p.18 #1 · Zeiss "Batis" AF lens line to be released for FF E-mount
ecarlino wrote:
they must deliver the newspaper a few days late in Ohio as well......
Bit harsh maybe (I can't claim I fully grasp all the stereotypes from each US state), I hope jsv_20 has a sense of humour, but yes, the Zeiss Batis samples and their sometimes unusual dimensions were discussed several pages back.
I've just got back from the pub and think I've finally grasped the intricacies of distortion correcting transformations but insights will have to wait until the morning...
p.18 #2 · Zeiss "Batis" AF lens line to be released for FF E-mount
bjornthun wrote:
What's the issue with focus-by-wire? I find that it's capable of a better (longer) focus throw than most other lenses. My Touit 32/1.8 gives 3/4 turn = 270 degrees. The Sony/Zeiss FE/E lenses give a long or short throw depending on how fast you turn the focus ring. So for precise MF I find focus-by-wire to be superb.
i'm delayed in response here as i've been away, but i hate focus by wire with a passion because it is terrible for tracking moving subjects (mostly people in my case)! the fact that how fast you turn the ring changes the focus throw makes smooth tracking nearly impossible. my most recent experience with FBW is the sony rx1 and FE 55. i can get roughly 5x as many hits with manual focus lenses of the same focal length on my a7 (c/y 35/1.4 and rokkor 58/1.2 shot at similar apertures) as i can using FBW. for what it's worth, on the a7 i get roughly 20x more keepers using the previously mentioned manual focus lenses to shoot portraits of moving people at large aperture compared to using AF on the rx1 or FE 55 and 3x as many keepers as i get on a 5dIII + 85/1.8 using AF and have more difficulty getting the compositions i want using AF.
p.18 #3 · Zeiss "Batis" AF lens line to be released for FF E-mount
sebboh wrote:
i'm delayed in response here as i've been away, but i hate focus by wire with a passion because it is terrible for tracking moving subjects (mostly people in my case)! the fact that how fast you turn the ring changes the focus throw makes smooth tracking nearly impossible. my most recent experience with FBW is the sony rx1 and FE 55. i can get roughly 5x as many hits with manual focus lenses of the same focal length on my a7 (c/y 35/1.4 and rokkor 58/1.2 shot at similar apertures) as i can using FBW. for what it's worth, on the a7 i get roughly 20x more keepers using the previously mentioned manual focus lenses to shoot portraits of moving people at large aperture compared to using AF on the rx1 or FE 55 and 3x as many keepers as i get on a 5dIII + 85/1.8 using AF and have more difficulty getting the compositions i want using AF.
Hi Derrick. I agree I really don't like the focus by wire with the FE 55/1.8 and FE 35/2.8. The FE 35/1.4 is very different IMO. The dampening and movement has now been optimized to the point where I now freely use AF and MF, particularly when I am shooting close @ f/1.4. I also like the Loxia's too for this reason
p.18 #4 · Zeiss "Batis" AF lens line to be released for FF E-mount
Matt, never realised just how bad the distortion of that 28mm was. Yikes. Looks like my old Canon 16-35LII @ 16mm. I'm rather sure actually that my FE 16-35mm isn't that bad.
p.18 #5 · Zeiss "Batis" AF lens line to be released for FF E-mount
Beni the distortion of the 28 is much less high than most (excellent) M43 lenses; it's just that M43 doesn't allow you to turn off distortion correction in major raw processors.
The 28 has surprisingly high resolution for a relatively inexpensive lens; enough so that that after correction it's still somewhat surprisingly high! And you have the option of not turning on correction.
p.18 #6 · Zeiss "Batis" AF lens line to be released for FF E-mount
Someone said that they have a massive psychological barrier against lenses designed to have their distortion software corrected.
i think I'm developing a psychological barrier against lenses which have their distortion optically corrected!
Here's why: optical distortion correction costs resolution. And if it is optically corrected, that's locked in: you can't get it back! At least if you took the same lens design and didn't optically correct (I know it's hard to compare) you will start of with higher resolution. Of course, after software correction, you lose it again. But there are scenes in which you don't need to correct - and then you can the full goodness of uncorrected resolution.
Of course exactly what the resolution costs of optical correction versus software is unclear. Modern lenses which are well corrected for distortion tend to be expensive too. So it's hard to compare apples with apples. Here's my guess: with low MP sensors, software correction will be worse than with high MP sensors, because the higher the sensor resolution, the more you can forget the limit of sharpness imposed by the sensor resolution, and the more you can think of the image as approximating an analogue representation of the sharpness of the lens.
p.18 #7 · Zeiss "Batis" AF lens line to be released for FF E-mount
DavidBM wrote:
Beni the distortion of the 28 is much less high than most (excellent) M43 lenses; it's just that M43 doesn't allow you to turn off distortion correction in major raw processors.
The 28 has surprisingly high resolution for a relatively inexpensive lens; enough so that that after correction it's still somewhat surprisingly high! And you have the option of not turning on correction.
The 28 has good resolution in the center on a 24Mp sensor, but it gets noticeably worse towards the edges to the corners. It the edges and corners that get most affected by the resolution loss from barrel distortion correction. In the end, the edges and corners are just OK.
p.18 #8 · Zeiss "Batis" AF lens line to be released for FF E-mount
Matt Grum wrote:
If it's aberrations that are really hard to remove, like longitudinal CA (axial colour), then I agree with you there, for a fast portrait lens. In a lens used for architecture resolution would be more important to me, so I'd rather a distortion corrected optic.
All aberrations other than distortion lower the resolution, and are hard to remove. Axial color is a nasty one, but so are spherical aberration, coma, astigmatism, and field curvature. Correction of lateral color is to some extent similar to distortion correction, but more complex.
p.18 #9 · Zeiss "Batis" AF lens line to be released for FF E-mount
DavidBM wrote:
Someone said that they have a massive psychological barrier against lenses designed to have their distortion software corrected.
i think I'm developing a psychological barrier against lenses which have their distortion optically corrected!
Here's why: optical distortion correction costs resolution. And if it is optically corrected, that's locked in: you can't get it back! At least if you took the same lens design and didn't optically correct (I know it's hard to compare) you will start of with higher resolution. Of course, after software correction, you lose it again. But there are scenes in which you don't need to correct - and then you can the full goodness of uncorrected resolution.
Of course exactly what the resolution costs of optical correction versus software is unclear. Modern lenses which are well corrected for distortion tend to be expensive too. So it's hard to compare apples with apples. Here's my guess: with low MP sensors, software correction will be worse than with high MP sensors, because the higher the sensor resolution, the more you can forget the limit of sharpness imposed by the sensor resolution, and the more you can think of the image as approximating an analogue representation of the sharpness of the lens....Show more →
Mabye there should be a new term...Optical Rationalization...
p.18 #10 · Zeiss "Batis" AF lens line to be released for FF E-mount
I did a quick test switching software distortion correction on and off with a recent photo I took with the FE 16-35mm. Shot at 18mm, 135 girls, was a year photo for a school. The resolution difference at the centre is pixel peeping level but it is there albeit slight. What seems most noticeable is the drop in 'bite' in the very fine details, in this case the hair. I'm actually quite impressed at how little correction is needed with this lens, it's the same or less than I'm used to from my Canon 16-35LII. Given the distortion of the FE 24-70 I'd expected worse.
p.18 #11 · Zeiss "Batis" AF lens line to be released for FF E-mount
Tariq Gibran wrote:
Mabye there should be a new term...Optical Rationalization...
Well, I really hate to disagree with some of the most distinguished members of this board, but to me, a high quality lens should be well corrected for all aberrations, physically I consider the need for software correction as a kind of cheating Don't crucify me for saying that, just my opinion.
I do agree however that distortion is much more preferable to lateral CA, an aberration very common with SLR lenses. But since I switched to rangefinders, none of the ZM lenses I have owned or tried has any noticeable lat. CA and distortion is quite low. This proves that with the absence of the mirror design restrictions it is not difficult to make well corrected lenses. I would expect the same quality from the new Batis line, as the quality I get with the ZM line.
p.18 #12 · Zeiss "Batis" AF lens line to be released for FF E-mount
edwardkaraa wrote:
Well, I really hate to disagree with some of the most distinguished members of this board, but to me, a high quality lens should be well corrected for all aberrations, physically I consider the need for software correction as a kind of cheating Don't crucify me for saying that, just my opinion.
I'm in 100% complete agreement with you myself. "Rationalization" is of course a mental trick to justify a negative situation.
p.18 #13 · Zeiss "Batis" AF lens line to be released for FF E-mount
sebboh wrote:
i'm delayed in response here as i've been away, but i hate focus by wire with a passion because it is terrible for tracking moving subjects (mostly people in my case)! the fact that how fast you turn the ring changes the focus throw makes smooth tracking nearly impossible. my most recent experience with FBW is the sony rx1 and FE 55. i can get roughly 5x as many hits with manual focus lenses of the same focal length on my a7 (c/y 35/1.4 and rokkor 58/1.2 shot at similar apertures) as i can using FBW. for what it's worth, on the a7 i get roughly 20x more keepers using the previously mentioned manual focus lenses to shoot portraits of moving people at large aperture compared to using AF on the rx1 or FE 55 and 3x as many keepers as i get on a 5dIII + 85/1.8 using AF and have more difficulty getting the compositions i want using AF.
...Show more →
I understand that. Indeed I have used several manual lenses with exactly the right focus throw, Leica R, Nikon Ai are good. Some MF lenses on the other hand have a too short throw, particularly close to infinity, the Zeiss 100/2 MP is a example of this. Most AF lenses that are not focus by wire have a too short throw in my opinion. So I actually like FBW lenses. The sensitivity to speed of the focus throw allows me to quickly get the lens from near to infinty, so I think it's good. Particularly compared to AF lenses with clutch mechanism, I prefer FBW. Still for a good MF feel I think Leica R and Nikon Ai are among the best, though I prefer FBW lenses, since they give me the option of AF as well. To me they are the best compromise.
p.18 #15 · Zeiss "Batis" AF lens line to be released for FF E-mount
edwardkaraa wrote:
Well, I really hate to disagree with some of the most distinguished members of this board, but to me, a high quality lens should be well corrected for all aberrations, physically I consider the need for software correction as a kind of cheating Don't crucify me for saying that, just my opinion.
I disagree. I think that the total outcome matters, and that the combination of optical and digital correction is the way ahead. An example is lenses that corrects LoCA at the expense of lateral CA optically, and then rely on digital correction of lateral CA. This is much preferable to optically correcting lateral CA, but not correcting LoCA, which is difficult to correct digitally.
p.18 #16 · Zeiss "Batis" AF lens line to be released for FF E-mount
bjornthun wrote:
I disagree. I think that the total outcome matters, and that the combination of optical and digital correction is the way ahead. An example is lenses that corrects LoCA at the expense of lateral CA optically, and then rely on digital correction of lateral CA. This is much preferable to optically correcting lateral CA, but not correcting LoCA, which is difficult to correct digitally.
To my eyes, loCA is the least objectionable aberration and I certainly wouldn't mind it. Notice that almost every Zeiss lens has loCA, and it doesn't seem to affect this forum admiration for Zeiss glass.
p.18 #17 · Zeiss "Batis" AF lens line to be released for FF E-mount
Agree on this issue. The lens design community have clearly come to the same conclusion where the trade offs make sense, and this is increasingly the case. It's a low order problem, one you have good control over and can dial in what suits you.
Zeiss were fairly surprised at the level of concern about the 21mm Distagon's distortion, as they had what they felt was a good balance in that lens, back before digital, in the film era. This is true of many lenses - designers of FF format lenses aim to deliver a 'good enough' native correction, in the basket of competing factors.
All these new Sony and Zeiss lenses are made specifically for high Mp cameras, and going by the effects of the leap in available resolution with 36Mp, users will have more of a tradeable commodity for cropping, corrections of various kinds, the work you can put on an image. Native image quality sits on a stronger foundation.
Guys like Lloyd are more lens aficionados than photographers in a sense. It's a different context and perspective; the former are more purist, the latter more interested in the character and look of the final image - destination versus process. Viewers don't look forensically into the image searching for faults, they react to the content/presentation of the image. And - the best is the enemy of the good. Zeiss will sell tenfold or more Batis 85s than Otus 85s.
p.18 #18 · Zeiss "Batis" AF lens line to be released for FF E-mount
Matt Grum wrote:
Bit harsh maybe (I can't claim I fully grasp all the stereotypes from each US state), I hope jsv_20 has a sense of humour, but yes, the Zeiss Batis samples and their sometimes unusual dimensions were discussed several pages back.
I've just got back from the pub and think I've finally grasped the intricacies of distortion correcting transformations but insights will have to wait until the morning...
Matt,
it's not so much that you don't grasp the individual state stereotypes but rather the degree of seriousness in my post (to which there was none) - but that's more likely the veiling effect of the internet than anything else.....my comment was a poor attempt at a bit of humor.
p.18 #19 · Zeiss "Batis" AF lens line to be released for FF E-mount
edwardkaraa wrote:
Well, I really hate to disagree with some of the most distinguished members of this board, but to me, a high quality lens should be well corrected for all aberrations, physically I consider the need for software correction as a kind of cheating Don't crucify me for saying that, just my opinion.
.
I won't crucify you! But the thing is, you can't correct a lens for all aberrations holding the parameters of size and cost fixed. Correcting optically for distortion means the lens is *less* well corrected in some other way, usually resolution. Optical correction reduces resolution.
So you have to chose which, and how much, you want optically corrected. Of course software correction of distortion costs resolution too. But (as Roger points out at the end of his LR article about distortion correction) at least then you have the choice on a case by case basis of what to optimise for - distortion or resolution.
Notice I said holding parameters fixed. You can impressively correct for all aberrations if you are prepared to make the lens very large and very expensive. In other words, an Otus. I admire them, but I don't want a 55mm lens that large. And I can't pay for it. At any level less than Otus, you have choices to make.
If you just prefer the choice that locks in the distortion correction optically, and thus lose resolution you will never get back, that's fine. It saves the hassle of applying a profile. But I really don't see that it's *purer*. In fact I think it's less pure in that it bakes in a choice.
p.18 #20 · Zeiss "Batis" AF lens line to be released for FF E-mount
DavidBM wrote:
I won't crucify you! But the thing is, you can't correct a lens for all aberrations holding the parameters of size and cost fixed. Correcting optically for distortion means the lens is *less* well corrected in some other way, usually resolution. Optical correction reduces resolution.
So you have to chose which, and how much, you want optically corrected. Of course software correction of distortion costs resolution too. But (as Roger points out at the end of his LR article about distortion correction) at least then you have the choice on a case by case basis of what to optimise for - distortion or resolution.
Notice I said holding parameters fixed. You can impressively correct for all aberrations if you are prepared to make the lens very large and very expensive. In other words, an Otus. I admire them, but I don't want a 55mm lens that large. And I can't pay for it. At any level less than Otus, you have choices to make.
If you just prefer the choice that locks in the distortion correction optically, and thus lose resolution you will never get back, that's fine. It saves the hassle of applying a profile. But I really don't see that it's *purer*. In fact I think it's less pure in that it bakes in a choice....Show more →
I would argue that a lens like the Otus is designed for SLR, while for a mirrorless cam, there are less design restrictions. I mentioned the ZM earlier. They are small, light, and extremely well corrected with very high image quality.
and think I've finally grasped the intricacies of distortion correcting transformations but insights will have to wait until the morning...