Focus was not adjusted on stopping down, by clever positioning of the focus plane you might be able to yield slightly better results.
In short range I also found the CV 35mm 1.7 to show significant focus shift, that might also make the lens look worse than it would be when adjusting focus stopped down.
Looking forward to your full report!
How do think the corrective lenses that people are experimenting with affect these results? (Not sure anyone has tried them for the Ultron, yet, but the ZM35 is seeing quite a boost.)
Not tested the CV and ZM side by side but the CV 35 has more field curvature at least my experience with it. So softer corners. The ZM by itself hits the corners at F6.3 and the CV from memory not until F9. Both very nice lenses though. I liked the CV 35 1.7 a lot but end of day I like the ZM better. Corrective lenses work very well. I would expect it helpthe CV a lot
Parariss wrote:
Looking forward to your full report!
How do think the corrective lenses that people are experimenting with affect these results? (Not sure anyone has tried them for the Ultron, yet, but the ZM35 is seeing quite a boost.)
I have already tried the Ultron with a 5m Eksma lens: https://www.flickr.com/photos/140854680@N04/32534945762/in/dateposted/
I am still waiting for the optimal lens for the ZM 35mm 1.4 (delivery time is ~2 months, it is said to arrive on friday which I still doubt).
This will be included in the report as well, but I think the results I got with the Eksma lens on the VM 35mm 1.7 are very encouraging:
Corners wide open are lifted from junk to actually usable. There might be the tiniest hint of slightly degraded midframe at f/1.7 (not sure one would notice that using a 24mp sensor),
but from there on with filter is significantly better, still so at f/8.0.
Just to add with corrective lens all these lenses change their spots per say and get a lot better in the corners. The ZM 25 for instance with correction 2.8 looks like 5.6 without the correction lenses. That's a 2 stop improvement in the corners. So everything changes now
GMPhotography wrote:
Just to add with corrective lens all these lenses change their spots per say and get a lot better in the corners. The ZM 25 for instance with correction 2.8 looks like 5.6 without the correction lenses. That's a 2 stop improvement in the corners. So everything changes now
I've been following the thread - amazing work you all are doing there!
Focus was not adjusted on stopping down, by clever positioning of the focus plane you might be able to yield slightly better results.
In short range I also found the CV 35mm 1.7 to show significant focus shift, that might also make the lens look worse than it would be when adjusting focus stopped down.
Bastian,
Thanks for the comparison. Something is odd here though.
I've compared multiple copies of the ZM 35 vs Loxia 35, and the ZM always looks substantially better especially in the corners even without a front-lens correction. Even your center crops look very weak for the ZM.
Without the PCX 5m, these lenses should be focused towards the mid-frame but even with the PCX, it does not hurt focusing at the same location as FC is not completely corrected.
It's not my intent to knock down your test but I honestly don't believe this it represents how these lenses truly perform at infinity. I would at least re-test it or wait for the OptoSigma lens.
Fred Miranda wrote:
I've compared multiple copies of the ZM 35 vs Loxia 35, and the ZM always looks substantially better especially at the corners even without a front-lens correction.
At what apertures? At f/8.0 I would give the nod towards the ZM (without 5m) vs Loxia, but before that?
Loxia corners are far from great wide open, but ZM is just mushy because of field curvature.
With my two samples: Loxia has better corners between f/2.0 and f/5.6 (still nothing to write home about up until f/4.0),
after that it is surpassed by the ZM.
Also keep in mind as I have written before: in this comparison I did not adjust focus on stopping down so this is only valid for focusing wide open and stopping down after that.
But as soon as the OptoSigma filter arrives I have to rerun the test anyway.
Hmm, that's odd as ZM35D is very sharp in the center even wide open.
Here are few samples taken few minutes ago on Kolari modded A7R at all apertures.
Notice how central sharpness at f/1.4 compares to extreme corners at f/5.6 (differences in brightness aside)
GMPhotography wrote:
The ZM by itself hits the corners at F6.3 and the CV from memory not until F9. Both very nice lenses though.
No offence but who cares?
If you are shooting scapes f9-11 is where it's at just to get enough dof. Who cares about corner sharpness at f6.3 apart from getting hung up on test charts?
For me that pixel peeping sharpness difference at extreme corner is absolutely irrelevant and makes zero impact in real life usage. I take smaller, lighter lens at less than half the price.
By the looks of things CV is sharper than the ZM at center and mid frame.
Sure the ZM looks better stopped down at the corners, but honestly the CV is good enough, and we are pixel peeping here.
Oh I careless about mid and corner at f2.8.
I take the smaller, lighter, more agile CV at less than half price thank you.
I have both lenses that I use on an A7ii. In my experience, the CV has greater field curvature and much more color shifting and vignetting along the edges at wide apertures. However, I believe that color shifting is not an issue on the A7Rii. Also, CornerFix does a great job correcting these aberrations (not the curved field.) The ZM gives you a huge dose of micro-contrast and Zeiss pop. Also, center sharpness is biting at all apertures and is certainly the equal of my Ultron. At some point, I'm going to try a front end lens to correct field curvature.
I really like both lenses and could easily live with either, but since I got the ZM, the CV is getting very little use. The Zeiss is bigger, heavier and more expensive, but I prefer its output. It's good to have choices that are so excellent.
Really take no offense , sorry but obviously you know very little about photography and its usage in many situations where corner sharpness and more importantly field curvature causes issues with sharpness right outside the center zone. Now I'm only stating the facts when it is sharp in the corners on a ZM at F6.3 and on a CV which has more field curvature and it takes F8. I've owned the CV 35 twice now so I know the lens very well. Now take that lens take a shot filling the frame with 3 people at let's say even at F4 those two folks outside the center zone on their outside edge maybe even sooner will not be in focus. This is field curvature and if you don't understand it than your going to run into problems. Also not all landscape shooting is at F8 everytime, wish that was the case but it's not as wind, weather can and will dictate speed needed to freeze the scene. Is this the case everytime where the corners do matter , no but you need to know where your limits are , what any lens you own will do and not do. Take a looking at my website and in many cases corners matter, sometimes they don't but having a lens with field curvature will put limits sometimes on what you are shooting.
Guy I fully understand what you are saying, but as BastianK has shown the ZM isn't immune and field curvature free.
Also the CV is better than the ZM at center and mid frame.
Even with what you said is true, your example of filling 3 people at f4 with ZM will have the same issue (albeit less than CV maybe?). And if you have to tightly frame a 3 people group shots with faces near extreme edges then I am sorry that's just the incompetence of the photographer.
Looking at your website and regardless of how much the corners matter it will show ABSOLUTELY no difference in real life prints.
I know this forum is great at vigorous tests and measurebating, but sometimes it's way over the line I feel.
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kin2son wrote:
Guy I fully understand what you are saying, but as BastianK has shown the ZM isn't immune and field curvature free.
Also the CV is better than the ZM at center and mid frame.
Even with what you said is true, your example of filling 3 people at f4 with ZM will have the same issue (albeit less than CV maybe?). And if you have to tightly frame a 3 people group shots with faces near extreme edges then I am sorry that's just the incompetence of the photographer.
Looking at your website and regardless of how much the corners matter it will show ABSOLUTELY no difference no real life prints.
I know this forum is great at vigorous tests and measurebating, but sometimes it's way over the line I feel. ...Show more →
I guess I don't agree with your analysis here. If you care about real life prints any small advantage for the CV in the centre of Bastian's shots certainly won't show up for real life prints and to my eye the ZM does ever so slightly better at mid frame than the CV, but again this won't show up in real prints. What will show up in real prints in the difference in the corners even at f/8, so by the real life prints criteria the ZM would have a small but probably noticeable advantage in the corners. Is it worth the extra money and carrying the larger lens? That would depend on the person.
You should also keep in mind that Bastian's test is just one and others have found the opposite pattern in the centre, but I don't think there is much disputing that centre sharpness is similar and excellent with these two lenses.
It also matters what camera you are shooting. On a digital Leica M or a Sony with a modified sensor stack the differences will be bigger. My preference for the ZM comes down to two things that aren't tested here. First the ZM has excellent performance up close even into the macro range with extension. The CV not so much. That matters to me. Second, I like the rendering of the ZM especially the high micro contrast.
None of these things are measurebating as you call it. They are aspects of the holistic image. Now these are things important to me and others might care about other things and not share my preferences. So, of course, YMMV.
No your going to run into field curvature with both lenses one more so than the other no question about it , these are not flat field lenses right out of the gate and other lenses maybe better at this than others . The Tamron 35 1.8 for instance , dang thing is sharp into the very corners even at 2.8. But again the lens does not render anything like the CV or ZM for that matter either. It's a little clinical in look. I'm not sure I agree though the CV is better on center as Bastians test as I have not seen that to be the case. But that does not matter really the CV is a very very nice lens and yes it's cheaper and lighter. I happen to like the Zeiss look better but that's subjective for others. I do disagree about the very corners though. I printed for a long time and sure not every case but sometimes depending on subject it does. We can certainly disagree here as that is subjective as well. I find it annoying more with super wides than anything else as usually there are not people in those shots, people shots I am not so worried about the corners and actually want them soft depending on the look I want. Again depends on what your after.
Now the forum being over the top sometimes I will certainly agree but your in a gear forum and for some folks this is more about the science than the ART. That's pretty natural. I'm actually more about the ART myself. But I do think it's important and why I test everything is to know exactly where my gears limits are. I get paid to shoot and I want to know beforehand what to expect so I don't make a bad judgement call in the field. For me it's about knowing your gear, I'm maybe a little anal about it but I think that's fine if your taking that knowledge in the field and not the lab.
kin2son wrote:
Guy I fully understand what you are saying, but as BastianK has shown the ZM isn't immune and field curvature free.
Also the CV is better than the ZM at center and mid frame.
Actually, this is where I have doubts whether standard A7RM2 sensor stack and additional filter(s) at the front of the lens compromise image uniformity at the benefit of sharper corners.
kin2son wrote:
Guy I fully understand what you are saying, but as BastianK has shown the ZM isn't immune and field curvature free.
Also the CV is better than the ZM at center and mid frame.
Even with what you said is true, your example of filling 3 people at f4 with ZM will have the same issue (albeit less than CV maybe?). And if you have to tightly frame a 3 people group shots with faces near extreme edges then I am sorry that's just the incompetence of the photographer.
Looking at your website and regardless of how much the corners matter it will show ABSOLUTELY no difference in real life prints.
I know this forum is great at vigorous tests and measurebating, but sometimes it's way over the line I feel. ...Show more →
For landscapes, corners matter. Lenses are often at their best at F5.6 and diffraction starts being noticeable at F11. I want to have the best output my camera and lens can make. I will often focus stack to avoid having to stop down too much. Sometime I need faster shutter speeds and value across the frame output at larger apertures. IF you like the CV better, enjoy. By all means post examples and show how great it is. However, many here seem to prefer the ZM for any number of valid reasons.
Generally, the discourse here is civil and folks avoid name calling. Referencing the supposed "incompetence of the photographer" (Guy is a pro and very knowledgeable) and alleging the whole forum is "way over the line" and "measurebating" is perhaps not the best approach. This is a gear forum after all and folks here take testing and discussing the pro's and cons seriously. Pixel peeping is normal. Every lens is a compromise. Just because you find the CV's compromises more to your liking does not mean that others are wrong, incompetent, or a measurebator.
You prefer using manual focusing anyways?