Gentlemen, I have just looked through all the examples on Lloyd Chambers' site. Especially looking for good corners at close distance. There was not one example to be found of good corners at any distance. Also, just below one the samples showing poor corner at infinity, he conludes that "The 25/2 Distagon offers stunning results for this type of landscape scene"
alundeb wrote:
Gentlemen, I have just looked through all the examples on Lloyd Chambers' site. Especially looking for good corners at close distance. There was not one example to be found of good corners at any distance. Also, just below one the samples showing poor corner at infinity, he conludes that "The 25/2 Distagon offers stunning results for this type of landscape scene"
Yes, I saw the same. When I subscribed, I always went by what I saw rather than what he wrote.
Doo-bop wrote:
sorry, the EXIF for this images is f2 1/640 35mm ?! you posted the wrong picture by mistake maybe? or maybe I am wrong?
I am using my adapter that i have chipped for my zf 35/2, but Philip_PJ's excellent eye and comment about vignetting and your post of the shutter speed instantly mortified me as I realized for this one shot I probably forgot to stop down to f8 like I wanted and I think this shot made be at f4 or maybe worse yet f2.8. I would like to apologize to everyone for stating the wrong aperture.
Those rocks on right were pretty far away still, I think over 100ft away.
I will post later today my comparisons shot against the church and you can judge the corner performance for yourself and make your own judgements about it.
I still see in my comparison shots of the church that the corner has problems getting sharp till f8 and my ze 21 beats it out for better corners and better performance across the frame. Which is probably not surprising to anyone and you can see this lens is optimized to be very sharp at f2 in the center and pretty far across the frame at close and mid range which is what matters for this type of lens. Colors and lack of CA are excellent and strong point of the lens. There still is a corner issue like the 50MP but a little farther into the frame more and i find 50MP is excellent by 5.6 but I still see a little at f8 with the 25/2.
I guess the question with the lens is if it is possible to photograph something at a uniformly great distance - typical landscape vista distance - where the lens can render across the frame sharpness (center, border and corners) - or is there field curvature which prevents this. The example G. Pierre posted above might be a situation where field curvature and hyper focus distance work together for optimal performance at closer/ mid range distances. At further distances (situation of the landscape vista above), will field curvature prevent across the frame sharpness. I look forward to seeing his results.
I guess the question with the lens is if it is possible to photograph something at a uniformly great distance - typical landscape vista distance - where the lens can render across the frame sharpness (center, border and corners) - or is there field curvature which prevents this.
The Sala Oval del Palau Nacional de Montjuïc answers your question.
Hmm, the 25/2 is even worse than the 50MP in the corners. At least the 50MP sharpens up around f/5.6 or so. I guess it won't be good for architecture or field flatness, more for subjects which are more central. Zeiss has quite a decent collection of such lenses by now
Thanks for these samples, Wayne. I assume you chose optimal focus for the corner?
I don't see any issue with infinity with this lens. I do see excellent performance at close range and infinity, but weak extreme corners combined with curvature of field.
And, the churh must represent magnification in the order of 1:500. If that is not representative of infinity, i don't have a clue
Carsten,
The 25/2 at least doesn't have the mustache distortion of the 21 and if I remember from on line tests the 25/2 doesn't have much distortion so it is not all that bad for architecture. Just don't peek at the corners too much.
wayne seltzer wrote:
Your welcome Alundeb!
No, I chose optimal sharpness with liveview max magnification of the center of the shots.
Sorry, I didn't shoot any shots just trying to optimize for the corners.
BTW the rocks in the crops of my beach shot were farther away than the church is in these shots.
Will show center crops after these left crops which hopefully show I was not to far off trying to get square as possibe with the face of the building and good center focus was obtained.
In these tests the D2.8/21 ZE does not have stellar corners either. More TCA even than the D2/25 (or at least more color fringing).
wayne seltzer wrote:
I still see in my comparison shots of the church that the corner has problems getting sharp till f8 and my ze 21 beats it out for better corners and better performance across the frame. Which is probably not surprising to anyone and you can see this lens is optimized to be very sharp at f2 in the center and pretty far across the frame at close and mid range which is what matters for this type of lens.
Wayne, like all other ZF/ZE lenses the 2/25 is optimized for infinity focus.
How do you know? Do you have test results done at different distances
No, I ordered the lens but was told it could take a few weeks.
I know because that is what Zeiss says when you ask them. It was actually a superfluous question, because the Zeiss lens sheets always show the MTF at the magnification for which the lens is optimized (and in the case of the Makro Planars at additional magnifications).
However, they paid particular attention to the variable air spaces to create a lens that excels over its entire focusing regime, apart from the corners at large apertures. I would not be surprised if PZ and the like go crazy.
Thank you Wayne. I am amazed that the corner of the Z25mm have less CA in your wall pics than with the Z21 even at f8. I mean not a lot but still a visible difference! (head of the angel)
