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Archive 2015Zeiss Unveils the Loxia 21mm f/2.8
p.77 #1Zeiss Unveils the Loxia 21mm f/2.8
stjepan wrote:
Guys, can anybody help with the assessment if the lens is de-centered or not, from the one image? It was carefully focused at infinity, wide open, from 7 stories high.
To me it seems that the lens is problematic in the lower part of the image (left side particularly). Maybe it is that I'm expecting too much from lens at f/2.8 and it just lacks sharpness at the edges. But then the upper edges are just fine in the same image.
Here is the image: https://www.flickr.com/photos/136313585@N04/32459869062/in/dateposted-public/
I'm considering to return the lens to Zeiss for tune up, but would like to be sure...Show more →
Your test is not good enough. See this https://www.fredmiranda.com/forum/topic/1432008/0
Guys, can anybody help with the assessment if the lens is de-centered or not, from the one image? It was carefully focused at infinity, wide open, from 7 stories high.
To me it seems that the lens is problematic in the lower part of the image (left side particularly). Maybe it is that I'm expecting too much from lens at f/2.8 and it just lacks sharpness at the edges. But then the upper edges are just fine in the same image.
Here is the image: https://www.flickr.com/photos/136313585@N04/32459869062/in/dateposted-public/
I'm considering to return the lens to Zeiss for tune up, but would like to be sure...Show more →
Your test is not good enough. See this https://www.fredmiranda.com/forum/topic/1432008/0
Jan 30, 2017 at 04:03 PM
p.77 #2Zeiss Unveils the Loxia 21mm f/2.8
Can you really evaluate anything by taking photos of snow at infinity? I suggest to first clean the lower-left of your monitor 
Jan 30, 2017 at 04:08 PM
p.77 #3Zeiss Unveils the Loxia 21mm f/2.8
stjepan wrote:
Guys, can anybody help with the assessment if the lens is de-centered or not, from the one image?!
Nobody can, sorry. Not from that one image.
To get an initial impression if further investigations are reasonable, you should first of all try a well known simple test method for decentering: Gletscherbruch
Look at 100% crops (!) and compare the 4 corners. If there is significant fall off one or two stops down in one corner, send the lens to Zeiss for a check. If not, your lens is fine.
Guys, can anybody help with the assessment if the lens is de-centered or not, from the one image?!
Nobody can, sorry. Not from that one image.
To get an initial impression if further investigations are reasonable, you should first of all try a well known simple test method for decentering: Gletscherbruch
Look at 100% crops (!) and compare the 4 corners. If there is significant fall off one or two stops down in one corner, send the lens to Zeiss for a check. If not, your lens is fine.
Jan 30, 2017 at 04:13 PM
p.77 #4Zeiss Unveils the Loxia 21mm f/2.8
stjepan wrote:
@ Viramati:
That's exactly the answer I was looking for. To your eyes, do you think my copy is de-centered (link to the photos in the above post)?
I really can't tell from these photos. If I remember rightly mine was out towards the low half of the left hand side. Anyway I would just send it back and get Zeiss to calibrate it as if your not sure about the lens you will never be happy with it
@ Viramati:
That's exactly the answer I was looking for. To your eyes, do you think my copy is de-centered (link to the photos in the above post)?
I really can't tell from these photos. If I remember rightly mine was out towards the low half of the left hand side. Anyway I would just send it back and get Zeiss to calibrate it as if your not sure about the lens you will never be happy with it
Jan 30, 2017 at 04:33 PM
p.77 #5Zeiss Unveils the Loxia 21mm f/2.8
Ok, I understand that it's hard to judge de-centering from the images I provided.
I did conduct however proper testing prior to the shots I posted, so I'm fairly certain that there is slight de-centering present. Here are the crops: https://www.flickr.com/photos/136313585@N04/32583429196/in/dateposted-public/
But I was also looking for opinions on whether the lens is sharp enough at f/2,8 toward the edges. What are others experiences in that regard? To me it seems that the bottom edges are less sharp then the upper edges of the same image: https://www.flickr.com/photos/136313585@N04/32459869062/in/dateposted-public/
And I did focus carefully with those edges in mind. I don't know, maybe I'm expecting too much of the lens. But then again, I owned Samyang 14mm which was sharp throughout the image at f/2,8. And that lens costs only couple hundred bucks, while Zeiss is in a different league all together.
So, to cut the long story short - I'm trying to avoid sending the lens out to Zeiss only for them to tell me that the lens is within specs. I'll probably send it out anyway, as the slight de-centering bothers me. But I always look forward for opinions of fellow photographers when I'm not quite certain and the lens is expensive as this one is.
I did conduct however proper testing prior to the shots I posted, so I'm fairly certain that there is slight de-centering present. Here are the crops: https://www.flickr.com/photos/136313585@N04/32583429196/in/dateposted-public/
But I was also looking for opinions on whether the lens is sharp enough at f/2,8 toward the edges. What are others experiences in that regard? To me it seems that the bottom edges are less sharp then the upper edges of the same image: https://www.flickr.com/photos/136313585@N04/32459869062/in/dateposted-public/
And I did focus carefully with those edges in mind. I don't know, maybe I'm expecting too much of the lens. But then again, I owned Samyang 14mm which was sharp throughout the image at f/2,8. And that lens costs only couple hundred bucks, while Zeiss is in a different league all together.
So, to cut the long story short - I'm trying to avoid sending the lens out to Zeiss only for them to tell me that the lens is within specs. I'll probably send it out anyway, as the slight de-centering bothers me. But I always look forward for opinions of fellow photographers when I'm not quite certain and the lens is expensive as this one is.
Jan 31, 2017 at 01:56 AM
p.77 #6Zeiss Unveils the Loxia 21mm f/2.8
stjepan wrote:
Ok, I understand that it's hard to judge de-centering from the images I provided.
I did conduct however proper testing prior to the shots I posted, so I'm fairly certain that there is slight de-centering present. Here are the crops: https://www.flickr.com/photos/136313585@N04/32583429196/in/dateposted-public/
But I was also looking for opinions on whether the lens is sharp enough at f/2,8 toward the edges. What are others experiences in that regard? To me it seems that the bottom edges are less sharp then the upper edges of the same image: https://www.flickr.com/photos/136313585@N04/32459869062/in/dateposted-public/
And I did focus carefully with those edges in mind. I don't know, maybe I'm...Show more →
Well seeing your in Croatia I presume the lens will go back to Zeiss in Germany. I sent mine there through my dealer and they included a few words saying what I thought was wrong with it. Zeiss did not question my finding and just got on with it an adjusted the lens. I always send things back through my dealer as I think it is a better way of dealing with it and if there are any questions by the service department they can handle it and probably have a bit more authority while doing so
Ok, I understand that it's hard to judge de-centering from the images I provided.
I did conduct however proper testing prior to the shots I posted, so I'm fairly certain that there is slight de-centering present. Here are the crops: https://www.flickr.com/photos/136313585@N04/32583429196/in/dateposted-public/
But I was also looking for opinions on whether the lens is sharp enough at f/2,8 toward the edges. What are others experiences in that regard? To me it seems that the bottom edges are less sharp then the upper edges of the same image: https://www.flickr.com/photos/136313585@N04/32459869062/in/dateposted-public/
And I did focus carefully with those edges in mind. I don't know, maybe I'm...Show more →
Well seeing your in Croatia I presume the lens will go back to Zeiss in Germany. I sent mine there through my dealer and they included a few words saying what I thought was wrong with it. Zeiss did not question my finding and just got on with it an adjusted the lens. I always send things back through my dealer as I think it is a better way of dealing with it and if there are any questions by the service department they can handle it and probably have a bit more authority while doing so
Jan 31, 2017 at 03:12 AM
p.77 #7Zeiss Unveils the Loxia 21mm f/2.8
A quick update. I have since contacted Zeiss directly through web form. Received the first response within couple of hours (remarkable). They asked to see one picture best presenting the problem, full size, exif data and info about the focusing distance. Sent it yesterday evening, now waiting on their findings.
I'm curious as to what their response will be. Hopefully we'll see eye to eye.
I'm curious as to what their response will be. Hopefully we'll see eye to eye.
Feb 01, 2017 at 04:35 AM
p.77 #8Zeiss Unveils the Loxia 21mm f/2.8
Got my Loxia 21 today. Having done Freds centering test it seems well centered. However im having issues with focus. Ive read on here that for landscape apertures its best to hit the hard stop and back it off a tad. When I take two test shots (one on the hard stop and one backed off a tad) and compare in photoshop the backed off image is much sharper in the foreground but things on the horizon go softer.
Maybe im backing it off too much? How much is "a tad"? Are we talking a couple of millimetres or basically just the slightest of movements away from the hard stop?
Thanks
Maybe im backing it off too much? How much is "a tad"? Are we talking a couple of millimetres or basically just the slightest of movements away from the hard stop?
Thanks
Feb 02, 2017 at 10:59 AM
p.77 #9Zeiss Unveils the Loxia 21mm f/2.8
Sounds like you're backing off too much.
Use the EVF and the focus magnification. That's what it's there for. I wouldn't go based on how many millimeters someone says it is with their lens.
Use the EVF and the focus magnification. That's what it's there for.
I wouldn't go based on how many millimeters someone says it is with their lens. Feb 02, 2017 at 11:02 AM
p.77 #10Zeiss Unveils the Loxia 21mm f/2.8
xpfloyd wrote:
Got my Loxia 21 today. Having done Freds centering test it seems well centered. However im having issues with focus. Ive read on here that for landscape apertures its best to hit the hard stop and back it off a tad. When I take two test shots (one on the hard stop and one backed off a tad) and compare in photoshop the backed off image is much sharper in the foreground but things on the horizon go softer.
Maybe im backing it off too much? How much is "a tad"? Are we talking a couple of millimetres or basically...Show more →
Yes, I agree. I think you are backing off too much. When I focus the my L21, I set it to almost the hard stop. I only back off a "tiny" bit because I care about my center. I got so used to it, I don't even check focus anymore. (Looking at the lens, it still looks as though it's almost at the hard stop).
If you want to use the camera magnification instead, the easiest way to focus the L21 is to aim at the mid-field area.
The L21 has moderate field curvature so you will never get razor sharp center AND extreme corners at the same time when shooting at wider apertures. (Stopping down to f/5.6 and smaller flattens the field quite a bit but it's still noticeable)
If you go all the way to the hard stop, the extreme corners will look best but it will cost you some center resolution. (Inwards field curvature)
Got my Loxia 21 today. Having done Freds centering test it seems well centered. However im having issues with focus. Ive read on here that for landscape apertures its best to hit the hard stop and back it off a tad. When I take two test shots (one on the hard stop and one backed off a tad) and compare in photoshop the backed off image is much sharper in the foreground but things on the horizon go softer.
Maybe im backing it off too much? How much is "a tad"? Are we talking a couple of millimetres or basically...Show more →
Yes, I agree. I think you are backing off too much. When I focus the my L21, I set it to almost the hard stop. I only back off a "tiny" bit because I care about my center. I got so used to it, I don't even check focus anymore. (Looking at the lens, it still looks as though it's almost at the hard stop).
If you want to use the camera magnification instead, the easiest way to focus the L21 is to aim at the mid-field area.
The L21 has moderate field curvature so you will never get razor sharp center AND extreme corners at the same time when shooting at wider apertures. (Stopping down to f/5.6 and smaller flattens the field quite a bit but it's still noticeable)
If you go all the way to the hard stop, the extreme corners will look best but it will cost you some center resolution. (Inwards field curvature)
Feb 02, 2017 at 11:25 AM
p.77 #11Zeiss Unveils the Loxia 21mm f/2.8
Thanks Fred, I was backing off to the edge of the infinity symbol so sounds like too much. It got dark 10 mins after I finished the decentering test so will have to wait until tomorrow to test it more but at least I know what I'm aiming for now.
Sorry if this is a stupid question but when you say focus at the mid field area do you mean half way from the horizon to where I'm standing or do you mean half way between the centre and the corner of the frame at something on the horizon?
Sorry if this is a stupid question but when you say focus at the mid field area do you mean half way from the horizon to where I'm standing or do you mean half way between the centre and the corner of the frame at something on the horizon?
Feb 02, 2017 at 11:42 AM
p.77 #12Zeiss Unveils the Loxia 21mm f/2.8
xpfloyd wrote:
Thanks Fred, I was backing off to the edge of the infinity symbol so sounds like too much. It got dark 10 mins after I finished the decentering test so will have to wait until tomorrow to test it more but at least I know what I'm aiming for now.
Yes, that's way too much with my copy.
or do you mean half way between the centre and the corner of the frame at something on the horizon?
This one. ^
Thanks Fred, I was backing off to the edge of the infinity symbol so sounds like too much. It got dark 10 mins after I finished the decentering test so will have to wait until tomorrow to test it more but at least I know what I'm aiming for now.
Yes, that's way too much with my copy.
or do you mean half way between the centre and the corner of the frame at something on the horizon?
This one. ^
Feb 02, 2017 at 12:09 PM
p.77 #13Zeiss Unveils the Loxia 21mm f/2.8
Thanks for clarifying, I was over thinking that one there
Feb 02, 2017 at 12:12 PM
p.77 #14Zeiss Unveils the Loxia 21mm f/2.8
With my copy, hard stop is at middle of infinity symbol. If I focus at the edge of infinity symbol (before hard stop), subject at infinity centre will be sharpest but if I focus at halfway between hard stop and the edge of infinity symbol, subject at infinity edge will be sharpest. Focusing at hard stop will cause all infinity subject blur, both edge and centre.
Feb 03, 2017 at 03:35 AM
p.77 #15Zeiss Unveils the Loxia 21mm f/2.8
Been enjoying mine, must get out and use it more
Feb 05, 2017 at 05:42 PM
p.77 #16Zeiss Unveils the Loxia 21mm f/2.8
Hello Fred,
you mentioned you tried loxia 21mm with lee seven5. Did you also tried the polarizer? I mean the external polarizer that comes with an extra support and should be mounted in top of the holder.
Regards and thank you in advance
you mentioned you tried loxia 21mm with lee seven5. Did you also tried the polarizer? I mean the external polarizer that comes with an extra support and should be mounted in top of the holder.
Regards and thank you in advance
Apr 08, 2018 at 05:57 AM
p.77 #17Zeiss Unveils the Loxia 21mm f/2.8
hanay78 wrote:
Hello Fred,
you mentioned you tried loxia 21mm with lee seven5. Did you also tried the polarizer? I mean the external polarizer that comes with an extra support and should be mounted in top of the holder.
Regards and thank you in advance
I have used the Loxia 21 extensively with the LEE Seven5 kit, including the polarizer that mounts to the filter holder. It works perfectly.
Hello Fred,
you mentioned you tried loxia 21mm with lee seven5. Did you also tried the polarizer? I mean the external polarizer that comes with an extra support and should be mounted in top of the holder.
Regards and thank you in advance
I have used the Loxia 21 extensively with the LEE Seven5 kit, including the polarizer that mounts to the filter holder. It works perfectly.
Apr 08, 2018 at 06:31 AM
p.77 #18Zeiss Unveils the Loxia 21mm f/2.8
Thanks! No vigneting at all them?
Apr 08, 2018 at 07:49 AM
p.77 #19Zeiss Unveils the Loxia 21mm f/2.8
The polarizer did not add any vignetting that I have noticed. The Loxia 21 has a bit of natural vignetting at wider apertures, but nothing close to being problematic.
Apr 08, 2018 at 07:51 AM