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02-13-2016, 09:55 AM   #91
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hey ron, you don't see me promoting sony zooms, so "worship" is not an accurate generalization... i still don't own any fe-mount lenses.

i think that sony is indeed using new technology, no af focus motor for example, so that claim was true.

02-13-2016, 12:37 PM   #92
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QuoteOriginally posted by Rondec Quote
They are nice lenses. OSV and Silver Surfer seem to take their worship of Sony a little far. Silver Surfer said "These lenses use ground breaking technology." And that maybe some day other brands (like Pentax) would use similar tech to try to catch up with Sony.
Why not? Pentax uses Sony Tech already. Sony has a manufacturing process that can produce lenses with Baseline 50 LinePairs/mm resolving power, thats higher than Canon Ziess and Nikon lenses. Why wouldn't you want that tech in a Pentax?

Last edited by Sliver-Surfer; 02-14-2016 at 08:09 PM.
02-13-2016, 01:45 PM - 2 Likes   #93
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QuoteOriginally posted by Sliver-Surfer Quote
Why not? Pentax uses Sony Tech already. Sony has a manufacturing process that can produce lenses with 50 Lines/mm resolving power, thats higher than Canon Ziess and Nikon lenses. Why wouldn't you want that tech in a Pentax?
Because I don't think real world results are going to be that different. And in point of fact, some of my favorite lenses like the FA 31 and FA 77 use quite old tech that renders images in a very natural way. And that is more important to me than sharpness.

But I probably should bow out of this thread. As has been mentioned, I am not particularly interested in Sony's bodies or glass and there is no particular reason for me to be doubting on the Sony tech machine.
02-13-2016, 04:01 PM   #94
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QuoteOriginally posted by Rondec Quote
Because I don't think real world results are going to be that different. And in point of fact, some of my favorite lenses like the FA 31 and FA 77 use quite old tech that renders images in a very natural way. And that is more important to me than sharpness.

But I probably should bow out of this thread. As has been mentioned, I am not particularly interested in Sony's bodies or glass and there is no particular reason for me to be doubting on the Sony tech machine.
Not just sharpness. If anyone want to know more about these lenses read the news link i posted.

02-13-2016, 10:49 PM - 1 Like   #95
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QuoteOriginally posted by Sliver-Surfer Quote
Sony has a manufacturing process that can produce lenses with 50 Lines/mm resolving power, thats higher than Canon Ziess and Nikon lenses.
You can hold it right there, you're out of your depth Silver. This is my area of expertise, and you are wrong. 50 l/mm - even a basic 50mm f/1.4 Takumar from the 60s can accomplish this and on average, current lenses from all major manufacturers frequently pass it, even ultra-fast 50mm lenses can approach it at their widest apertures*. Most high quality lenses can comfortably resolve detail at 100 l/mm and beyond, some of which are made by Olympus,Pentax, Zeiss,Leica,Minolta Canon,Nikon,Schneider,Rodenstock. If 50 l/mm is the best Sony can do, then all I can say is that their lens designers suck.

I harbor no love for Sony, but to say they are the greatest lens manufacturer in the world is absolutely laughable. There is no magical manufacturing process that guarantees perfect lens performance from each and every copy, which if you paid any attention to the sample variations being reported among Sony E mount lenses** which clearly not the case - if there was Carl Zeiss would have an air-tight patent on it.


* 50l/mm = 25lp/mm even the SMCP-K 50mm f/1.2 at the extreme borders scores 22lp/mm(44l/mm) @ f/1.2, the Canon 50L f/1.2 extreme border 23lp/mm (46l/mm) @ f/1.2 Note: these figures are an average for meridional and sagittal resolution @ MTF 50%
** the degree of variation is horrendous especially for wide angle lenses. Also the degree of adjustability on Sony lenses is less than what is visible on the teardowns of Canon and Nikon lenses. So if you get an optically misaligned Sony lens you're better off replacing the entire lens, rather than being able to service the lens and correcting the offending lens element- which means service turnarounds are faster.

Last edited by Digitalis; 02-14-2016 at 12:18 AM.
02-14-2016, 05:57 AM - 1 Like   #96
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QuoteOriginally posted by petrakka Quote
Here's the thing - IQ may not be THE argument to get the Sony.

But the fact that I can easily fit my Sony in my messenger laptop bag and just have it with me basically everywhere I go and have that IQ that is at least equal to all of the other small format cameras, that's where the game changer thing comes in.
This and the universal lens mount via adapters is the killer point for me. Im ashamed to admit that I haven't touched my K30 since buying my A6000, not even turned it on once, it is on the shelf still loved but unused

On the plus side, Im taking more photo's than ever, the redeeming bit being that the EVF has brought all my old manual Pentax glass back to life, I have completely fallen in love with my K30mm F2.8 and my Revuenon 55mm F1.2 is ridiculously easy to focus at F1.2. When I go out now, these are my goto lenses that I always take with me.

I still prefer the ergonomics of my K30, but (for me) manual glass was always a pain on the Pentax, on my Sony it just feels intuitive, even if it slows the process down slightly.

Strangely the whole FF announcement has passed me by, I looked when it was announced, saw no EVF and lost interest, Im addicted to the manual focussing aids that the EVF gives me for old glass, Im lusting after an A7II or A7R II as the better EVF and stabilisation are all I want now.

In the meantime I will keep an eye out for old K Mount glass as I still love the look that Pentax glass has, there is something special about it that I can't put into words. I can't see me buying another Pentax camera unless they do an EVF, but any camera I do buy will be bought for the purpose of shooting with K mount glass so I still see myself as a Pentaxian and Im still a Pentax fan
02-14-2016, 08:13 AM   #97
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QuoteOriginally posted by Digitalis Quote
If 50 l/mm is the best Sony can do, then all I can say is that their lens designers suck.
Sony is designing for 50lp/mm not 50l/mm. Its a typo.

---------- Post added 02-14-16 at 09:18 AM ----------

QuoteOriginally posted by edgedemon Quote
Strangely the whole FF announcement has passed me by, I looked when it was announced, saw no EVF and lost interest, Im addicted to the manual focussing aids that the EVF gives me for old glass, Im lusting after an A7II or A7R II as the better EVF and stabilisation are all I want now.
Once you get use to the EVF it's great to work with. I prefer it to the OVF of the K-3. Its still not as good as a FF OVF, but it doesn't get in the way. I hope to see faster higher resolution EVFs in the near future.

02-14-2016, 02:58 PM   #98
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QuoteOriginally posted by Winder Quote
Sony is designing for 50lp/mm not 50l/mm. Its a typo.
well that is just unambitious, everyone else has broken that barrier.
02-14-2016, 08:08 PM   #99
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QuoteOriginally posted by Winder Quote
Sony is designing for 50lp/mm not 50l/mm. Its a typo.
sorry just saw my typo fixed it oops. 50lp/mm baseline wide open

Last edited by Sliver-Surfer; 02-14-2016 at 08:14 PM.
02-14-2016, 10:18 PM   #100
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QuoteOriginally posted by Sliver-Surfer Quote
50lp/mm baseline wide open
I'll believe that when I see it.

Perhaps at MTF=12% contrast, but at MTF=50%: not a chance, greater lensmakers than SONY have tried. At MTF= 20% contrast Zeiss OTUS 55mm f/1.4 ASPH can reach well over 90lp/mm @ f/1.4* - but at the edges of the 35mm frame Astigmatism becomes problematic reducing contrast by a slight, but distinctly measurable degree. Considering the cost of the OTUS and the amount of QA and QC and R&D that went into its development: SONY doesn't stand a chance.

It makes me wonder what kind of prices SONY are asking for these lenses, and the lenses would have to be twice their current size and weight to accomplish this degree of optical correction and resolution across the 35mm frame at widest aperture. And at which point you would stand more to gain my switching to Medium format, which already has 100Mp sensors on the market, and even then are generally less demanding on optical quality, but the quality of the system are extremely good in any case.

The figure of 50lp/mm is like the old hyperbolic claim from Zeiss of one of their lenses achieving 500lp/mm @ f/5.6 - they never mentioned the contrast percentage at which this result was measured. I suspect would have been somewhere near the Raleigh limit of MTF=9%. I expect SONY Marketing to distort their figures, and hide behind a hogwash caveat like *only under SONY testing* where they can move the goal posts (MTF contrast) to wherever they want.

*which is remarkable for an aperture of f/1.4.

Last edited by Digitalis; 02-14-2016 at 11:00 PM.
02-15-2016, 03:21 PM   #101
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looking at this situation as an lp/mm argument is probably not the right way to do it... when using imatest, dpr and lensrentals for example(??) are using lp/ph, because it compares different sensor sizes better.

"Cropped vs. Full Frame Sensors. One needs to be extra careful when comparing MTF charts amongst cameras with different sensor sizes. For example, an MTF curve at 30 LP/mm on a full frame camera is not equivalent to a different 30 LP/mm MTF curve on a 1.6X cropped sensor. The cropped sensor would instead need to show a curve at 48 LP/mm for a fair comparison, because the cropped sensor gets enlarged more when being made into the same size print.

The diversity of sensor sizes is why some have started listing the line frequency in terms of the picture or image height (LP/PH or LP/IH), as opposed to using an absolute unit like a millimeter. A line frequency of 1000 LP/PH, for example, has the same appearance at a given print size regardless of the size of the camera's sensor. One would suspect that part of the reason manufacturers keep showing MTF charts at 10 and 30 LP/mm for DX, EF-S and other cropped sensor lenses is because this makes their MTF charts look better." Camera Lens Quality: MTF, Resolution & Contrast

wrt zeiss... sort these lists by sharpness:

zeiss owns three out of the top five sharpest lens spots on dxo: Camera Lens Database - DxOMark

but on a sony a7r, the fe90 is sharper than all of the zeiss lenses: Camera Lens Database - DxOMark

so the problem with sony isn't that they can't make sharp glass, but rather, can they get the quality control issues with some of their lenses straightened out.

if they can't, well, so what? just put ef-mount glass on your sony camera.
02-15-2016, 03:40 PM   #102
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Does anyone really sweat those numbers that much in real life?

The Sony and Zeiss lenses make super nice images that have desirable falloff and bokeh and do so on small, light and very capable camera bodies. Meanwhile, I can tell pretty easily that some of my Pentax 645 glass isn't exactly the best stuff on earth but I still like the way it looks on my 645D and a well shot image using any of them would be totally fine for any of my clients or things that I wanted to print really big and put on a wall.
02-15-2016, 06:46 PM   #103
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QuoteOriginally posted by petrakka Quote
Does anyone really sweat those numbers that much in real life?

The Sony and Zeiss lenses make super nice images that have desirable falloff and bokeh and do so on small, light and very capable camera bodies. Meanwhile, I can tell pretty easily that some of my Pentax 645 glass isn't exactly the best stuff on earth but I still like the way it looks on my 645D and a well shot image using any of them would be totally fine for any of my clients or things that I wanted to print really big and put on a wall.
I don't worry too much about the numbers. Yes, I will read them before buying a lens, but image samples are more important. The FE 55mm F/1.8 could score a 0 on the DxO test and I would still love the look of that lens.

---------- Post added 02-15-16 at 07:54 PM ----------

Its not the lenses that are my issue with Sony. I want a better body with faster everything. Sony needs to crank up the processing power and battery power. They need to improve the ergonomics and definitely the menu system.
02-15-2016, 06:57 PM   #104
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QuoteOriginally posted by osv Quote
zeiss owns three out of the top five sharpest lens spots on dxo:
To hell with DxO - I have tested multiple copies of lenses they have reviewed on my optics bench, their test scores are way off the mark. I have been able to match the MTF results from Zeiss lenses - hardly surprising since my optics bench is made by Zeiss.

QuoteOriginally posted by osv Quote
but on a sony a7r, the fe90 is sharper than all of the zeiss lenses
Then the camera is doing something to the images that is enhancing contrast. This is a problem with camera based lens testing that is especially prevalent these days with software lens corrections - manufacturers can shuffle data around to make things look better than they really are. This is why optics benches are the way to go - they are impartial to the lens.
02-15-2016, 07:25 PM   #105
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QuoteOriginally posted by Digitalis Quote
Then the camera is doing something to the images that is enhancing contrast.
even with raw files, i don't think that it has any effect on imatest... jpegs also shouldn't be an issue:

"For commercial RAW files, which are proprietary to camera manufacturers (e.g., CR2 for Canon and NEF for Nikon) and contain proprietary metadata that may be packed (m pixels into n bits), Imatest uses dcraw, a freely available program for converting commercial RAW images to useful file formats with minimal processing. Dcraw can apply simple gamma curves (with no additional tonal response curve).
For the output of manufacturers development systems, which is typically pure binary data, 1 or 2 bytes per pixel, Imatest uses Generalized Read Raw, described below." RAW Files | imatest

"The cropped image is linearized, i.e., the pixel levels are adjusted to remove the gamma encoding applied by the camera." Sharpness: What is it and how is it measured? | imatest

---------- Post added 02-15-16 at 06:27 PM ----------

QuoteOriginally posted by Digitalis Quote
To hell with DxO - I have tested multiple copies of lenses they have reviewed on my optics bench, their test scores are way off the mark. I have been able to match the MTF results from Zeiss lenses - hardly surprising since my optics bench is made by Zeiss.
what are you using to adapt e-mount glass to your bench?
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