24-70mm f/4 ZA OSS (Sony SEL2470Z) - Review / Test Report - Analysis

that's right, a canon L-glass zoom with more distortion on the wide end than the sony zoom...
Did you read the link you posted? Roger Cicala says in that link:

"We know that Sony 'cooks the RAW' at least a bit, doing some in-camera modifications to raw files. I don't know exactly what or to what degree. They aren't alone in this, it seems to be the wave of the future to do some in-camera correction for at least distortion. But it appears they are the only full-frame cameras to do in-camera RAW correction at this moment.

What that means, though, is that tests of just the lens without a camera body, like we're doing here, may be quite a bit different than what comes out of the camera. For example, our tests of the FE 35mm f/1.4 ZA show a LOT more distortion than tests done on a camera body using Imatest or DxO optics; we show 4% distortion where most of the on-camera testing shows 1% or less. This probably means that the camera is processing the distortion out of the image. (It could also mean that the distortion is very different focused up close, where DxO and Imatest work, then at infinity, where the optical bench works.) Depending upon your point of view that may be good, bad, or make no difference to you at all."


4 percent distortion on a 35mm prime, even if it is mostly cooked out in the RAW file is a lot. I don't know how important this is, but the FA 31 is measured at 0.8 percent by Klaus on Photozone on a K10 (obviously pre-lens corrections). Considering that the Sony FE 35 f1.4 currently sells for 700 dollars more on Amazon than the FA 31, that seems like a problem.
10-25-2015, 04:11 PM   #113
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QuoteOriginally posted by Rondec Quote
Did you read the link you posted?
think hard about what you just quoted... because he says "This probably means that the camera is processing the distortion out of the image. (It could also mean that the distortion is very different focused up close, where DxO and Imatest work, then at infinity, where the optical bench works.)", and "They aren't alone in this, it seems to be the wave of the future"

it's idle speculation, he's got no real proof that any company is doing any kind of raw distortion correction, and indeed he's claiming that you could be seeing raw correction on the pentax ff camera...

he apparently doesn't even know whether distortion is different at infinity than it is up close for all lenses?? or is it that he just doesn't know if that's the case with the fe35/1.4? overall it sounds like a pretty big gaffe, given that he does imatesting and optical bench testing on all kinds of lenses.

this is reminiscent of his silly claim that adapters lower resolution, when in fact glassless adapters can't alter the internal properties of lenses at all.

QuoteOriginally posted by Rondec Quote
4 percent distortion on a 35mm prime, even if it is mostly cooked out in the RAW file is a lot.
agreed, 4% distortion correction could easily mean a 12% loss in resolution across the entire frame, per roger's testing in the link that i posted earlier...

now sort this list by sharpness, the fe35/1.4 is the 10th highest-rated lens on dxo, on the 36mp a7r, not even the 42mp a7rii Camera Lens Database - DxOMark

it's also tied for first place as the sharpest 35mm prime on dxo, equal to the sigma 35/1.4 on the nikon d800...

does that level of resolution sound like a lens that's been heavily corrected for distortion? those measurements were made on the sony raw file, 0.5% measured distortion.

QuoteOriginally posted by Rondec Quote
I don't know how important this is, but the FA 31 is measured at 0.8 percent by Klaus on Photozone on a K10 (obviously pre-lens corrections).
the fa31 was not tested at infinity, on the lensrentals optical bench, so the 4% optical bench vs. 0.8% imatest chart is apples vs. oranges, it's not comparable.

you want to talk about pentax glass? look at the list, the two highest-resolution lenses on a pentax camera were made by sigma, not pentax...

10-25-2015, 04:21 PM   #114
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QuoteOriginally posted by osv Quote
think hard about what you just quoted... because he says "This probably means that the camera is processing the distortion out of the image. (It could also mean that the distortion is very different focused up close, where DxO and Imatest work, then at infinity, where the optical bench works.)", and "They aren't alone in this, it seems to be the wave of the future"

it's idle speculation, he's got no real proof that any company is doing any kind of raw distortion correction, and indeed he's claiming that you could be seeing raw correction on the pentax ff camera...

he apparently doesn't even know whether distortion is different at infinity than it is up close for all lenses?? or is it that he just doesn't know if that's the case with the fe35/1.4? overall it sounds like a pretty big gaffe, given that he does imatesting and optical bench testing on all kinds of lenses.

this is reminiscent of his silly claim that adapters lower resolution, when in fact glassless adapters can't alter the internal properties of lenses at all.



agreed, 4% distortion correction could easily mean a 12% loss in resolution across the entire frame, per roger's testing in the link that i posted earlier...

now sort this list by sharpness, the fe35/1.4 is the 10th highest-rated lens on dxo, on the 36mp a7r, not even the 42mp a7rii Camera Lens Database - DxOMark

it's also tied for first place as the sharpest 35mm prime on dxo, equal to the sigma 35/1.4 on the nikon d800...

does that level of resolution sound like a lens that's been heavily corrected for distortion? those measurements were made on the sony raw file, 0.5% measured distortion.



the fa31 was not tested at infinity, on the lensrentals optical bench, so the 4% optical bench vs. 0.8% imatest chart is apples vs. oranges, it's not comparable.

you want to talk about pentax glass? look at the list, the two highest-resolution lenses on a pentax camera were made by sigma, not pentax...
I understand that you are a Sony apologist, but if Roger's tests are meaningless, then why post them? If it was just to say that all of the copies of the 35mm that he owns have rough corners, then I guess that is something. I don't understand why distortion would be worse at infinity than close up. That sounds more like a meaningless reason to cover the fact that it exists. If anything distortion is more noticeable close up than at infinity.

Oh well, I am not planning to buy any Sony lenses, so it doesn't matter to me, but certainly if I were, this review and Photozone's analysis would give me pause.
10-25-2015, 05:34 PM   #115
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the biggest take-home for me with roger's testing was that he tested 10 copies of three different lenses, and the results were all over the map for two of the lenses, which speaks volumes about sony q.c.

second point was that roger stated in the comments that the sigma 35/1.4 variance was just as bad as the sony fe35/1.4 variance, which will matter to pentax people if sigma releases it in a ff k-mount.

i don't understand how dxo can rate lenses that have so much variance, and i definitely don't get the extreme differences in distortion measurement, for optical bench vs. imatest, he should have explained that... if he even could.

wrt to your point about the raw files getting distortion correction:
"Despite being a wide-angle lens, the FE 35mm ƒ/1.4 Zeiss lens displays impressive distortion control, on both full- and sub-frame cameras. Like vignetting, Sony cameras can apply in-camera corrections for distortion. We measured both with and without, and it does appear that Sony RAW files are affected with this correction as both tests showed nearly identical results. We found average barrel distortion was well under +0.5% and even the maximum value of distortion -- typically displayed in the corners -- was still under the +0.5% level." Sony Lens: Primes - Sony FE 35mm f/1.4 ZA Zeiss Distagon T* SEL35F14Z (Tested) - SLRgear.com!

are those corrections just numbers in the raw file, being applied by the raw processor, which is how everything else is done in a raw file? or is the image permanently altered.
10-26-2015, 12:04 AM   #116
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QuoteOriginally posted by osv Quote
think hard about what you just quoted... because he says "This probably means that the camera is processing the distortion out of the image. (It could also mean that the distortion is very different focused up close, where DxO and Imatest work, then at infinity, where the optical bench works.)", and "They aren't alone in this, it seems to be the wave of the future"

it's idle speculation, he's got no real proof that any company is doing any kind of raw distortion correction, and indeed he's claiming that you could be seeing raw correction on the pentax ff camera...

he apparently doesn't even know whether distortion is different at infinity than it is up close for all lenses?? or is it that he just doesn't know if that's the case with the fe35/1.4? overall it sounds like a pretty big gaffe, given that he does imatesting and optical bench testing on all kinds of lenses.

this is reminiscent of his silly claim that adapters lower resolution, when in fact glassless adapters can't alter the internal properties of lenses at all.
No there nothing silly here. Classical lense testing with imatest or DxO is a very specific environement. It may reflect well close-up performance and is pretty meaningfull for say portraiture work but it is not that well representation for say landscape and architecture were the actual subject is at the inifinite.

We all know that lenses have different performance at different focussing distance. a typical issue is that a lense doesn't perform as good at extreme settings like foccussed to the infinite at minimum focussing distance.

The distorsion could very well be different at different focus setting as the optical elements are not in the same position. After all the focal length change when you change focussing distance, exactly like a zoom (the amount depend of the design, the 60-250 is know to be more like 135mm max focussed close) and zoom typically have different distorsion characteristics at different focal length.

Sony could very well have optimized the lense for the typical benchmark application. Who would say they would never do that nowadays with the Volkswagen affair on one side and the visible tendancy for lenses manufacturers to concentrate on aspects that review tend to favor (resolution, optical aberations) ? Manufacturers in general now try to do as much in RAW to hide the optical issues of their lenses. That's not new. Part of K5 success is that it perform so well at high iso and ironically Pentax add a some blur to it's raw files starting 3200 isos to hide the noise.

Honestly we know Sony tend to under design many lenses and to correct things through software. I would not be surprised a bit if the 35mm f/1.4 did benefit of this too.

Reality is that if you want to see if a lense match your requirement you should see more photographs taken with it, and avoid to put to much faith in the reviews that concentrate only on a limited set of aspects of the gear.
10-26-2015, 12:10 AM   #117
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QuoteOriginally posted by osv Quote
this is reminiscent of his silly claim that adapters lower resolution, when in fact glassless adapters can't alter the internal properties of lenses at all.
Explain us then what an extension tube does or why you can't simply use any optics on any camera in particular when the registration distance of the actual lense is shorter than the registration distance of the target camera.

Optics are high precision material that need perfect alignement, the smallest change in distance between 2 elements can have huge effect on picture quality. This is why so many lenses are indeed defective or not at their optimal level: the tolerances are tight.
10-26-2015, 12:28 AM   #118
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Based on the features that appear to be included in the new Pentax full frame camera, it is intended for the professional market. If Pentax is to become a major player, it needs a FF flagship. Aps-c cameras are nice, but they don't command the same recognition that FF's do. I added FF to my kit a couple years ago and I use it more then my aps-c camera. Choices are a good thing. I think that this baby will cost at least 3k USD.
10-26-2015, 01:17 AM   #119
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QuoteOriginally posted by Nicolas06 Quote
Sony could very well have optimized the lense for the typical benchmark application.
they would be stupid not to, but the downside to this is that such a lens would have glaring weaknesses outside of that specific scenario, e.g real life photography.

Also, are you misspelling Lens deliberately to give me a headache? because it is working
10-26-2015, 02:21 AM   #120
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QuoteOriginally posted by osv Quote
i don't understand how dxo can rate lenses that have so much variance, and i definitely don't get the extreme differences in distortion measurement, for optical bench vs. imatest, he should have explained that... if he even could.
It's not really news that distortion differs a LOT between very close focus settings and infinitiy focus for many lenses.

Since - at least in my book - photography outside macro scenarios - happens closer to infinity than to very close focussing I consider all imatest (= very close target focus) based distortion "measurements" a silly waste of webspace as they are irrelevant lower-than-amateur nonsense. That does include DxO, dpr and Photozone obviously.

As far as testing and reviewing lenses goes I consider lensrentals the single (semi-)reliable source. They have an optical bench and do test multiple copies in most cases. All the others don't do better testing and reviewing than any user here in his home basement.
Imatest and single copy means nothing if you even want to apply enthusiast amateur standards to reviewing.
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