Sony FE 16-35/f4

[k-hawinkler]

I did. Clearly, both are better, for color transparency, contrast, corner sharpness and, obviously they are 2,8. In particular, as you know having it, the 28 from full open eoutresolves
the
sensor of the a7r on a large part of the image,and, at F8, generates moirè till extreme corners.(probably the sharpest 28 ever built)
But... quality advantage is less than one could think. The 16-35 considering also all other
advantages, is very near. As you do, I am also wandering..
Sergio

Is that a correct statement?
I thought a better lens gives a better image on a given sensor.
And vice versa a better sensor gives a better image with a given lens.
So it's the combination that counts.
Therefore my question. TIA.

K-H, the reply to your question, to avoid to be generic, is neither simple nor short, and requires to cite Nyqvist's theorem, spatial frequency etc.
In practice, let's put the thing this way, if you agree.
A sensor has a resolution that is strictly related the number of pixels in a
defined surface, (pixel density). That resolution can be measured in Line pairs per mm, and in the case of a7r this value is approx. 100 for vertical and horizontal lines. (a little less for oblique)
If the lens has a resolution greater than 100, the part exceeding 100 cannot be
correctly recorded by the sensor, and creates aliasing, better known by photographer as moirè. everytime you see aliasing on a digital image, you know that the lens has more resolution than the sensor. When the sensor reaches its limit, it can no more cooperate with the lens to produce a better image.
I do this measurement with every new lens I get.
If you want, (I esitate to show resolution targets in this forum :sleep006
I can show how I proceed.

Sergio

Many, many thanks Sergio. Please could you show how you proceed.
If you don't want to show resolution targets in this forum could you please post them on dropbox and post the url here so that I can have a look at them. TIA.

So please let me ask you, if I understood your explanation on examples, if I may.

Let's assume a sensor can resolve 100 line pairs per mm (lppm).
Let's also assume the first lens can resolve 100 lppm.
Now if one uses another lens with 200 lppm on that sensor with 100 lppm resolution one doesn't get a better image.
Is that correct?

However, in case of the A7R, if one starts with a lens that resolves less than 100 lppm and then changes to a lens that resolves more lppm that would resolve in a technically better image.
Correct?

I also would appreciate if you could comment on this thread
MTF Curves ~ Sensor Resolution - Leica User Forum
and in particular this post, quote:


"Quote:
Originally Posted by k-hawinkler View Post
I am interested in quantitatively comparing the resolution of Leica lenses with the resolution of digital sensors. So, I would like to know how one can determine whether a given lens outresolves a given sensor and vice versa ...

01af: I wrote so many articles in this topic here in the recent two years ... obviously it was entirely futile.

So let me repeat it once again: Lenses don't outresolve sensors, and sensors don't outresolve lenses. Better lenses are better on any sensor and better sensors are better behind any lens.


Quote:
Originally Posted by k-hawinkler View Post
... or whether the resolution of lens and sensor are comparable.

01af: No, they are not.


Quote:
Originally Posted by k-hawinkler View Post
Do Sensors “Outresolve” Lenses? by Rubén Osuna and Efraín García on Luminous Landscape.

01af: This useless article is full of layman's errors and misconceptions. The maximum useful sensor resolution is not a matter of absolute limits but of return on investment. How much are you willing to spend for further (small) improvement if your current system already is very good?"

Thanks again for your help.

 

[chrisd]

Another from the past weekend:

f8, 1/60s, 16mm, ISO 100, handheld:

 

[sergio lovisolo]

K-H wrote:
"Let's assume a sensor can resolve 100 line pairs per mm (lppm).
Let's also assume the first lens can resolve 100 lppm.
Now if one uses another lens with 200 lppm on that sensor with 100 lppm resolution one doesn't get a better image.
Is that correct?"

Not exactly. You must consider that while sensor resolution is like a wall, (it has the same contrast up to maximum resolution, and past that only aliases) the lens loses contrast progressively. So the lens with a resolution of 100 will have a lower
contrast when reaching the "wall" than that with 200, and the last will produce a better image, but with the potential risk of producing visible aliasing in presence of appropriate patterns.

Reverse also apply, but only in the sense that a sensor with more relative resolution can extract a little more information from the lower part of the contrast curve of a lesser lens, without hitting the wall.

 

[k-hawinkler]

K-H wrote:
"Let's assume a sensor can resolve 100 line pairs per mm (lppm).
Let's also assume the first lens can resolve 100 lppm.
Now if one uses another lens with 200 lppm on that sensor with 100 lppm resolution one doesn't get a better image.
Is that correct?"

Not exactly. You must consider that while sensor resolution is like a wall, (it has the same contrast up to maximum resolution, and past that only aliases) the lens loses contrast progressively. So the lens with a resolution of 100 will have a lower
contrast when reaching the "wall" than that with 200, and the last will produce a better image, but with the potential risk of producing visible aliasing in presence of appropriate patterns.

Reverse also apply, but only in the sense that a sensor with more relative resolution can extract a little more information from the lower part of the contrast curve of a lesser lens, without hitting the wall.

Many thanks again Sergio. I think I am beginning to see what you are getting at.
One more question with regards to the statement by 01af, quote:

"So let me repeat it once again: Lenses don't outresolve sensors, and sensors don't outresolve lenses. Better lenses are better on any sensor and better sensors are better behind any lens."

In its absoluteness, is this statement correct or not, in your view? TIA.

 

[darrellc]

Just bought the FE 16-35. Just looked at a few quick snaps from this evening. At a glance, can tell this lens is much better than my not loved FE 24-70 (it is in my pile of stuff to sell that grows in size and depreciates in value). This plus FE 55/1.8 and some sort of short tele in the 85-105 range could be my default travel kit.

 

[sergio lovisolo]

Many thanks again Sergio. I think I am beginning to see what you are getting at.
One more question with regards to the statement by 01af, quote:

"So let me repeat it once again: Lenses don't outresolve sensors, and sensors don't outresolve lenses. Better lenses are better on any sensor and better sensors are better behind any lens."

In its absoluteness, is this statement correct or not, in your view? TIA.

The second part is (nearly) correct, the first is not. The correlation between the two concepts is an inadequate simplification of the effects of the interaction between
an analog generator (the lens) and an analog to digital converter (the sensor and correlated electronics)

 

[k-hawinkler]

Sergio,

Thank you so much, also for the explanation.

So, how do you go about determining if a lens out-resolves a sensor or vice versa? TIA.

 

[sergio lovisolo]

Sergio,

Thank you so much, also for the explanation.

So, how do you go about determining if a lens out-resolves a sensor or vice versa? TIA.

in photo 1 you'll see a test pattern, prepared following instructions provided by Norman Coren, creator of Imatest, the program used by professionals to test lenses.

photo 2 is a 100% crop of center, showing performance of the elmarit 28-2,8 II
full open. Strong aliasing is visible, centered at 100 lppm, and from the fact that false detail is shown in the area between 100 and 200, we can roughly estimate lens resolution with good contrast up to 130/150.The lens is out resolving the sensor. A precise measurement can be effectuated positioning the camera farther from target.

photo 3 shows performance of the elmarit full open on corner. We can see approx. 90 or slightly more lppm, (a very respectable value) and no aliasing, the sensor is out resolving the lens.
(the elmarit creates aliasing also on corners stopping down to 5,6)

testtarget by sergio lovisolo, on Flickr


elmarit2,8center by sergio lovisolo, on Flickr


elmarit2,8corner by sergio lovisolo, on Flickr

in the last crop is also easy to evaluate the effect of vignetting.

a simple test as this with every new lens for peace of mind.

 

[k-hawinkler]

Sergio,

Many many thanks again.
I greatly appreciate your help.

 

[mjm6]

in photo 1 you'll see a test pattern, prepared following instructions provided by Norman Coren, creator of Imatest, the program used by professionals to test lenses.

photo 2 is a 100% crop of center, showing performance of the elmarit 28-2,8 II
full open. Strong aliasing is visible, centered at 100 lppm, and from the fact that false detail is shown in the area between 100 and 200, we can roughly estimate lens resolution with good contrast up to 130/150.The lens is out resolving the sensor. A precise measurement can be effectuated positioning the camera farther from target.

photo 3 shows performance of the elmarit full open on corner. We can see approx. 90 or slightly more lppm, (a very respectable value) and no aliasing, the sensor is out resolving the lens.
(the elmarit creates aliasing also on corners stopping down to 5,6)

testtarget by sergio lovisolo, on Flickr


elmarit2,8center by sergio lovisolo, on Flickr


elmarit2,8corner by sergio lovisolo, on Flickr

in the last crop is also easy to evaluate the effect of vignetting.

a simple test as this with every new lens for peace of mind.

Aaaah my eyes! I'm blinded by resolution tests! Hahaha...

I agree with Sergio, the first part of that statement is completely incorrect in the context of "individual optical capabilities".

I suspect that despite the sledgehammer approach he used, he may be generally correct in the context of an optical SYSTEM, because at that point, it is the combination of the limitations of every optical component in the chain that results in what you get as the end result.

But, as Sergio points out, moire is an obvious effect that demonstrates that the lens is performing at a higher level than the sensor. When a sensor is capable of higher performance than the lens, you essentially get a faithful reproduction of the limits of the lens.

I suspect that a 50MP sensor will finally show the limits of the best of these 35mm lenses, plus or minus.


---Michael

 

[mjm6]

I will check at home tonight, but until recently, I had a bunch of resolution tests from film scanners that I did about a decade ago, and it is very instructive to see what happens optically to a system as you approach the resolution limits.

If I have them, I'll post a few to discuss in the context of this question.


---Michael

 

[k-hawinkler]

I will check at home tonight, but until recently, I had a bunch of resolution tests from film scanners that I did about a decade ago, and it is very instructive to see what happens optically to a system as you approach the resolution limits.

If I have them, I'll post a few to discuss in the context of this question.


---Michael

Thank you Michael. I am looking forward to your examples. TIA.

 

[k-hawinkler]

Aaaah my eyes! I'm blinded by resolution tests! Hahaha...

I agree with Sergio, the first part of that statement is completely incorrect in the context of "individual optical capabilities".

I suspect that despite the sledgehammer approach he used, he may be generally correct in the context of an optical SYSTEM, because at that point, it is the combination of the limitations of every optical component in the chain that results in what you get as the end result.

But, as Sergio points out, moire is an obvious effect that demonstrates that the lens is performing at a higher level than the sensor. When a sensor is capable of higher performance than the lens, you essentially get a faithful reproduction of the limits of the lens.

I suspect that a 50MP sensor will finally show the limits of the best of these 35mm lenses, plus or minus.


---Michael

Thanks Michael.
IIRC, according to Erwin Puts the Leica APO-R 280/4 resolves 500 lppm and is almost difraction limited wide open.
I have that lens. It truly performs magnificently! So I don't think a 50 MP sensor will show its limits but we'll see.

 

[k-hawinkler]

The second part is (nearly) correct, the first is not. The correlation between the two concepts is an inadequate simplification of the effects of the interaction between
an analog generator (the lens) and an analog to digital converter (the sensor and correlated electronics)

One more question please Sergio. If "The second part is (nearly) correct" then there must be situations for which that isn't true. Could you please describe such a scenario. TIA.

 

[sergio lovisolo]

One more question please Sergio. If "The second part is (nearly) correct" then there must be situations for which that isn't true. Could you please describe such a scenario. TIA.

"better sensor " is a generic definition. The statement is valid for better dynamic range, better iso, better color in general, etc. but not always for resolution, as shown in the preceding reply. If the energy sent by the lens to the sensor is zero
at the native resolution of the "better sensor for resolution", there is no advantage. The lens must always be at least as good to provide some contrast at lppm corresponding to sensor resolution.

 

[k-hawinkler]

Sergio, Thank you. Makes a lot of sense to me.

 

[Paratom]

any more user experience / feedback/ first impressions about the lens? How good is it? How does it compare to 24-70 Zeiss in the 24-35mm range?
Any feedback is welcome - Thank you!

 

[Guy Mancuso]

Quick here ISO 640 F9 at 16mm and 1/60th handheld. Early morning

 

[Guy Mancuso]

No correction with lens profiles but I did crop some

 

[Guy Mancuso]

I knew going in this was going to be maybe a waste of time. Very low light but I had to shoot it anyway. A7r with the 16-35mm. This was a anniversary for John Lennon in Central park at Strawberry fields area. We sat and sang for about a hour and it was a real kick.

This is HANDHELD. Now maybe with the new A7II with IBIS I would certainly have done better.

Shoot at ISO 3200 .4secends at F4 and 16mm

Regardless of the quality its just a cool shot