wickerprints wrote:
As for "who cares," and who is leaving things alone, it's not the Canon users who are making claims that their lenses are producing some magical effect and asking everyone else to believe it.
As a Canon user, I have often made claims about the magical effects produced by the 85L II and the 135L lenses if used appropriately. I have, however, never asked anyone to believe these claims. I want my delusions to be my own :-)
saaketham wrote:
There was a recent study which found that shopping Apple is almost a religious experience. And I agree - I'm strongly biased towards minimalistic design and no-popups telling me my PC is about to be hacked by Chinese unless I immediately spend $50 on an anti-(virus/spyware/malware) app. I love Apple products - except I don't buy some of the overpriced ones like the MBP or Mac Pro. I'm guessing Zeiss induces the same effect on people?
Apple vs. Microsoft is more like comparing Canon vs. Nikon, rather than Canon vs. Zeiss, because while there are tendencies toward brand loyalty in all instances, the issue with Canon vs. Zeiss that is not common to the other comparisons is that the claims of Zeiss being better are often unsupported in any objective sense. By contrast, the other comparisons are more about picking apart various real, objective differences and the debate stems from people making different value judgments about which aspects are more important.
To illustrate, an objective difference between the 100L and the 100 MP is that the former has AF; the latter does not. Another is that the former only opens to f/2.8; the latter opens to f/2. In this regard, the comparisons are like saying Mac OS has a UNIX-based command line, whereas Windows has a DOS-based command line.
However, a subjective difference is the claim that the 100L doesn't achieve a "3D look" as easily as the 100 MP. The side-by-side comparisons to date have not demonstrated this assertion. Apple vs. Microsoft debates are largely devoid of such types of statements or reasoning. Instead, they argue over whether HFS+ is "better" than NTFS, and why; or why it is better to have a removable battery or not. The differences are real, but the value of their consequences are the point of discussion. That is largely not the case with Canon vs. Zeiss.
More appropriate analogies have already been given, such as wine tasting, and audiophile debates.
I would like to point out that comparing the performance of two macro(ish) lenses by looking at samples at infinity focus seems quite silly to me.
Here are some of my views on things related to the thread:
The so-called 3D effect can be caused by several different factors and/or combination of factors, some of which have been listed in this thread. One of these factors is microcontrast. Microcontrast is a lens characteristic, namely high lp/mm values at very low frequencies. This is quantifiable.
The significance of microcontrast in creating a "3D effect" can be debated(and has been, among other places in this thread), but at least it has a factual, quantifiable effect on the image(more fine detail, or the appearance of more fine detail).
Now before any of you start a long-winded rant in response I would like you to read through my post, see what I actually stated, specify exactly what you disagree with and take a deep breath.
RZetter wrote:
Wow, this really turned into a circle-jerk.
Not sure what group masturbation has to do with the discussion in thread, but whatever...
I would like to point out that comparing the performance of two macro(ish) lenses by looking at samples at infinity focus seems quite silly to me.
To you perhaps. However, the point that most Zeiss fans are quick to raise in any comparison is how the Zeiss outperforms the Canon at longer focus distance (and its consistency as focus distances changes). This is usually brought up whenever the 100L's advantage of being able to do 1:1 is raised. Hence, if the claim is that the Zeiss' strength is at varying focus distance, then it stands to reason that claim should be put to test.
Here are some of my views on things related to the thread:
The so-called 3D effect can be caused by several different factors and/or combination of factors, some of which have been listed in this thread. One of these factors is microcontrast. Microcontrast is a lens characteristic, namely high lp/mm values at very low frequencies. This is quantifiable.
The significance of microcontrast in creating a "3D effect" can be debated(and has been, among other places in this thread), but at least it has a factual, quantifiable effect on the image(more fine detail, or the appearance of more fine detail).
Now before any of you start a long-winded rant in response I would like you to read through my post, see what I actually stated, specify exactly what you disagree with and take a deep breath.
Just to clarify. So the 3D effect is created (although with much debate) by high microcontrast which by your description I would infer means high modulation of contrast at low spatial frequencies. Great, so what spatial frequencies? 10 lp/mm? 20?
We have some data, Canon's 100L MTF chart has data for 10 lp/mm and 30 lp/mm wide open and stopped down:
Looking at the two graphs for low spatial frequency (in the Canon graph thats the thick lines, in the Zeiss its the first set at the top I believe), what does it tell you? Not being facetious, just want to know what you see.
Then we'll spend another 15 pages making our eyes bleed by reading MTF graphs and eventually someone will once again suggest posting images to spot the comparison.
Mirek Elsner wrote:
It should not be surprising that it is most often discussed by people who actually use these lenses.
As I wrote earlier:
"Several powerful forces are at work here. In the lineage of the "emperor's new clothes," few want to admit that they don't see the difference that everyone else sees, much less the difference that the really smart people claim to see. Sometimes though, especially in areas like wine and sound equipment and photographic equipment, where a certain percentage of people use the field as a way to demonstrate their superiority by acquiring "the best stuff," certain people are really, really invested in having the best stuff. And another issue is that once one invests (mentally and financially) in "the best," it is very, very difficult to see rationally when owning the best makes no discernible difference in the final product. Making things more complex is the fact that the quality of the stuff does matter - though not quite in the way that these folks imagine."
Note: Canon's own MTF plots are often fairly useless. Unlike Zeiss (who publish MTFs measured from actual production lenses), Canon's MTFs are only "theoretical" calculations that even ignore the harder parts of theory to calculate (e.g. diffraction effects). Many of Canon's MTFs (like the one shown for the 100L) should be considered embarrassing because they are physically impossible --- at f8, a theoretically perfect lens (diffraction limited) cannot have as high MTF curves (at least towards the center) as Canon shows. Other companies (e.g. Leica) also use "calculated" MTFs, but they at least include relevant optical effects in their calculations. To get useful MTFs for Canon, you will need to look at some third-party lens tester (like Photodo) who actually measure real lens MTFs in a repeatable fashion.
The MTF curves can't be directly compared, since Zeiss curves are based on measured (achieved) results, while Canon's are calculated based on perfect construction and, importantly, a world without diffraction. Perhaps we can all agree that Canon and Zeiss lenses are equally subject to diffraction.
What you can estimate from the curves, though, is that the Zeiss has less lateral chromatic aberration than the Canon. This is also clear from the TDP results — flawed as they are — and sample photos I've seen elsewhere, not to mention most other reviews such as the one at Photozone.de, etc.
In fact, I'd argue that lateral chromatic aberration is the most significant difference between these lenses at small apertures. If I had the two lenses I'd go and shoot a high-contrast edge in the corner of the frame at f/8 to put this matter to rest. For example, shoot a roof against an overcast sky, with the roofline in a tangential orientation. Full-resolution photos of this kind will reveal the clear superiority of the Zeiss.
The criticisms of Canon's MTF graphs are well deserved. However, Photozone's are fairly incomplete as well. What they plot (i.e. the lp/ph at MTF50) is sufficient to describe what can most aptly be called 'sharpness'. I think what we'd need to see are graphs at various spatial resolutions.
I took a look at photodo and found the site be underwhelming. They have one review of the 100L and this is the graph they post:
[image removed due to busted link]
which is no better than Photozone's data.
I did take a peek at DXOMark and they seem to have the best data I've found yet:
Scoot over to the 'Resolution' tab and click on MTF.
They allow you to compare curves with lp/mm plotted against MTF. Unfortunately, you need to produce separate graphs for the center vs. 1/3 in vs. corners. It also looks like they've separated the data for each of the channels so make sure you through all of them (there's some wild stuff in blue).
I'll refrain from posting my own observations as to not bias folks.
I should add that even DXO's data is presumably for some fixed focus distance (since they don't offer that as a parameter).
The problem with doing such quantitative data measurements is that the number of dimensions you have is high which makes all the various combinations just explode. Its why I usually prefer two images taken side by side, seems simpler to me...
charlesk wrote:
I've never seen a single truly scientific test to show that people can pick out images from very similar pairs taken by Zeiss and non-Zeiss lenses.
This is a blind test by members of the FM Alt forum. This looks like a very statistically significant result to me. Once you know what to look for, the differences are not too hard to find in the crops.
Critics may complain that the tester did not always use the comparable L lens, as he used what he had on hand. Still it clearly addresses your request for a rigorous test comparing images from a Zeiss lens Vs images from a non-Zeiss lenses in a blind test.
Mike K
SKumar25 wrote:
Aravind, will you be keeping your zeiss based on your experiences?
Yes, I likely will but my use case for the lens is perhaps different from others. My main use for the ZE 100 MP is landscapes, shot on a tripod. So the things it does well namely:
1. Sharp across the field when stopped down and at a variety of focus distances
2. Long throw MF ring makes precise focusing easy, which I find I need to get the plane of focus precisely right to have everything I want within the depth of field
3. Compact storage. This is trivial at first sight but I find the Zeiss easier to pack into my compact landscape kit
are beneficial to me, although not critical to my photography. I see the ZE 100 as a luxury that I could give up but it makes my photography fun for me. In the end thats whats important and I can afford it so it ends up being pretty simple.
This is a blind test by members of the FM Alt forum. This looks like a very statistically significant result to me. Once you know what to look for, the differences are not too hard to find in the crops.
Critics may complain that the tester did not always use the comparable L lens, as he used what he had on hand. Still it clearly addresses your request for a rigorous test comparing images from a Zeiss lens Vs images from a non-Zeiss lenses in a blind test.
Mike K
Fascinating. The only comparison in that series that is at all relevant to this thread is "D" the comparison between the Zeiss 100 MP and the Canon 100 Macro.
The difference in per pixel sharpness is great, so great that I have to wonder if its real. It looks like the Zeiss image has had some kind of post resizing sharpening applied and the Canon one hasn't.
Regardless its not something I've been able to reproduce try as I might.
A similar shoot with the 50 L would have been equally attractive to my eye, but the look would have been different. The artistic outcome would be different.
Can I measure this, no. Can I subjectively compare, yes. If you don't see this, that is fine.
To compare a few side by side samples and imply people who state this have some agenda is crazyiness to me.
Thedigitalbean: I suspect mpmendenhall was referring to the old photodo.com website, which measured MTF on a Zeiss-made MTF tester. This is a very different kettle of fish from the DSLR-based MTF testing done on countless sites today, and is a body of work that remains very useful today. The old photodo.com website is viewable via the Wayback Machine on archive.org, though of course it doesn't include recent lenses.
If you have access to the lenses discussed in this thread, it would be very useful to do a test for lateral chromatic aberration at infinity, as I mentioned in my last post. Since the Zeiss is clearly better corrected for this than the Canon, it would be easy to show the difference in real photos, albeit contrived real photos in this case. The alleged micro-contrast advantage of the Zeiss at some apertures is perhaps a more subtle thing, though on the evidence I've seen it probably exists. On the other hand, the Canon clearly has less false colour in the out-of-focus regions, and this aberration is in extreme cases seen in small prints or web images. Differences would probably also be clear in flare handling at various apertures in various contre-jour situations, although testing this methodically would take great effort.
thedigitalbean wrote:
Yes, I likely will but my use case for the lens is perhaps different from others. My main use for the ZE 100 MP is landscapes, shot on a tripod. So the things it does well namely:
1. Sharp across the field when stopped down and at a variety of focus distances
2. Long throw MF ring makes precise focusing easy, which I find I need to get the plane of focus precisely right to have everything I want within the depth of field
3. Compact storage. This is trivial at first sight but I find the Zeiss easier to pack into my compact landscape kit
are beneficial to me, although not critical to my photography. I see the ZE 100 as a luxury that I could give up but it makes my photography fun for me. In the end thats whats important and I can afford it so it ends up being pretty simple....Show more →
This is pretty much how I sum it up for me. I have much more fun shooting the Zeiss glass but, I love my 16-35 II and can't imagine ever giving that lens up. At any rate, the 100 is my favorite Zeiss lens. You mentioned compact storage. This is huge. Because of the small size of these lenses I can carry the 21, 35, 50, 16-35 and 24-105 in my Flipside 400 while the 5D2 is around my neck with the 100 on.
What The ... Fish! I turn my back for most of today (busy day at the office) and I fell 5 pages behind on this thread! I don't know if I should laugh or cry but I will stick some popcorn in my microwave tonight and bring myself up to speed.
A similar shoot with the 50 L would have been equally attractive to my eye, but the look would have been different. The artistic outcome would be different.
Can I measure this, no. Can I subjectively compare, yes. If you don't see this, that is fine.
To compare a few side by side samples and imply people who state this have some agenda is crazyiness to me.
You just don't get it, do you? We are NOT comparing other pairs of lenses here. We are saying, show everybody a situation in which the 100 MP will take an image with this desired "look" but the 100L, under the same conditions, will not.
thedigitalbean wrote:
The difference in per pixel sharpness is great....
Can you define "per pixel sharpness?" I do not understand how a pixel can have "sharpness."
SKumar25 wrote:
A similar shoot with the 50 L would have been equally attractive to my eye, but the look would have been different. The artistic outcome would be different.
Wait. They would be "equally attractive to [your] eye" but one would look better than the other? Isn't that sort of like "they both taste just as good but one tastes better?"
