edwardkaraa wrote:
You are absolutely right. I did try to focus for the extreme corners and they seem to have their optimal sharpness just beyond the 2 meters setting on the focusing scale (probably somewhere around 3-4 m.). However, the field is so surprisingly flat on most of the frame that it would be a pity to lose even a fraction of the sharpness there just to get better corners, which as you see are already great at f/8. Unfortunately I have already deleted the test shots.
I have to say, this stellar performance of the ZS 25 really makes me want that lens now. I had previously thought the Zeiss 25 design was not considered to be a standout in the line.
Tariq Gibran wrote:
I have to say, this stellar performance of the ZS 25 really makes me want that lens now. I had previously thought the Zeiss 25 design was not considered to be a standout in the line.
That's unfortunately the result of us relying too much on lens tests done at or close to MFD. From the few snapshots I took so far I think I can safely say field curvature does not become obvious until 1.5 m. or closer. Even then it can be used creatively as it contributes to producing a stronger 3D effect.
kosmoskatten wrote:
Ed; now that is very impressive corner performance for a wide open, wide angle shot.
Very convincing.
It definitely is. However one should be aware that field curvature becomes more pronounced as focus gets closer. It is also in a U shape (like all Zeiss distagons), which means if you focus at one subject in the foreground, you'll get sharp corners in the background. It is very similar to the ZA 24-70 at 24mm and the field is quite flat in most of the frame (around 80%).
After some further snapshooting, I can see clearly that shooting a central subject at close range with this lens gives beautiful results. Some other subjects would be more difficult to photograph, but I would not use this lens for product shots, or as a serious macro lens. For landscapes or anything beyond 1.5m. distance, it is absolutely stellar, no doubt.
edwardkaraa wrote:
That's unfortunately the result of us relying too much on lens tests done at or close to MFD. From the few snapshots I took so far I think I can safely say field curvature does not become obvious until 1.5 m. or closer. Even then it can be used creatively as it contributes to producing a stronger 3D effect.
Ed; thanks for putting in all the hard work.
All I can contribute with is a supporting hand or two: clap, clap, thanks for doing the preliminary guinea piggin'. I'll stick with piggy-backing until it's time for Piggybanking.
edwardkaraa wrote:
It definitely is. However one should be aware that field curvature becomes more pronounced as focus gets closer. It is also in a U shape (like all Zeiss distagons), which means if you focus at one subject in the foreground, you'll get sharp corners in the background. It is very similar to the ZA 24-70 at 24mm and the field is quite flat in most of the frame (around 80%).
After some further snapshooting, I can see clearly that shooting a central subject at close range with this lens gives beautiful results. Some other subjects would be more difficult to photograph, but I would not use this lens for product shots, or as a serious macro lens. For landscapes or anything beyond 1.5m. distance, it is absolutely stellar, no doubt. ...Show more →
I'm glad we have another who recognizes the values of the ZF/ZS 25/2.8!
And I agree, I would not use the lens for product shot, or a copy lens, or a technical macro lens, but that said, it is GLORIOUS when used close up!.
The new ZA 24/2 looks to improve on the ZS 25/2.8 providing less light falloff at large apertures and a little better corners. But I really would like to see how it performs at closer distances. Other than the limited about of information in the recent Sony press release, do we know any more about the lens' design yet?
Lotusm50 wrote:
The new ZA 24/2 looks to improve on the ZS 25/2.8 providing less light falloff at large apertures and a little better corners. But I really would like to see how it performs at closer distances. Other than the limited about of information in the recent Sony press release, do we know any more about the lens' design yet?
In my opinion, these 2 lenses are close relatives. They both share a stellar performance at infinity (as in Steve's test) and strong field curvature at close distances (as shown in DPR samples, especially the Ivy shot which is very revealing). So it seems Zeiss did a great job in correcting vignetting, even on a wider aperture version, but I have some doubts on how much correction was done on field curvature.
The ZA has 9 elements in 7 groups while surprisingly the 25/2.8 has 10 elements in 8 groups. They both focus very close, 19cm for the ZA versus 17 cm for the 25.
These large DOF landscape lens tests are hard to compare if there is some field curvature going on or not which will help the closer corners. I like the planar lens tests against the side of a large building like how Diglloyd and Le monde de la Photo perform lens tests.
There have been a few threads in the past which compare the ZF/ZE 25/2.8 stopped down to other Zeiss lenses like the CZ 21 and has been shown to be a good performer for landscape and large DOF shooting, especially for the price.
But up close and wide open I don't like the bokeh/drawing style from some of the pictures I have seen as I think it tried to draw too hard the detail in the background and makes it seem hard to separate subject from background as easily as other lenses like the 35/1.4. This is opinion from seeing different shots here as I don't have the lens. Also, close up and wide open causes the most field curvature from this lens which can sometimes help the shot if you can use it to advantage but alot of times I would think it would ruin the shot for me. I prefer more planar.
The ZF/25/2.8 is not a FLE design and does not have the asph element. The ZA 24/2 should kick the ZF 25/2.8's butt at up close, wide open shooting. Even from the crappy dpreview test shots with the ZA 24/2 wide open, I can see it separate the subject from the background better but just not as much as a CZ 35/1.4.
Very interesting to see the microcontrast/contrast difference between ZS 25/2.8 and the ZA 24/2.The difference between Minolta glass and coatings in the ZA vs. the Zeiss with the Schott glass and T* coatings must be causing this substantial difference. This difference adds anotherfactor in the decision between these two lenses.
Doesn't the ZA 24 have T* coatings? Maybe they are somehow different, but it does say T* on the front of the lens...
Also, what is 'Minolta' glass? Does Minolta manufacture glass? Is Minolta even a company anymore? I have no insider knowledge on this, but chances are Sony/Zeiss (whoever is involved with designing the ZA lenses) are ordering their glass from one of the larger glass foundries, one of which is Schott. Though Zeiss certainly might be ordering different types and specifying custom types as well for their own lenses.
I could very well be wrong, but I think only a few manufacturers have exclusive access to specific glass types any more. Canon does with it's fluorite elements; I think they make them in house. Apparently Cosina makes their own. Since Cosina makes the ZS lenses, where is the glass coming from? Schott or in house? Does it even really matter? It's more about the design utilizing the glass types...
Note that I think Zeiss owns a large (majority?) stake in Schott Glass.
kidtexas, I think Wayne was referring perhaps to the effects of the differences in the two lenses on photographic outcomes. I agree with others here that it is highly likely that there is a legacy Minolta effect (or look) in the optical formulation of the ZA series; but glass sourcing - who knows for sure?
Anything CZ does for anyone will surely carry T* coatings...this innovation of the company, introduced back in the day with little fanfare, is a large factor in what they offer to us. It's likely the other German firms, like Schneider and Rodenstock, and B+W all use Schott glass.
As a Sony user getting around to a very wide lens buy, I have to be interested in the 24/2, so another thanks to Ed for this information. I want something with the impact of the better Contax lenses for close, far and in-between focal distances, wide DOF, nature/travel use - and would really appreciate any thoughts or references that compare the new 24mm to the CZ 21/2.8, my other contender, unfortunately burdened by still-high prices and the need for a Leitax remount.
Carl Zeiss was a co founder of Schott glassworks back in 1884. Schott then made their own efforts and ran the company with minor input (if any) from Zeiss for many centuries.
The merger between the companies was a later affair, I have no year to pin that merger to.
In 2004 Schott made a "conversion of its foundation enterprise" (exact phrase excerpt from Schott home page) into Schott AG, with Carl Zeiss AG being the only share holder.
You are right, my bad about the T* coatings. I thought only their own lenses had the T* coatings.
So the glass that Sony uses in their lenses, whether the same as what Minolta used in their lenses prior to Sony buy out or not, must be the difference in the renderings as far as microcontrast/contrast difference between ZA and ZS/ZF/ZE. I think both Zeiss and Cosina lenses use Schott glass along with B&W filters uses it too.
What do you think causes that microcontrast/contrast difference between the two Zeiss designed lenses?
kidtexas wrote:
Doesn't the ZA 24 have T* coatings? Maybe they are somehow different, but it does say T* on the front of the lens...
Also, what is 'Minolta' glass? Does Minolta manufacture glass? Is Minolta even a company anymore? I have no insider knowledge on this, but chances are Sony/Zeiss (whoever is involved with designing the ZA lenses) are ordering their glass from one of the larger glass foundries, one of which is Schott. Though Zeiss certainly might be ordering different types and specifying custom types as well for their own lenses.
I could very well be wrong, but I think only a few manufacturers have exclusive access to specific glass types any more. Canon does with it's fluorite elements; I think they make them in house. Apparently Cosina makes their own. Since Cosina makes the ZS lenses, where is the glass coming from? Schott or in house? Does it even really matter? It's more about the design utilizing the glass types...
Note that I think Zeiss owns a large (majority?) stake in Schott Glass....Show more →
Minolta was famous for making their own glass at one time but I believe that stopped in the mid 90's.
My bet is that the difference in microcontrast between the Sony ZA lenses and the Cosina made, completely Zeiss designed lenses is purely due to design choices. All of these companies have the ability to procure whatever glass types they want from somewhere. It is interesting that Steve has stated this over at the Dyxum forum about the design of the ZA 24:
"Concerning field curvature - I wasn't aware of other Zeiss lenses having the problem at smaller distances, and therefore I didn't test it. Interestingly, the construction seems to be closer to the 1.4/35mm solution (large focusing rear element and fix front wideangle converter), than to the real "distagons". "
So, is the ZA 24 a "real" Distagon or not? What does that even mean beyond an inverted telephoto wide angle design?
wayne seltzer wrote:
There have been a few threads in the past which compare the ZF/ZE 25/2.8 stopped down to other Zeiss lenses like the CZ 21 and has been shown to be a good performer for landscape and large DOF shooting, especially for the price.
But up close and wide open I don't like the bokeh/drawing style from some of the pictures I have seen as I think it tried to draw too hard the detail in the background and makes it seem hard to separate subject from background as easily as other lenses like the 35/1.4. This is opinion from seeing different shots here as I don't have the lens. Also, close up and wide open causes the most field curvature from this lens which can sometimes help the shot if you can use it to advantage but alot of times I would think it would ruin the shot for me. I prefer more planar. ...Show more →
Hi Wayne. I think this is quite subjective, and I don't really agree with your view of this. I prefer the drawing style and bokeh of the ZF 25 close-up and wide-open to the either of the CZ 21mm's. It might not be technically better in terms of the MTF, but the look is captivating to me. It has more seductive character and the subjects just appear more real. I'll accept that this is my subjective opinion, and accept that it is different than your subjective opinion. It is not anything that is universally accepted, but many find it close-up character the lens' most appealing attribute. I'm not found any of my close-up, wide-open images with this lens (which is where I use it most often) to be "ruined" by any aspect of the lens' performance. But as I suggested in my earlier post, I'm not doing copy work with it.
wayne seltzer wrote:
The ZF/25/2.8 is not a FLE design and does not have the asph element. The ZA 24/2 should kick the ZF 25/2.8's butt at up close, wide open shooting. Even from the crappy dpreview test shots with the ZA 24/2 wide open, I can see it separate the subject from the background better but just not as much as a CZ 35/1.4.
Very interesting to see the microcontrast/contrast difference between ZS 25/2.8 and the ZA 24/2.The difference between Minolta glass and coatings in the ZA vs. the Zeiss with the Schott glass and T* coatings must be causing this substantial difference. This difference adds anotherfactor in the decision between these two lenses. ...Show more →
Do we know yet whether the ZA 24mm is a FLE design or has an asph element of any significance? I have found no information on this yet. If you have any info on this. please let us know. I wonder how exotic the ZA 24mm could be, given that it was made to meet a price point (probably similar in price to the ZA 85, which while being a fine performer isn't very exotic). I'm still waiting to see reliable info on this.
It certainly would be interesting to see the ZA 24 and the ZF/ZS 25 side by side to see more clearly the differences in rendering and micro-contrast. I suspect that they are not considerably different in this regard -- the are significant customer expectations in this regard for Zeiss products whether they be made for Sony or anyone else. Both lenses use T* coatings (though it is not clear that the coatings are exactly identical), and I suspect that they both use Schott glass (as Henrik points out, is Zeiss owned) as Zeiss usually designs using their proprietary glass formulations. There is good reason to surmise that these 2 lenses would provide a similar look. Again, a good, thoughtful side-by-side comparison would be able to identify any differences. Anyone have both lenses yet?
Lotusm50 wrote:
Do we know yet whether the ZA 24mm is a FLE design...
I looked for this as well and found nothing thus far stating that the ZA 24 has a floating element, only that it has two aspheric and two Extra-low Dispersion glass elements. Seems like if it is a FLE design, that is something that would have certainly been put in the press release.
I see now that my post was a little confusing. I was comparing the ZS/ZF25/2.8 with the 21/2.8 only in respect to stopped-down landscape shooting. For up close and wide open shooting I was comparing it to the CZ 35/1.4 and thinking the ZA 24/2 will be more like that in respects to separating subject/background.
I just got my copy of the ZE 21/2.8 and have not gotten to shoot much wide-open stuff with it but did notice and was surprised by how much it vignettes. So I have no opinion on the 21 bokeh yet.
I agree the bokeh/drawing style of the 25/2.8 wide open and close is subjective along with whether field curvature bothers you or not. I agree with you that the rendering of the in the focus parts is very real looking.
I looked at the specs in the DPReview review on the ZA 24/2 and see it mentions two asph elements and two ED elements in the design but no mention of floating element design. I thought I saw that somewhere but now can not find it and maybe I confused that with the Nikon and Canon 24/1.4 designs which have two asph elements and ED elements and floating element design. I hope that the 24/2 has a floating element design like the 35/1.4 for good close up performance.
Tariq Gibran wrote:
I looked for this as well and found nothing thus far stating that the ZA 24 has a floating element, only that it has two aspheric and two Extra-low Dispersion glass elements. Seems like if it is a FLE design, that is something that would have certainly been put in the press release.
Except didn't we have a thread a while back about how the Z* 35/2 was considered to have a FLE design which is not mentioned in the Zeiss description?
