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Archive 2018Zeiss Loxia 25mm f2.4 is a distagon
p.17 #1Zeiss Loxia 25mm f2.4 is a distagon
Steve Spencer wrote:
I have and like B25; but the LoCA is if anything a bit worse than the new Loxia as far as I can tell without testing them both together. And the published MTF tells be the Loxia should resolve even better than my Batis.Showing traces at f/8 as well:
https://www.fredmiranda.com/forum/topic/1529721/14#14418360Yes, but in this test the lens was deliberately misfocused behind the subject. I am not sure how often the problems seen here would show up in real world shooting. I agree that the CA is less than ideal and a potential problem. It probably is the result of using less special glass in this lens. I also agree with Samuli and Phillip that I probably prefer having this CA problem and the nice bokeh and good sharpness than a lens with less CA and not as nice of bokeh.
As a test, it was mis-focused in order to demonstrate a possible issue. These are 1:1 crops and I agree should not be much of an issue in real shooting...especially when using it for landscape photography where LaCA matter more than LoCA.
Overall from what I've seen, the Loxia 25/2.4 draws very nicely and it's not too expensive. There must be a compromise somewhere and I think it's useful to know what the negatives are. Hopefully I will get my hands on one soon but it looks like there will be a delay for the US market.
I confess that I was taken back by the slight inferior color correction when compared to the Loxia 21 but that's just one aspect this lens' overall image quality and rendering.
Fred Miranda wrote
DavidBM wrote
GMPhotography wrote
I bailed for now bought a used Batis 25 for now. But I will visit this again once it’s actually on the shelves.https://www.fredmiranda.com/forum/topic/1529721/14#14418360
As a test, it was mis-focused in order to demonstrate a possible issue. These are 1:1 crops and I agree should not be much of an issue in real shooting...especially when using it for landscape photography where LaCA matter more than LoCA.
Overall from what I've seen, the Loxia 25/2.4 draws very nicely and it's not too expensive. There must be a compromise somewhere and I think it's useful to know what the negatives are. Hopefully I will get my hands on one soon but it looks like there will be a delay for the US market.
I confess that I was taken back by the slight inferior color correction when compared to the Loxia 21 but that's just one aspect this lens' overall image quality and rendering.
Mar 30, 2018 at 07:00 PM
p.17 #2Zeiss Loxia 25mm f2.4 is a distagon
One last CA comparison from me, this time comparing Loxia 25 with Milvus 25 (zf.2 adapted), first at F2.8 and then F8. Focused here to induce both purple and green loCA at f2.8 (and not re-adjusted for F8).
Because there was no electronic communication between the adapted Milvus zf.2 and A7RII, there is no custom profile attached to the Milvus raw file. That means that, unlike with the Loxia, camera raw doesn't automatically apply CA corrections for the Milvus, so for that case I manually checked the "reduce CA" option.
Loxia 25 F2.8 A7RII 100% crop
Milvus 25 F2.8 A7RII 100% crop
Loxia 25 F8 A7RII 100% crop
Milvus 25 F8 A7RII 100% crop
Because there was no electronic communication between the adapted Milvus zf.2 and A7RII, there is no custom profile attached to the Milvus raw file. That means that, unlike with the Loxia, camera raw doesn't automatically apply CA corrections for the Milvus, so for that case I manually checked the "reduce CA" option.
Loxia 25 F2.8 A7RII 100% crop
Milvus 25 F2.8 A7RII 100% crop
Loxia 25 F8 A7RII 100% crop
Milvus 25 F8 A7RII 100% crop
Mar 30, 2018 at 09:28 PM
p.17 #3Zeiss Loxia 25mm f2.4 is a distagon
Did anybody compare the Loxia 25 to a C/Y 2.8 28, C/Y 2.0 28 or Pentax SMC K 3.5 28mm? rendering? sharpness? purple frindge? How big is the difference? Is it worth to switch to the Loxia 25mm from those alt glass lenses?
Mar 30, 2018 at 10:59 PM
p.17 #4Zeiss Loxia 25mm f2.4 is a distagon
rvh23 wrote:
One last CA comparison from me, this time comparing Loxia 25 with Milvus 25 (zf.2 adapted), first at F2.8 and then F8. Focused here to induce both purple and green loCA at f2.8 (and not re-adjusted for F8).
Because there was no electronic communication between the adapted Milvus zf.2 and A7RII, there is no custom profile attached to the Milvus raw file. That means that, unlike with the Loxia, camera raw doesn't automatically apply CA corrections for the Milvus, so for that case I manually checked the "reduce CA" option.
Interesting. CA close enough to make that not a factor in my choice between Milvus and Loxia; it'd be just whether I wanted the speed of Milvus or the portability of Loxia, other things being equal.
But those F8 crops....were the lighting conditions different? Lox seems contrastier.
One last CA comparison from me, this time comparing Loxia 25 with Milvus 25 (zf.2 adapted), first at F2.8 and then F8. Focused here to induce both purple and green loCA at f2.8 (and not re-adjusted for F8).
Because there was no electronic communication between the adapted Milvus zf.2 and A7RII, there is no custom profile attached to the Milvus raw file. That means that, unlike with the Loxia, camera raw doesn't automatically apply CA corrections for the Milvus, so for that case I manually checked the "reduce CA" option.
Interesting. CA close enough to make that not a factor in my choice between Milvus and Loxia; it'd be just whether I wanted the speed of Milvus or the portability of Loxia, other things being equal.
But those F8 crops....were the lighting conditions different? Lox seems contrastier.
Mar 30, 2018 at 11:07 PM
p.17 #5Zeiss Loxia 25mm f2.4 is a distagon
Fred Miranda wrote:
I have and like B25; but the LoCA is if anything a bit worse than the new Loxia as far as I can tell without testing them both together. And the published MTF tells be the Loxia should resolve even better than my Batis.Showing traces at f/8 as well:
https://www.fredmiranda.com/forum/topic/1529721/14#14418360Yes, but in this test the lens was deliberately misfocused behind the subject. I am not sure how often the problems seen here would show up in real world shooting. I agree that the CA is less than ideal and a potential problem. It probably is the result of using less special glass in this lens. I also agree with Samuli and Phillip that I probably prefer having this CA problem and the nice bokeh and good sharpness than a lens with less CA and not as nice of bokeh.I confess that I was taken back by the slight inferior color correction when compared to the Loxia 21 but that's just one aspect this lens' overall image quality and rendering.
I guess other things being equal I would expect worse LoCA on a slightly longer lens, and worse LaCA on a slightly wider one.
Steve Spencer wrote
Fred Miranda wrote
DavidBM wrote
GMPhotography wrote
I bailed for now bought a used Batis 25 for now. But I will visit this again once it’s actually on the shelves.https://www.fredmiranda.com/forum/topic/1529721/14#14418360
I guess other things being equal I would expect worse LoCA on a slightly longer lens, and worse LaCA on a slightly wider one.
Mar 30, 2018 at 11:09 PM
p.17 #6Zeiss Loxia 25mm f2.4 is a distagon
DavidBM wrote:
Because there was no electronic communication between the adapted Milvus zf.2 and A7RII, there is no custom profile attached to the Milvus raw file. That means that, unlike with the Loxia, camera raw doesn't automatically apply CA corrections for the Milvus, so for that case I manually checked the "reduce CA" option.But those F8 crops....were the lighting conditions different? Lox seems contrastier.
I see that as well. The Milvus also seems slightly warmer but that's only valid if the white balance was identical for both shots.
rvh23 wrote
One last CA comparison from me, this time comparing Loxia 25 with Milvus 25 (zf.2 adapted), first at F2.8 and then F8. Focused here to induce both purple and green loCA at f2.8 (and not re-adjusted for F8).Because there was no electronic communication between the adapted Milvus zf.2 and A7RII, there is no custom profile attached to the Milvus raw file. That means that, unlike with the Loxia, camera raw doesn't automatically apply CA corrections for the Milvus, so for that case I manually checked the "reduce CA" option.
I see that as well. The Milvus also seems slightly warmer but that's only valid if the white balance was identical for both shots.
Mar 30, 2018 at 11:52 PM
p.17 #7Zeiss Loxia 25mm f2.4 is a distagon
Yes, the loCA seems very similar to me too betwen the Milvus and Loxia 25. I take it to mean that the difference between Loxia 25 and 21 in this regard is more due to the 21 being exceptional, rather than the 25 being poor.
Regarding the contrast and color variation, in this case that might be confounded by the sun being not far from the edge of the frame and getting into the larger front glass of the Milvus more than the Loxia (no hood used with either lens). All my posted shots here are at fixed daylight white balance. In the small full frame comparison images here the color balance looks fairly close to me.
Having said that, when I first tested the Milvus, I did see lower far corner contrast than the Loxia 21 for nearby focus in a quick test I did, but I have yet to investigate that more thoroughly.
Regarding the contrast and color variation, in this case that might be confounded by the sun being not far from the edge of the frame and getting into the larger front glass of the Milvus more than the Loxia (no hood used with either lens). All my posted shots here are at fixed daylight white balance. In the small full frame comparison images here the color balance looks fairly close to me.
Having said that, when I first tested the Milvus, I did see lower far corner contrast than the Loxia 21 for nearby focus in a quick test I did, but I have yet to investigate that more thoroughly.
Mar 31, 2018 at 12:25 AM
p.17 #8Zeiss Loxia 25mm f2.4 is a distagon
How is the coma with the Milvus?
Mar 31, 2018 at 01:27 AM
p.17 #9Zeiss Loxia 25mm f2.4 is a distagon
Below is a side by side comparison of corner sharpness/contrast for Loxia 21, Loxia 25 and Milvus 25, all at F5.6, and with a subject distance of about 2m. These are 100% crops at the most extreme corner section of the frame that still allows maximal zoomed-in magnification for focusing on A7RII, which is not quite the actual corner of the frame. Focus adjusted for corner sharpness on each shot, best of three repeats with each lens. All shots were at the same shutter speed. Minimal sharpening (camera raw default) applied to facilitate the comparison. Slight cyan cast is because of the use of daylight balance for a shot taken in the shade.
The take home for me here is that all three lenses are very good in terms of corner sharpness, likely with very little to delineate them in real world images. The Milvus does show an advantage in terms of corner brightness.
* please ignore the black rectangles. I blacked them out in post after realizing they can infer a delivery address that I shouldn't be publishing
Edited on Mar 31, 2018 at 08:10 PM · View previous versions
The take home for me here is that all three lenses are very good in terms of corner sharpness, likely with very little to delineate them in real world images. The Milvus does show an advantage in terms of corner brightness.
* please ignore the black rectangles. I blacked them out in post after realizing they can infer a delivery address that I shouldn't be publishing
Edited on Mar 31, 2018 at 08:10 PM · View previous versions
Mar 31, 2018 at 03:06 AM
p.17 #11Zeiss Loxia 25mm f2.4 is a distagon
Some more heavily edited images:
The more I use it, the more I like it.
I will certainly wait for Bastian's comparison with the L21 but at the moment I think I would be served better by the L25 since I enjoy playing with bokeh a lot more than I would have anticipated and 25 mm work very well for my forest photography.
The more I use it, the more I like it.
I will certainly wait for Bastian's comparison with the L21 but at the moment I think I would be served better by the L25 since I enjoy playing with bokeh a lot more than I would have anticipated and 25 mm work very well for my forest photography.
Mar 31, 2018 at 10:03 AM
p.17 #12Zeiss Loxia 25mm f2.4 is a distagon
This almost makes me want to buy a Llama!
Great shot and nice bokeh :-)
Great shot and nice bokeh :-)
Mar 31, 2018 at 10:40 AM
p.17 #13Zeiss Loxia 25mm f2.4 is a distagon
Here is an estimate of the focus breathing (change in FOV with focal adjustment) with the Loxia 25, and for comparison Milvus 25. One reason I was interested in this is that less breathing may improve focus stacking over extreme focal ranges, especially when including very close foreground.
I'm not sure if there is a more standard way measure it, but I just stuck a black 8"x10" rectangle with a 4x5 cutout on a wall (under warm light producing the orange background). Then, first with the lens focused at minimum focus distance, I moved the lens/camera so the rectangle just fit in the frame. I then adjusted focus, and readjusted the lens/camera position. Finally I refocused and took the "close focus shot". The distance to the rectangle was in the vicinity of 0.3m. I then adjusted focus to infinity, and took the "infinity" shot.
The main interest is in the change in size of the rectangle, reflecting focus breathing. The less change in size, the less breathing. It's clear that there is quite a bit of breathing in the Loxia, I would estimate the width of the rectangle changes by about 10% when focus changes from about 0.3m to infinity. I tested the Loxia 21 also but it looks pretty much identical to the 25, so I haven't included those shots. The Milvus shows less breathing, I estimate its change in rectangle width to be only about 3-4%.
These shots are not well suited to assess distortion as the rectangle wasn't strictly flush with the wall due to the blue tack holding it up. All shots were taken with the same camera settings and apertures for both lenses at F8.
I'm not sure if there is a more standard way measure it, but I just stuck a black 8"x10" rectangle with a 4x5 cutout on a wall (under warm light producing the orange background). Then, first with the lens focused at minimum focus distance, I moved the lens/camera so the rectangle just fit in the frame. I then adjusted focus, and readjusted the lens/camera position. Finally I refocused and took the "close focus shot". The distance to the rectangle was in the vicinity of 0.3m. I then adjusted focus to infinity, and took the "infinity" shot.
The main interest is in the change in size of the rectangle, reflecting focus breathing. The less change in size, the less breathing. It's clear that there is quite a bit of breathing in the Loxia, I would estimate the width of the rectangle changes by about 10% when focus changes from about 0.3m to infinity. I tested the Loxia 21 also but it looks pretty much identical to the 25, so I haven't included those shots. The Milvus shows less breathing, I estimate its change in rectangle width to be only about 3-4%.
These shots are not well suited to assess distortion as the rectangle wasn't strictly flush with the wall due to the blue tack holding it up. All shots were taken with the same camera settings and apertures for both lenses at F8.
Apr 02, 2018 at 07:18 AM
p.17 #14Zeiss Loxia 25mm f2.4 is a distagon
rvh23 wrote:
Here is an estimate of the focus breathing (change in FOV with focal adjustment) with the Loxia 25, and for comparison Milvus 25. One reason I was interested in this is that less breathing may improve focus stacking over extreme focal ranges, especially when including very close foreground.
I'm not sure if there is a more standard way measure it, but I just stuck a black 8"x10" rectangle with a 4x5 cutout on a wall (under warm light producing the orange background). Then, first with the lens focused at minimum focus distance, I moved the lens/camera so the rectangle just fit...Show more →
Great job rvh23! Enlightening tests.
Here is an estimate of the focus breathing (change in FOV with focal adjustment) with the Loxia 25, and for comparison Milvus 25. One reason I was interested in this is that less breathing may improve focus stacking over extreme focal ranges, especially when including very close foreground.
I'm not sure if there is a more standard way measure it, but I just stuck a black 8"x10" rectangle with a 4x5 cutout on a wall (under warm light producing the orange background). Then, first with the lens focused at minimum focus distance, I moved the lens/camera so the rectangle just fit...Show more →
Great job rvh23! Enlightening tests.
Apr 02, 2018 at 09:50 AM
p.17 #15Zeiss Loxia 25mm f2.4 is a distagon
Thanks Fred. Looks like you got your 28 after all, at least for close focus... 
Apr 02, 2018 at 04:37 PM
p.17 #16Zeiss Loxia 25mm f2.4 is a distagon
rvh23 wrote:
Below is a side by side comparison of corner sharpness/contrast for Loxia 21, Loxia 25 and Milvus 25, all at F5.6, and with a subject distance of about 2m. These are 100% crops at the most extreme corner section of the frame that still allows maximal zoomed-in magnification for focusing on A7RII, which is not quite the actual corner of the frame. Focus adjusted for corner sharpness on each shot, best of three repeats with each lens. All shots were at the same shutter speed. Minimal sharpening (camera raw default) applied to facilitate the comparison. Slight cyan cast is because...Show more →
Loxia 21 looks to have better contrast at the corner than the Loxia 25
Below is a side by side comparison of corner sharpness/contrast for Loxia 21, Loxia 25 and Milvus 25, all at F5.6, and with a subject distance of about 2m. These are 100% crops at the most extreme corner section of the frame that still allows maximal zoomed-in magnification for focusing on A7RII, which is not quite the actual corner of the frame. Focus adjusted for corner sharpness on each shot, best of three repeats with each lens. All shots were at the same shutter speed. Minimal sharpening (camera raw default) applied to facilitate the comparison. Slight cyan cast is because...Show more →
Loxia 21 looks to have better contrast at the corner than the Loxia 25
Apr 03, 2018 at 12:31 AM
p.17 #17Zeiss Loxia 25mm f2.4 is a distagon
Can you point out where you see the contrast difference in that comparison? To me, all three lenses look very similar.
Apr 03, 2018 at 01:00 AM
p.17 #18Zeiss Loxia 25mm f2.4 is a distagon
angle of view
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Apr 03, 2018 at 03:01 AM
p.17 #19Zeiss Loxia 25mm f2.4 is a distagon
FYI, Lightroom update out today, with profile for the Loxia 25mm.
Apr 03, 2018 at 07:33 AM
p.17 #20Zeiss Loxia 25mm f2.4 is a distagon
The Loxia 25 is holding the straight lines very well in that sample
Apr 03, 2018 at 07:36 AM