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Archive 2015Zeiss Unveils the Loxia 21mm f/2.8
p.21 #1Zeiss Unveils the Loxia 21mm f/2.8
Regarding distortion, Christophe Casenave told me the Loxia has less than the "classic". One of the reasons why Zeiss feel it is a superior lens.
Regarding decentering, I wonder whether the mount changes have something to do with it.
Regarding decentering, I wonder whether the mount changes have something to do with it.
Dec 20, 2015 at 11:41 AM
p.21 #2Zeiss Unveils the Loxia 21mm f/2.8
Jannik, I wondered a bit about the coma sample you showed yesterday. I thought there was less coma in the upper right part of the image than in the rest. However I didn't know if all the lights were in a plane parallell to the focus plane. I agree that we shall wait to conclude about coma until the lens is fixed.
Thanks for a thorough review so far.
I hope Zeiss in Oberkochen can fix your lens quickly. They are usually quick to fix things.
Thanks for a thorough review so far.
I hope Zeiss in Oberkochen can fix your lens quickly. They are usually quick to fix things. Dec 20, 2015 at 12:05 PM
p.21 #3Zeiss Unveils the Loxia 21mm f/2.8
Jannik Peters wrote:
The wavy distortion looks stronger than ZE/ZF 21.
Is that true?I didn't have the Milvus so far but there should be broad experience here so that I hope someone will judge that.
Good examination. Yesterday, I could put my Loxia out in daylight for the first time and found out immediately, that it is decentered. I will post some corner crops that show the decentering. It is definitely the lens because my Loxia 2/50 performs equal in all edges. I decided to pause that review until I get a proper copy of it. I'm really disappointed. I have a ~50% decentering rate with my Sony and Zeiss new lens purchases,...Show more →
I have been having some difficulty discovering if mine is decentered (but I don't think it is) as I tend to shoot in my normal way rather than do brick wall type tests. Why I say this as I have been finding that it is a bit of a learning curve with distant objects getting sharpness across the frame due to some probable field curvature and the very short focus-throw between 2m and infinity. As I said I don't think it is but I have some doubts and will have to investigate further.
wayne seltzer wrote
A wide angle lens review without corner crops of a planar or distant subject.The wavy distortion looks stronger than ZE/ZF 21.
Is that true?
Good examination. Yesterday, I could put my Loxia out in daylight for the first time and found out immediately, that it is decentered. I will post some corner crops that show the decentering. It is definitely the lens because my Loxia 2/50 performs equal in all edges. I decided to pause that review until I get a proper copy of it. I'm really disappointed. I have a ~50% decentering rate with my Sony and Zeiss new lens purchases,...Show more →
I have been having some difficulty discovering if mine is decentered (but I don't think it is) as I tend to shoot in my normal way rather than do brick wall type tests. Why I say this as I have been finding that it is a bit of a learning curve with distant objects getting sharpness across the frame due to some probable field curvature and the very short focus-throw between 2m and infinity. As I said I don't think it is but I have some doubts and will have to investigate further.
Dec 20, 2015 at 12:07 PM
p.21 #4Zeiss Unveils the Loxia 21mm f/2.8
Viramati wrote:
I have been having some difficulty discovering if mine is decentered (but I don't think it is) as I tend to shoot in my normal way rather than do brick wall type tests.
I test the decentering like that. It is very fast and works fine (hope you can translate it):
http://www.gletscherbruch.de/foto/test/dezentrierung/dezentrierung.html
I have been having some difficulty discovering if mine is decentered (but I don't think it is) as I tend to shoot in my normal way rather than do brick wall type tests.
I test the decentering like that. It is very fast and works fine (hope you can translate it):
http://www.gletscherbruch.de/foto/test/dezentrierung/dezentrierung.html
Dec 20, 2015 at 12:09 PM
p.21 #5Zeiss Unveils the Loxia 21mm f/2.8
Thanks for posting your review and hope you get a non-decentered one soon!
Jannik Peters wrote:
The wavy distortion looks stronger than ZE/ZF 21.
Is that true?I didn't have the Milvus so far but there should be broad experience here so that I hope someone will judge that.
Good examination. Yesterday, I could put my Loxia out in daylight for the first time and found out immediately, that it is decentered. I will post some corner crops that show the decentering. It is definitely the lens because my Loxia 2/50 performs equal in all edges. I decided to pause that review until I get a proper copy of it. I'm really disappointed. I have a ~50% decentering rate with my Sony and Zeiss new lens purchases,...Show more →
Jannik Peters wrote:
wayne seltzer wrote
A wide angle lens review without corner crops of a planar or distant subject.The wavy distortion looks stronger than ZE/ZF 21.
Is that true?
Good examination. Yesterday, I could put my Loxia out in daylight for the first time and found out immediately, that it is decentered. I will post some corner crops that show the decentering. It is definitely the lens because my Loxia 2/50 performs equal in all edges. I decided to pause that review until I get a proper copy of it. I'm really disappointed. I have a ~50% decentering rate with my Sony and Zeiss new lens purchases,...Show more →
Dec 20, 2015 at 12:11 PM
p.21 #6Zeiss Unveils the Loxia 21mm f/2.8
We have been told by the reputable Roger Cicala how adapters are very susceptible to giving trouble on the A7 due to the very short flange distance. A need for precision down to the micron level was mentioned.This is why I think that changing out the mount and then finding out that one can non longer focus to infinity can be a source of such problems.
Edited on Dec 20, 2015 at 12:13 PM · View previous versions
Edited on Dec 20, 2015 at 12:13 PM · View previous versions
Dec 20, 2015 at 12:12 PM
p.21 #7Zeiss Unveils the Loxia 21mm f/2.8
philber wrote:
Regarding decentering, I wonder whether the mount changes have something to do with it.
Philippe, I was unsure too. That's why I did the same test with the Loxia 2/50. Both scenes were taken with the original mount after the change from the Tough E Mount.
Here are the two samples, both taken wide open:
The bottom of Loxia 2/50 is slightly weaker than top probably because of my wobbly original mount. I think the decentering of the 2.8/21mm is pretty obvious and significant here although top left and bottom right look ok to me.
Regarding decentering, I wonder whether the mount changes have something to do with it.
Philippe, I was unsure too. That's why I did the same test with the Loxia 2/50. Both scenes were taken with the original mount after the change from the Tough E Mount.
Here are the two samples, both taken wide open:
The bottom of Loxia 2/50 is slightly weaker than top probably because of my wobbly original mount. I think the decentering of the 2.8/21mm is pretty obvious and significant here although top left and bottom right look ok to me.
Dec 20, 2015 at 12:12 PM
p.21 #8Zeiss Unveils the Loxia 21mm f/2.8
Well, I am suposed to be getting my own copy pretty soon, so I wil try it out and report.
Dec 20, 2015 at 12:24 PM
p.21 #9Zeiss Unveils the Loxia 21mm f/2.8
philber wrote:
Well, I am suposed to be getting my own copy pretty soon, so I wil try it out and report.
Looking forward for that. I already enjoyed yours and Pascal's review on dearsusans.
Well, I am suposed to be getting my own copy pretty soon, so I wil try it out and report.
Looking forward for that. I already enjoyed yours and Pascal's review on dearsusans.
Dec 20, 2015 at 12:26 PM
p.21 #10Zeiss Unveils the Loxia 21mm f/2.8
Jannik Peters wrote:
I test the decentering like that. It is very fast and works fine (hope you can translate it):
http://www.gletscherbruch.de/foto/test/dezentrierung/dezentrierung.html
I'm afraid a don't speak German so it would be great if you could give a brief synopsis. Thanks
Viramati wrote
I have been having some difficulty discovering if mine is decentered (but I don't think it is) as I tend to shoot in my normal way rather than do brick wall type tests.http://www.gletscherbruch.de/foto/test/dezentrierung/dezentrierung.html
I'm afraid a don't speak German so it would be great if you could give a brief synopsis. Thanks
Dec 20, 2015 at 12:27 PM
p.21 #11Zeiss Unveils the Loxia 21mm f/2.8
It says that, to test for decentering, you shoot a distant target, minimum 20m away, focus manually with your camera on a tripod with cable release or timer. Then, move the camera so that the (relatively small but with sharp components) target is in each corner successively, so that you can compare the 4 shots, each one is focused correctly. Comparison between the 2 sides will show decentering. In the example in the article, left-hand shots are notably less sharp than right-hand ones.
Dec 20, 2015 at 12:34 PM
p.21 #12Zeiss Unveils the Loxia 21mm f/2.8
Viramati wrote:
I'm afraid a don't speak German so it would be great if you could give a brief synopsis. Thanks
1) Turn your camera to manual exposure mode and set the lighting. Place your camera on a tripod and use self timer.
2) Place a distant (>100m away) subject in one edge of the frame.
3) Focus on it and don't change the focus anymore.
4) Now take pictures of that subject in every corner like it's shown in the link.
5) Compare the edges with the subject in every of the four pictures. With a well centered lens, every corner should look the same.
Most lenses are not 100% exactely centered but there are some very bad lenses (not only Sony or Zeiss!) out there so this check is a very basic one to me after every lens purchase.
I'm afraid a don't speak German so it would be great if you could give a brief synopsis. Thanks
1) Turn your camera to manual exposure mode and set the lighting. Place your camera on a tripod and use self timer.
2) Place a distant (>100m away) subject in one edge of the frame.
3) Focus on it and don't change the focus anymore.
4) Now take pictures of that subject in every corner like it's shown in the link.
5) Compare the edges with the subject in every of the four pictures. With a well centered lens, every corner should look the same.
Most lenses are not 100% exactely centered but there are some very bad lenses (not only Sony or Zeiss!) out there so this check is a very basic one to me after every lens purchase.
Dec 20, 2015 at 12:34 PM
p.21 #13Zeiss Unveils the Loxia 21mm f/2.8
wayne seltzer wrote:
A wide angle lens review without corner crops of a planar or distant subject.
The wavy distortion looks stronger than ZE/ZF 21.
Is that true?
Well we already knew that it is a very sharp lens, didn't we? So Jannik and I decided to first focus on those aspects which hadn't been covered by reviewers who had been provided with an early copy by Zeiss.
I think Jannik showed that the vignetting data from Zeiss is after camera correction. Zeiss doesn't mention this in their data sheet.
Steve Spencer wrote:
The wavy distortion looks stronger than ZE/ZF 21.
Is that true?No its about the same on the Zeiss MTF charts. The Loxia is about 2.1% whereas the ZE/ZF/MIlvus is about 2.3%. They have about the same barrel distortion in the middle 2/3rds (the Loxia has a bit less) but the ZE/ZF/Milvus has quite a bit more pincushion in the corners.
I checked their data sheet and I find it very curious that Zeiss gives the distortion data for the ZE/ZF Distagon at infinity but at a distance of 0.75m (!) for the Loxia. I wonder why they do that. Maybe it is worse at infinity?
I am very disappointed by the decentering of Jannik's copy. It takes about 5 minutes to detect decentering of that degree but Zeiss shipped that copy for 1499€ none the less.
Apart from that disappointment and the price there is little to not like about the Loxia.
A wide angle lens review without corner crops of a planar or distant subject.
The wavy distortion looks stronger than ZE/ZF 21.
Is that true?
Well we already knew that it is a very sharp lens, didn't we? So Jannik and I decided to first focus on those aspects which hadn't been covered by reviewers who had been provided with an early copy by Zeiss.
I think Jannik showed that the vignetting data from Zeiss is after camera correction. Zeiss doesn't mention this in their data sheet.
Steve Spencer wrote:
wayne seltzer wrote
A wide angle lens review without corner crops of a planar or distant subject.The wavy distortion looks stronger than ZE/ZF 21.
Is that true?
I checked their data sheet and I find it very curious that Zeiss gives the distortion data for the ZE/ZF Distagon at infinity but at a distance of 0.75m (!) for the Loxia. I wonder why they do that. Maybe it is worse at infinity?
I am very disappointed by the decentering of Jannik's copy. It takes about 5 minutes to detect decentering of that degree but Zeiss shipped that copy for 1499€ none the less.
Apart from that disappointment and the price there is little to not like about the Loxia.
Dec 20, 2015 at 01:36 PM
p.21 #14Zeiss Unveils the Loxia 21mm f/2.8
Phillip Reeve wrote:
The wavy distortion looks stronger than ZE/ZF 21.
Is that true?Well we already knew that it is a very sharp lens, didn't we? So Jannik and I decided to first focus on those aspects which hadn't been covered by reviewers who had been provided with an early copy by Zeiss.
I think Jannik showed that the vignetting data from Zeiss is after camera correction. Zeiss doesn't mention this in their data sheet.
The wavy distortion looks stronger than ZE/ZF 21.
Is that true?No its about the same on the Zeiss MTF charts. The Loxia is about 2.1% whereas the ZE/ZF/MIlvus is about 2.3%. They have about the same barrel distortion in the middle 2/3rds (the Loxia has a bit less) but the ZE/ZF/Milvus has quite a bit more pincushion in the corners.I checked their data sheet and I find it very curious that Zeiss gives the distortion data for the ZE/ZF Distagon at infinity but at a distance of 0.75m (!) for the Loxia. I wonder why they do that....Show more →
I didn't notice that the Loxia 21 distortion test isn't at infinity. Thanks for pointing that out. I suspect they did that so that the moustache distortion wouldn't be as obvious. Typically as you go from infinity to close focus you get more barrel and less pincushion distortion. That would suggest more moustache at infinity (more pincushion in the corners). I know it works that way for the ZE/ZF/Milvus 21 f/2.8. It has almost totally barrel distortion close up, but the moustache distortion it is know for at infinity.
wayne seltzer wrote
A wide angle lens review without corner crops of a planar or distant subject.The wavy distortion looks stronger than ZE/ZF 21.
Is that true?
I think Jannik showed that the vignetting data from Zeiss is after camera correction. Zeiss doesn't mention this in their data sheet.
Steve Spencer wrote
wayne seltzer wrote
A wide angle lens review without corner crops of a planar or distant subject.The wavy distortion looks stronger than ZE/ZF 21.
Is that true?
I didn't notice that the Loxia 21 distortion test isn't at infinity. Thanks for pointing that out. I suspect they did that so that the moustache distortion wouldn't be as obvious. Typically as you go from infinity to close focus you get more barrel and less pincushion distortion. That would suggest more moustache at infinity (more pincushion in the corners). I know it works that way for the ZE/ZF/Milvus 21 f/2.8. It has almost totally barrel distortion close up, but the moustache distortion it is know for at infinity.
Dec 20, 2015 at 02:41 PM
p.21 #15Zeiss Unveils the Loxia 21mm f/2.8
Well, if the Loxia 21 has more distortion than the "classic", and Zeiss are masking that by moving the goalposts, then it means that Casenave lied to my face, and that would be both surprising and disappointing. Until proven otherwise, I choose to believe him.
If I had to guess, the only way my learned colleagues and Casenave could all be right, and that is pure speculation, I would say that the Loxia may have more distortion SOOL (straight-out-of-lens), but that the A7, the only camera with which it can be used, corrects for it, giving the user less distortion in the pictures. That could help to explain why the Loxia is unexpectedly small for a 21mm f:2.8 whereas other new Zeiss releases (Milvus) are not exactly setting newstandards of compactness.
Please note, this is a guess, and I have used "could" and "may" several times. Or, as SAR would say, SR2...
If I had to guess, the only way my learned colleagues and Casenave could all be right, and that is pure speculation, I would say that the Loxia may have more distortion SOOL (straight-out-of-lens), but that the A7, the only camera with which it can be used, corrects for it, giving the user less distortion in the pictures. That could help to explain why the Loxia is unexpectedly small for a 21mm f:2.8 whereas other new Zeiss releases (Milvus) are not exactly setting newstandards of compactness.
Please note, this is a guess, and I have used "could" and "may" several times. Or, as SAR would say, SR2...
Dec 20, 2015 at 03:39 PM
p.21 #16Zeiss Unveils the Loxia 21mm f/2.8
philber wrote:
Well, if the Loxia 21 has more distortion than the "classic", and Zeiss are masking that by moving the goalposts, then it means that Casenave lied to my face, and that would be both surprising and disappointing. Until proven otherwise, I choose to believe him.
If I had to guess, the only way my learned colleagues and Casenave could all be right, and that is pure speculation, I would say that the Loxia may have more distortion SOOL (straight-out-of-lens), but that the A7, the only camera with which it can be used, corrects for it, giving the user less distortion in...Show more →
Jannik checked it and there is no distortion correction applied to the raw.
Well, if the Loxia 21 has more distortion than the "classic", and Zeiss are masking that by moving the goalposts, then it means that Casenave lied to my face, and that would be both surprising and disappointing. Until proven otherwise, I choose to believe him.
If I had to guess, the only way my learned colleagues and Casenave could all be right, and that is pure speculation, I would say that the Loxia may have more distortion SOOL (straight-out-of-lens), but that the A7, the only camera with which it can be used, corrects for it, giving the user less distortion in...Show more →
Jannik checked it and there is no distortion correction applied to the raw.
Dec 20, 2015 at 03:47 PM
p.21 #17Zeiss Unveils the Loxia 21mm f/2.8
I will contact him tomorrow and ask for his comments.
Dec 20, 2015 at 03:50 PM
p.21 #18Zeiss Unveils the Loxia 21mm f/2.8
Just to chime in on the question regarding distortion - at the moment I have both the ZF21mm and the Loxia 21mm.
The 'classic' is so amazing - that I am hesitating to let it go and sell it. Therefore I wanted to test anyway, so I happen to have a boring building comparison at hand.
First the Classic:
ZF21mm by Hans van den Bosch, on Flickr
And here's the Loxia:
Loxia21mm by Hans van den Bosch, on Flickr
I've double checked and all in-camera lens corrections are switched off.
Btw - those in camera corrections seem very convenient to me. Do they come at a penalty? Should I switch them of and use PTlens?
The 'classic' is so amazing - that I am hesitating to let it go and sell it. Therefore I wanted to test anyway, so I happen to have a boring building comparison at hand.
First the Classic:
ZF21mm by Hans van den Bosch, on FlickrAnd here's the Loxia:
Loxia21mm by Hans van den Bosch, on FlickrI've double checked and all in-camera lens corrections are switched off.
Btw - those in camera corrections seem very convenient to me. Do they come at a penalty? Should I switch them of and use PTlens?
Dec 21, 2015 at 05:55 AM
p.21 #19Zeiss Unveils the Loxia 21mm f/2.8
JocoFoto wrote:
Just to chime in on the question regarding distortion - at the moment I have both the ZF21mm and the Loxia 21mm.
Thanks. This is exactly what I want to know.
Just to chime in on the question regarding distortion - at the moment I have both the ZF21mm and the Loxia 21mm.
Thanks. This is exactly what I want to know.
Dec 21, 2015 at 06:30 AM
p.21 #20Zeiss Unveils the Loxia 21mm f/2.8
Jannik Peters wrote:
Philippe, I was unsure too. That's why I did the same test with the Loxia 2/50. Both scenes were taken with the original mount after the change from the Tough E Mount.
Here are the two samples, both taken wide open:
https://farm6.staticflickr.com/5785/23845331816_bcfd0da37e_o.jpg
https://farm6.staticflickr.com/5816/23871437425_bf9597bea7_o.jpg
The bottom of Loxia 2/50 is slightly weaker than top probably because of my wobbly original mount. I think the decentering of the 2.8/21mm is pretty obvious and significant here although top left and bottom right look ok to me.
I think you may be looking at a decentered lens in the case of the Loxia 21/2.8. I had a decentered ZF.2 18/3.5, and there were "zones" of sharpnes and unsharpness that didn't correspond to a simple out-of-focus. The good news is that Zeiss in Oberkochen could fix it quickly for me. That lens I had bought used, and it looked like it had never been out of the box. I shot it exclusively with a Sony A7 and a Voigtländer adapter. When it came back everything was top notch. And the ZF.2 18/3.5 is defintely better than the rumour has it.
My A7 has the original, allegedly wobbly, stock Sony mount, which has never been exchanged.
philber wrote
Regarding decentering, I wonder whether the mount changes have something to do with it.Here are the two samples, both taken wide open:
https://farm6.staticflickr.com/5785/23845331816_bcfd0da37e_o.jpg
https://farm6.staticflickr.com/5816/23871437425_bf9597bea7_o.jpg
The bottom of Loxia 2/50 is slightly weaker than top probably because of my wobbly original mount. I think the decentering of the 2.8/21mm is pretty obvious and significant here although top left and bottom right look ok to me.
I think you may be looking at a decentered lens in the case of the Loxia 21/2.8. I had a decentered ZF.2 18/3.5, and there were "zones" of sharpnes and unsharpness that didn't correspond to a simple out-of-focus. The good news is that Zeiss in Oberkochen could fix it quickly for me. That lens I had bought used, and it looked like it had never been out of the box. I shot it exclusively with a Sony A7 and a Voigtländer adapter. When it came back everything was top notch. And the ZF.2 18/3.5 is defintely better than the rumour has it.
My A7 has the original, allegedly wobbly, stock Sony mount, which has never been exchanged.
Dec 21, 2015 at 06:36 AM