Well if you have two lenses with following characteristics:
- same focal length
- same maximum f
- similar build quality and functionality
- covers same sensor size
where lens A has objectively better MTF charts than lens B, than I expect lens A to be bigger. But that is only me.
Makes sense, extensive corrections generally require more lens elements. However, it isn't *necessarily* so. Leica's genius is partly in making highly corrected lenses, but also making them compact.
Of course, that is why I used "expected", which doesn't equal "necessary". Leica definitely knows how to make compact lenses. In fact it is my opinion, that they don't even WANT to produce anything big, because it just doesn't go well with their philosophy and with what their clients expect from them. Look at 16-18-21, a lens that nobody would cry if it was just a bit bigger, but they instead kept it small by using f4. It's not SLR lens, but still I believe that staying small is more important to them than it is to Zeiss.
trdonja wrote:
Well if you have two lenses with following characteristics:
- same focal length
- same maximum f
- similar build quality and functionality
- covers same sensor size
where lens A has objectively better MTF charts than lens B, than I expect lens A to be bigger. But that is only me.
But the unknowns are number of elements, the type of elements, and the type of glass employed. These will impact the the size and quality, but not necessarily in a positive linear relationship. Without controlling for these unknowns -- i.e., you cant tell them from an MTF (even if you might be able to guess at what might be present in the design) -- a strict relationship between size and performance does not hold, and you can not "expect" the better performing lens to be a bigger lens.
Yes, the question the glass material used in the lens should not be underestimated. For instance the rather special and very expensive ($10,000) and for a rangefinder lens very large Leica 50/0.95 Noctilux has several lens elements made of a glass that has to cool for six months. Using exotic glass can become very expensive and while Zeiss with its ZE/ZF line definitely has its sights on the premium lens market they still tend to try to keep prices reasonable.
It's not unreasonable to imagine that they could have probably made it more compact with the same optical performance by using other types of glass but with a much higher production price.
Lotusm50 wrote:
But the unknowns are number of elements, the type of elements, and the type of glass employed. These will impact the the size and quality, but not necessarily in a positive linear relationship. Without controlling for these unknowns -- i.e., you cant tell them from an MTF (even if you might be able to guess at what might be present in the design) -- a strict relationship between size and performance does not hold, and you can not "expect" the better performing lens to be a bigger lens.
What is your definition of "expect" then? Most of the definitions require probability to be only above 50% but I will go to 67%, just to make it more interesting and easier to test. For every example when my statement is not true I will give you two examples where it is true. So I stand by my "expectation" but I definitely understand your valid points as well. Nothing is certain and I don't claim it to be.
Of course such test would hit subjective obstacles sooner or later so maybe not the best idea. But in case of those two MTF charts I would estimate at least 90% probability of Zeiss lens to be considerably bigger.
Trdonja, the two parameters that most strongly correlate to lens size are maximum aperture and focal length. Given that you can find many examples that go against that rudimentary relation, I would definitely not bet any money on resolving power (i.e. MTF curves) being proportional to lens size.
"Expect": "To consider likely or certain", "To look forward to the probable occurrence or appearance of" ("probable" = "likely to be true"). A degree of confidence is not part of the definition.
Let's not mix this up with the technical statistical term "expectation". Even statistically you can not formulate an expectation in this case, becuase the probabilities of all events/outcomes are not known. Key variables (which I outlined above) are unknown so you just don't know. This is "uncertainty", not expectations based on known probabilities of known outcomes.
denoir wrote:
It's not the 35/2 people are comparing it to but the legendary Zeiss 35/1.4 Distagon, i.e the previous version of the lens. It's one of the most valued primes around here and very likely the most appreciated 35mm lens. So it's perfectly natural that people are surprised by the significant difference in physical dimensions and weight of the new one.
No, it's because you made a couple of inaccurate statements that people have been correcting you. I'm sure most people here agree that image quality trumps size/weight issues at least within reason. The MTF charts look good but apart from that we don't have much to go on yet. The samples that we've seen so far have not been adequate to give a good idea of the general character and performance of the lens. So we discuss what we know about it - i.e that it's unusually large and heavy.
It's nothing, you should wait for when the images come in when there will be a widespread condemnation of the new one for not being like the old one. It's a law of nature. ...Show more →
Ok, let's see what statement I did in this thread before it started then. Tell me which one of these that was inaccurate and needed to be corrected then. These two where the only I made before it started
""Image quality & Build quality are a lot more important than weight & size""
""Where in EU do I buy this lens for a good price? Just over 1500 euro is the lowest I have seen""
And you still not get it I'm not saying they should compare it (IQ or speed) against the Zeiss 35/2. I'm saying that when that lens weight 530 gr. The new lens have to be a lot more heavy. All the new Zeiss lenses has the same build and it's rather easy to compare weight between those
Andi Dietrich wrote:
among other, weight is the price for better corner sharpness. we have complained about this for years, here you go.
I've never heard a Zeiss 35/1.4 user "complain" about corner sharpness. I find it to be very acceptable on my late Rollei version wide open or stopped down. As a landsscape shooter I am very picky about any lens I use for that purpose. I am very happy to use a current Zeiss 35/1.4 for it.
If I want better corner sharpness I could bring along my Oly MC 35/2.8 shift, still have less weight combined than the new version alone - and have shift capability.
We all know it's not all about sharpness. My Rollei/Zeiss draws very distinctively even when stopped down.
Lotusm50 wrote:
"Expect": "To consider likely or certain", "To look forward to the probable occurrence or appearance of" ("probable" = "likely to be true"). A degree of confidence is not part of the definition.
Let's not mix this up with the technical statistical term "expectation". Even statistically you can not formulate an expectation in this case, becuase the probabilities of all events/outcomes are not known. Key variables (which I outlined above) are unknown so you just don't know. This is "uncertainty", not expectations based on known probabilities of known outcomes.
We will just have to agree to disagree, on both linguistic and statistical point of view. It would get too much off topic I believe.
trdonja wrote:
Well if you have two lenses with following characteristics:
- same focal length
- same maximum f
- similar build quality and functionality
- covers same sensor size
where lens A has objectively better MTF charts than lens B, than I expect lens A to be bigger. But that is only me.
Sven Jeppesen wrote:
And you still not get it I'm not saying they should compare it (IQ or speed) against the Zeiss 35/2. I'm saying that when that lens weight 530 gr. The new lens have to be a lot more heavy. All the new Zeiss lenses has the same build and it's rather easy to compare weight between those.
I agree that it is more logical to compare it to the Z* 35/2 because that one gives a better indication of the kind of bulk which Zeiss allows in their current designs.
AhamB wrote:
I agree that it is more logical to compare it to the Z* 35/2 because that one gives a better indication of the kind of bulk which Zeiss allows in their current designs.
Yes I agree. The designs of most of the new Zeiss lenses are very heavy and large. So for the people that think small size and low weight is very important there are other options
My first reaction to the size as reported by numbers was .."WHAT??!!?"
Then i simmered down and realized that the measurements were all wrong. No way the mockup I saw was that big. Then I read the ENTIRE SENTENCE in the Zeiss data flyer, and my eyes stuck on the phrase:
-"....including end caps...."
Ah......
The real length of the lens is ~96mm. Not 122mm, as the initial report says. Still freaking huge for a DSLR 35mm lens (but in filmatic lenses so tiny that you'd be afraid that it should fly away in the breeze if shooting outdoors...)
I made this comparison a bit quickly, but i think I got the individual scales right. The numbers are correct in any way. http://ezpicshare.com/images/ze3514-1295489580.jpg
My first impression is that it was HUGE and HEAVY. Then I now remember I got to try a pre-production copy back in October.
It was definately heavy and kinda big. In fact it's heavier than any lens I currently own. But I don't think it would affect any decision to buy it or not.
It's just any time you'd bring it along, you know it'll be big and heavy, you know it'll be inconvenient and annoying, might weigh down your camera bag, make your shoulders or arm sore but you'll just live with it.
Andi Dietrich wrote:
among other, weight is the price for better corner sharpness. we have complained about this for years, here you go.
Zeiss didn't realize that nagging about extreme corner sharpness is a very cool thing to do on forums. It doesn't mean that users want a sharp lens in the corners, it's just that they like to have something to nag about.
Leica definitely knows how to make compact lenses. In fact it is my opinion, that they don't even WANT to produce anything big, because it just doesn't go well with their philosophy and with what their clients expect from them. Look at 16-18-21, a lens that nobody would cry if it was just a bit bigger, but they instead kept it small by using f4. It's not SLR lens, but still I believe that staying small is more important to them than it is to Zeiss.