liquid stereo
Veteran Member
Are there modern primes with apertures of 1.8 or slower that have CA problems? I've not encountered one. Maybe I've been luck.
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Sigma says the E-mount too small for FF.
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Tuloom
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Every lens I've ever owned had some level of CA. The Canon EF 35mm 2.0 had horrible bokeh fringing. The FE35 2.8 is prone to teal green fringing. It's just something you have to deal with (in LR for me). I do consider CA much better as a whole with modern lenses ---except, for example, the Zeiss 35mm 1.4 Distagon--- but saying it's a non-issue is rather broad. Each would have to be taken individually.
Notable examples of two that exhibit nearly none are the Canon FD 80-200 f4L and the CV125 APO f/2.8. But even under the right circumstances both will produce aberrations.
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No, not really. Well, that also depends what part of IQ is considered.
Designing a more conservative aperture (close to that of FE 55) in a small package is not difficult at all. As a matter of fact, Zeiss designers took an extra difficult task on themselves starting from a triplet-based design, hence the size of FE 55. They had to go extrra length to make it sharp using aspheric elements, and still were npot able to correct the longitudinal chromatic aberrations as well as older designs based on different design form. It is not a close-focusing lens either. But the reward for going with Sonnar design was a much nicer bokeh.
Other manufacturers (such as Sigma) can start with a more powerful design form (sharpness and aberration correction wise), the Double Gauss. A prime example of such lens is Contax Zeiss 45/2, a lens ideally sized for A7 series cameras. Please, no nonsence about the size penalty due to autofocus, ring USM motors hardly take any room at all.
Despite being an old lens, it still corrects LoCA better than FE 55, is nearly as sharp in the center and only loses to FE55 in the corners wide open. Reoptimizing this lens for the coverglass thickness should take care of the latter, and aspherizing more elements (well within Sigma reach) would make it even sharper (not taht it needs it as it is, actually). Making a smaller, sharper and better CA corrected lens than mighty FE55 is not a problem (at expense of bokeh quality).
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EinsteinsGhost
Forum Pro
Silly is choosing to ignore what a fast lens entails: not just about transmitting light, but doing so more efficiently.
EinsteinsGhost
Forum Pro
It is fast enough, and a smart decision. In fact, I'm afraid that Sony might have listened to way too many calling f/1.8 "slow" and is reworking its FE 85 to be f/1.4 (and it ain't going to be small: see Samsung's 85/1.4). I would rather see FE 85/1.8, the smart choice for both speed and size.
Your expectations go past the laws of Physics. Sony FE 55 is SIGNIFICANTLY smaller than the other two lenses it compares well optically with: Otus 55/1.4 and Sigma 50/1.4 ART. It is kinda funny when I see people call 840g FE 70-200 "too heavy" but 815g (Sigma) to almost 1000g (Zeiss Otus) 50-55mm lenses get away without the label.
EinsteinsGhost
Forum Pro
You're right... Sigma can only make a lens perform well if they make it oversized.Good performance and small size.That is utter nonsense: put an A-mount adapter on the E-mount, and then mount an A-mount Sigma lens. Now, all of a sudden, it works just fine?
I have yet to see a lens design with an aperture larger than the sensor and so close the the mount blocks the rays - I think that it is physically impossible to design such a lens, and why would you? (I am thinking perhaps a 1,000mm f/1.2 lens
Any normal lens will project outward from its exit pupil, somewhere suspended in front of the sensor. Lens-mount and diameter play no role in this, other than that it dictates that the exit pupil is outside of the camera body, inside the lens somewhere. And, as we have learned, it shouldn't be too close to the sensor - see the problems with WA RF lenses.
Why Sigma would claim such a thing is beyond me. Is he a spokesman for Sigma? Or just misinformed.
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Cheers,
Henry
EinsteinsGhost
Forum Pro
One of your points is a valid one: You've to design a lens to work well. It won't happen automatically. You've to use good optics and engineering. A result: FE 55.
Why is it that Sigma finds itself incompetent there? A 55mm lens with 1.8 aperture (and DXO's measure T1.8) might not satisfy people who blindly chase 1.2 or 1.4, and would not accept anything but a defiance of the laws of Physics, but Sigma could surely design a more compact and better FE 50 even if it is "only" 1.8? Or, may be not.
EinsteinsGhost
Forum Pro
Post a link to it, then we discuss. Until then, this will remain something pulled out of thin air.
of any compromise, WRT the FE primes. So four so far - f1.8/f2.8/f2/f2.
'Despite being an old lens, it still corrects LoCA better than FE 55, is nearly as sharp in the center and only loses to FE55 in the corners wide open.'
It's the first time I have ever encountered this criticism of the 55mm, provide examples? Despite being quite unsuitable for the FEs the G lenses are of course very fine, overall. But the 45/2 is a traditional Planar design of the kind that had people wondering how Sony could ask $1000 for the FE55. Because it is that much better, that is why.
The 45/2 peaks at just f4 according to CZ; the FE55 still improves across the frame at f8, with centre performance just a tiny bit less than f5.6. Corners are exemplary everywhere, even f1.8. This is the dividend of high quality slow lenses - slow lenses are better quality lenses overall. People equate lens speed with quality, even experienced users.
It's understandable, as the better fast lenses produce fabulous photos with excellent bokeh - as seen in many f1.4 Leica M lenses. Don't try to use a Summilux and expect FE55 (or RX1) performance for say, built structures or landscapes, however, the result will be embarrassing.
So the 45/2G is way below at f2, then peaks early, does very well inside the borders for an older design, but corners, well, let's just say there has not been a rush on that Planar since the a7r saw light of day.
ALL the best new 50-55 lenses share the same measured MTF outcome as the FE55 - high flat lines to the very edge! No, not a coincidence, just a final realisation of the needs of lens design in the modern high Mp era. The top four are, in no particular order: FE55, Sigma ART, Otus 55mm and Leica's new 50AA (f2 also, note).
Here is the G45/2 at its best:
Typical Planar fall-off, past 17mm of image height with roller coaster fine detail (bottom lines)
So what happens with such a pattern is a disruption of rendering of fine detail as you move outwards from image centre...the detail lines (40lpmm) go from 72% to almost 80% to break open and separate (midfield curvature likely) then recover at 17mm then fall off the cliff. Your 'planar' subjects in image space look strange when this happens - contrast and 'sharpness' alters the faithfulness of the subject.
The real strength of the FE55 is the near absence of defects, in a small package, very light, AF, no one notices it, and it packs a punch only the exalted few can match, at either a huge weight or a huge cost or both. Sony did us all a solid and raised the bar for what can be done for lenses in the mainstream. Any wonder people have to invent stuff like 'clinical' or 'LoCA'.
The Sigma guy is likely just sore at seeing the future change in front of his eyes, since they hitched their wagon to C/N DSLRs. We still have the 35/1.4D to come in FE, for character lens aficionados.
'Despite being an old lens, it still corrects LoCA better than FE 55, is nearly as sharp in the center and only loses to FE55 in the corners wide open.'
It's the first time I have ever encountered this criticism of the 55mm, provide examples? Despite being quite unsuitable for the FEs the G lenses are of course very fine, overall. But the 45/2 is a traditional Planar design of the kind that had people wondering how Sony could ask $1000 for the FE55. Because it is that much better, that is why.
The 45/2 peaks at just f4 according to CZ; the FE55 still improves across the frame at f8, with centre performance just a tiny bit less than f5.6. Corners are exemplary everywhere, even f1.8. This is the dividend of high quality slow lenses - slow lenses are better quality lenses overall. People equate lens speed with quality, even experienced users.
It's understandable, as the better fast lenses produce fabulous photos with excellent bokeh - as seen in many f1.4 Leica M lenses. Don't try to use a Summilux and expect FE55 (or RX1) performance for say, built structures or landscapes, however, the result will be embarrassing.
So the 45/2G is way below at f2, then peaks early, does very well inside the borders for an older design, but corners, well, let's just say there has not been a rush on that Planar since the a7r saw light of day.
ALL the best new 50-55 lenses share the same measured MTF outcome as the FE55 - high flat lines to the very edge! No, not a coincidence, just a final realisation of the needs of lens design in the modern high Mp era. The top four are, in no particular order: FE55, Sigma ART, Otus 55mm and Leica's new 50AA (f2 also, note).
Here is the G45/2 at its best:
Typical Planar fall-off, past 17mm of image height with roller coaster fine detail (bottom lines)
So what happens with such a pattern is a disruption of rendering of fine detail as you move outwards from image centre...the detail lines (40lpmm) go from 72% to almost 80% to break open and separate (midfield curvature likely) then recover at 17mm then fall off the cliff. Your 'planar' subjects in image space look strange when this happens - contrast and 'sharpness' alters the faithfulness of the subject.
The real strength of the FE55 is the near absence of defects, in a small package, very light, AF, no one notices it, and it packs a punch only the exalted few can match, at either a huge weight or a huge cost or both. Sony did us all a solid and raised the bar for what can be done for lenses in the mainstream. Any wonder people have to invent stuff like 'clinical' or 'LoCA'.
The Sigma guy is likely just sore at seeing the future change in front of his eyes, since they hitched their wagon to C/N DSLRs. We still have the 35/1.4D to come in FE, for character lens aficionados.
Good grief, a LoCA denial-ist?
Both the SEL50F18 (which I have... twice) and SEL55F18Z (as seen and pointed out in shots here) suffer from LoCA more than other 50's I've had, a relevant one being a Contax Zeiss Planar f/1.7. Granted, the SEL designs (which are quite similar, despite some of you wanting to exalt the SEL55F18Z might not want to admit) have their advantages... but seriously, it's not perfect.
On an unrelated note, I don't know why you don't know how to quote posts correctly. I suppose it makes what Krich13 said easier to take out of context?
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Old Ed
Senior Member
...but it seems to be working pretty well. ;-)
captura
Forum Pro
Maybe they don't have enough confidence in the Sony FF market.
captura
Forum Pro
The last part of SAR's post said, "he expects big new PRO cameras to be announced at the CP+ show in Japan (February 2015)."
The meaning of that remark...could be a new medium format camera?
The meaning of that remark...could be a new medium format camera?
captura
Forum Pro
The 30/2.8 and 19/2.8 DN Sigma lenses are identical for both Sony APS-C E-mount and M43, except for the lens mount of course. But little known is that there was also going to be a Samsung version, which never materialized because Samsung introduced their very own NX-30 around that time.
Samsung lenses are longer registry than NEX or M43. Sigma took this into account for their 19 and 30 designs, which explains why these lenses are longer than one would normally expect.
PS and off topic: Somebody, please make an NX to E-mount smart adapter, OK? Those Samsung lenses are as good or better than Sony, for APS-C.
'Other than the enthusiast unfriendly pro lenses, what FF lenses for Canon EOS mount are distinguished by their IQ?'
FIFY. Can also provide the answer: none. Most former adherents tell me the last one they gave up on is the 135/2, itself relegated to the shadows by, among others, the Zeiss ZE 135/2 APO-Sonnar.
And as a second bonus, there are four FE FF lenses, two just out. Would any Canon owner - given the opportunity to choose - prefer the corresponding EF lens to any of them, on the basis of IQ?:
35/2.8; 55/1.8; L50/2 and L35/2.
When we talk from behind the barbed wire fence of mount allegiance, we risk coming over as less knowledgeable of the facts that apply outside the prison compound. Not your fault, and if needed, you can be directed to reviews and MTF charts. It gets easier as you learn more.
Unlike Canon, Sony must compete with the best in the business, due to its open source mount. They do, starting with business partner CZ. Canon however, is the Chevrolet of full frame photography - brute force and ignorance. Times are changing! cheers.
FIFY. Can also provide the answer: none. Most former adherents tell me the last one they gave up on is the 135/2, itself relegated to the shadows by, among others, the Zeiss ZE 135/2 APO-Sonnar.
And as a second bonus, there are four FE FF lenses, two just out. Would any Canon owner - given the opportunity to choose - prefer the corresponding EF lens to any of them, on the basis of IQ?:
35/2.8; 55/1.8; L50/2 and L35/2.
When we talk from behind the barbed wire fence of mount allegiance, we risk coming over as less knowledgeable of the facts that apply outside the prison compound. Not your fault, and if needed, you can be directed to reviews and MTF charts. It gets easier as you learn more.
Unlike Canon, Sony must compete with the best in the business, due to its open source mount. They do, starting with business partner CZ. Canon however, is the Chevrolet of full frame photography - brute force and ignorance. Times are changing! cheers.
First, I don't think that Sony wants top set the world on fire.
Then about the lenses: take a close look at the 35mm F2.8 (not fast but small and opticly very good, and the 70-200mm f4 is very good. both lenses are comarable in quality with equaly speced and or priced lenses from Canon and Nikon.
Not clear on your questions and points. I have a Canon 35mm f2 IS that I use extensively on my Canon 70D and Sony 35mm f1.8 OSS that I use extensively on my Sony a6000. I like my Sony 35mm but after very extensive use with both lenses I can very clearly say my Canon 35mm f2 IS is noticeably sharper and IS is at least one stop better.
In addition, I have a Canon 70-200 f4 IS. Just returned a Sony 70-200 f4 OSS. The difference I found here was even worse. I may have gotten a bad Sony copy and can only compare one lens to one lens. However, of the two 70-200's I had-after 2 weeks of very extensive testing of all kinds related to what I do-I can definitively state the difference was even more in Canon's favor. The Sony 70-200 copy I had was worth no where near the $1500 I paid. Not sure what I will do to find an E-mount 70-200 good enough for my needs.
Not sure what the problem is with Sony e-mount non-Zeiss lenses. I am keeping my Sony 35mm f2 OSS. It is good enough for what I use it for. Not the Sony 70-200 f4 OSS though.
In addition, I have a Canon 70-200 f4 IS. Just returned a Sony 70-200 f4 OSS. The difference I found here was even worse. I may have gotten a bad Sony copy and can only compare one lens to one lens. However, of the two 70-200's I had-after 2 weeks of very extensive testing of all kinds related to what I do-I can definitively state the difference was even more in Canon's favor. The Sony 70-200 copy I had was worth no where near the $1500 I paid. Not sure what I will do to find an E-mount 70-200 good enough for my needs.
Not sure what the problem is with Sony e-mount non-Zeiss lenses. I am keeping my Sony 35mm f2 OSS. It is good enough for what I use it for. Not the Sony 70-200 f4 OSS though.
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