I think your wall test looks pretty good. 2.8 Wont match 5.6 but it's on track. No asymmetrical issues as its even on both sides. Just add a touch of base sharpening and I think you are better than the first copy. Your also shooting with overcast skies so images tend to appear less sharp. Try again with sun out and watch it pop.
Anyone own both this and the basis 18mm? I'm torn on which to go for. I don't have anything wider than 24mm, so I'm debating over whether 21mm is wide enough for a "single lens" wa solution.
Just received my Loxia 21 and am trying to do the decentering test.
However it seems there is something wrong with my copy?
I tried to MF (with 10x zoom assist) on the far trees on the top left corner to my best ability, the focus ring was turned all the way to infinity and back a lil.
However if you look at the image below the trees that are much closer are at sharp focus?
I did a similar test at f8 and all corners seem to be sharp enough. But I thought the test is supposed to be done @ f2.8
So what does it mean and how do you interpret this?
Can I use a tripod to focus on something dead center at f5.6 or f8, when done rotate the lens on the head (as close to nodal point as possible) to place the subject I initiated focused near the extreme left edge or the frame, take a shot, rotate again to place the same subject on the right edge of the frame.
This way I have a control (center), and two shots from each sides. I know the edge shots will be blurry/less IQ, due to lack of DOF or field curvature. But the point is not to match the center one, it is to determine if the two edge shots are the same in blurriness.
8is the above a valid testing procedure? I purposely use smaller Aperture to minimize the difference, because smaller Aperture should provide an advantage. So I can determine how compromised/decemtered even in advantageous Aperture.
Please share your thoughts if you think this test procedure can be refined.
Quick question, for those with experience. I've just purchased the Loxia 21 and it's a sweet lens, sharp and beautiful all around, but starting from f/5,6, at least for my copy. Prior to that it's still fine for 95% of the frame, but the edges do suffer (especially bottom ones). It's nothing dramatic, but giving the praise this lens gets, I wonder if my copy is decentered. I'll try to post some images later to get some experienced insight.
But in the meantime let's presume that I do have a decentered lens. If I was to send it to Zeiss Oberkochen for a tune up, what would it cost me? The lens is new and under warranty.
Thanks for the help, it is much appreciated.
I guess it wasn't a quick question, after all. Huh
GMPhotography wrote:
New than I would first test it than exchange it. I would not send it in myself if I can exchange it first. Too much time goes by and hassle
I understand that, but let's say I'd prefer the option to have it checked by Zeiss. I could also get another suboptimal lens from the dealer, and thus have to send it back again and so forth. This also costs money. It is unlikely to happen twice with Zeiss I know, but still.
If this is an expensive option or extensively time consuming, I would reconsider, of course.
If you get a second one and it looks good in tests than why have Zeiss check it. A bad lens is a bad lens, certainly your a fine judge of that. It's your money and time but I know myself I would not screw around with a marginal copy and return it until I feel good about it. From my seat Zeiss is no better at checking my testing than myself.
GMPhotography wrote:
If you get a second one and it looks good in tests than why have Zeiss check it. A bad lens is a bad lens, certainly your a fine judge of that. It's your money and time but I know myself I would not screw around with a marginal copy and return it until I feel good about it. From my seat Zeiss is no better at checking my testing than myself.
I agree. As long as your test methodology is flawless, you should only trust your own eyes.
I agree with both of you. But I was under the impression that Zeiss can fix the lens, if decentered. Not check for flaws, I'm capable of that myself. The reason I'm asking is that I'm tired of buying/sending lenses back if they are bad copies. Especially when I have paid multiple times for shipping via second day delivery. It doesn't come cheap here in Europe.
I don't know if this is just my luck, but it seems quite often with lenses these days. Or it simply went unnoticed on fewer mpix bodies of the past. Or I'm just nitpicking by nature. Sure I would use the lens for landscapes at f/8 mostly where the lens performs well, but still.
If you happen to find my tests or Fred's even at 2.8 in the corners is not bad at all. It should be that good there. No question it hits it mark I think at 5.6 but even wider it's not bad at all.
stjepan wrote:
I agree with both of you. But I was under the impression that Zeiss can fix the lens, if decentered. Not check for flaws, I'm capable of that myself. The reason I'm asking is that I'm tired of buying/sending lenses back if they are bad copies. Especially when I have paid multiple times for shipping via second day delivery. It doesn't come cheap here in Europe.
I don't know if this is just my luck, but it seems quite often with lenses these days. Or it simply went unnoticed on fewer mpix bodies of the past. Or I'm just nitpicking by nature. Sure I would use the lens for landscapes at f/8 mostly where the lens performs well, but still....Show more →
When I got my loxia 21 it was slightly de-centerd and as I really didn't want to go through the unpredictable hassle of trying another copy my dealer sent it back to Zeiss in Germany and 3 weeks later and I got back a perfectly calibrated copy and none of the process cost me a penny as it was covered by the warranty
My concern is mainly with the performance at the lower left hand part of the image. The lens seems to be at its weakest there (both distant and close subjects, more so with distant). At least it looks that way to me.
What do you think guys? Would you consider the performance in line with the norm for this lens wide open? Or should it be better?
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.