Jump to content

Help me learn about lens signatures


Cadfael_tex

Recommended Posts

I take the heretical view that a perfect lens would have no "signature". Like a perfect Hi-Fi system, it would faithfully reproduce an image of what is in front of it. A lens' signature is the result of its residual aberrations and therefore a consequence of its imperfections. A set of perfect lenses would produce identical images of the same subject.

Not everyone would agree with me.

Alwyn

  • Like 4
Link to post
Share on other sites

Browsing through the galleries on this forum, and/or searching for images taken with specific lenses on Flickr will tell your eyes more than a thousand words...

Also, don't forget that differences in post-processing may greatly affect your perception of a lens' intrinsic contrast, sharpness, vignetting, etc...

Link to post
Share on other sites

I take the heretical view that a perfect lens would have no "signature". Like a perfect Hi-Fi system, it would faithfully reproduce an image of what is in front of it. A lens' signature is the result of its residual aberrations and therefore a consequence of its imperfections. A set of perfect lenses would produce identical images of the same subject.

Not everyone would agree with me.

Alwyn

Ah - but both the perfect hifi system nor the perfect lens exist.

Link to post
Share on other sites

Whilst perfection is relevant and pertinent

 

It's understanding what is important what can be compromised that is key. I don't want to have a HiFi that loses emotion, timing poise and rhythm for a gain in resolution of a cymbal, in the same way I want a lens that captures very fine detail but somehow looks flat and uninteresting

 

You have ultimately got to enjoy putting on a record or CD and enjoy the music, in the same way enjoy your photography and pictures. If you buy secondhand you can try without too much risk of losing much/any money :cool:

Link to post
Share on other sites

I think the OP asks a fair question.

 

We often read on the forums how people love the 'signature' of this or that lens, or own several lenses of the same focal length for their different look. But we rare see any actual photographs to demonstrate the differences. I wonder why?

 

Some lenses clearly have their own look, such as then Noctilux mentioned, but I wonder how many of us would recognise it at f8.

 

Older lenses are generally not as contrasty as the newer versions, but a tweak in photoshop can fix that.

 

One of my favourite lenses is my R Summicron 35, it's the older version. Another member posted some images from their new V3 Summicron M which definately has the same signature as my R lens. I don't know if they are both Mandler designs but will research this.

 

I can't post any images at the moment - OP - but will do so when I can hook up the hard drive to the new computer!

  • Like 1
Link to post
Share on other sites

Advertisement (gone after registration)

If you want to understand lens signatures, a couple of books on photographic optics would be interesting reading. "Lenses in Photography" by Kingslake, "Photographic Lenses" by Neblette, and the "Leica Manual" by Morgan and Lester would be good starting points.

 

Many modern optical engineers would agree with the statements made above that a lens should not have a signature, but faithfully reproduce an image. Fortunately, with Leica you have an 80-year selection of lenses designed by engineers making compromises. The Zeiss C-Sonnar 50/1.5 is an example of a modern lens that recreates a lot of famous imperfections.

 

I have a good sampling of lenses made over the last 80 years.

 

- Mu-43 Gallery

 

- SeriousCompacts.com Gallery

 

1936 Carl Zeiss Jena 5cm F1.5 converted to Leica Mount, wide-open on the Leica M9:

 

7456581582_41f466341b_z.jpg

1936 Sonnar 5cm F1.5, wide-open on the Leica M9 by anachronist1, on Flickr

This particular lens is factory coated, one of the earliest. The coating is in amazingly good condition. I think they might be practical for longterm application.

 

Zeiss C-Sonnar 50/1.5 wide-open on the Leica M8:

 

7456495092_a5717c9feb_z.jpg

C-Sonnar 50/1.5, wide-open on the Leica M8 by anachronist1, on Flickr

 

read the books and you too can say "I just love that over-corrected for spherical aberration look" and "Just feel like an Asymmetric Lens today".

 

7187990803_f89606e9ff_z.jpg

Dewdrop, 1936 CZJ Sonnar 5cm F1.5, wide-open by anachronist1, on Flickr

Edited by brianv
  • Like 2
Link to post
Share on other sites

I will try with two images. One is from the Zeiss 35 2.8 Biogon, a bitingly sharp lens. It almost has a view camera look -- and I have shot a lot of 8x10 in my life. The other is 28 mm Version 4 Elmarit. Frankly, I find the Zeiss too sharp -- it has a tendency to produce artefacts. The Elmarit is ideal to me -- fine resolution, and an all around smoothness. Having said that, you probably won't see the difference in the small jpegs. In a 36 inch print, the difference is clear.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

  • Like 1
Link to post
Share on other sites

I have one lens which used steel in the barrel that was formulated to match the coefficient of expansion of the optics. It maintained focus across temperature range. Light rays entering the front element pass through the lens as a front, and maintained phase as they formed an image. I worked with the optical engineers that designed it, and they worried that no one could actually make it. The lens cost $40K to manufacture almost 30 years ago. Someday I need to mount it on a camera, it was used in an optical computer.

  • Like 1
Link to post
Share on other sites

I've been doing some side by side testing of my three fifties lately.

These comparisons only show a small reflection of what they are about so of course one will be better to "your" eye in varying scenarios.

Here you can see the Summilux and Noctilux have warmer colors for foliage:

 

Which do you prefer? 50 mm comparisons: Leica Talk Forum: Digital Photography Review

 

Here are some Summilux vs. Noctilux and they are basically the same except for a little extra DOF:

Summilx3-Edit | Flickr - Photo Sharing!

Noctilux3-Edit | Flickr - Photo Sharing!

Summilux4-Edit | Flickr - Photo Sharing!

Noctilux4-Edit | Flickr - Photo Sharing!

Noctilux1 | Flickr - Photo Sharing!

Summilux1 | Flickr - Photo Sharing!

  • Like 1
Link to post
Share on other sites

The perfect lens will create images that, when displayed, will immediately make all Godfearing men and women fall to their knees and cry tears of joy.

 

Until then... we will have a parade of ever-newer lenses that convince us that the flaws of our current lenses render them incapable of producing adequate images

  • Like 2
Link to post
Share on other sites

read the books and you too can say "I just love that over-corrected for spherical aberration look" and "Just feel like an Asymmetric Lens today".

 

I love that statement :)

 

while there are differences in contrast, resolution, illumiation and abbereations as well as color, these are only defects or compromises.

 

80% of the forum talk about particular lenses having "glow", "3Dness" [sic!], etc. are just esotherics. The differences people see often times have much more to do with the scene photographed. Whats in the background, how was the light, what distance and focal lenght...etc.

 

the 20% that remain are that...defects.

  • Like 2
Link to post
Share on other sites

Life is not perfect. It is full of flaws and is all the more beautiful and intriguing for it.

 

The same can be said for most lenses; their compromises and flaws add character. This individual 'signature' can be exploited for creative effect.

 

With the amount of post processing work carried out in the digital world, though, it is hard to be sure whether the 'look' of the image you are viewing is intrinsically linked to the lens used.

Link to post
Share on other sites

Perhaps a naive reply, but isn't what the original poster is getting at is the difference between various Leica lenses of the same focal length? And with a few exceptions, in my experience the way we generally think about this is how do the lenses render when wide open. Yes, Tony is correct, at f/8 it is harder to tell the difference. But at f/2, we really can tell the difference between a pre-Asph 35mm Summicron Version IV and, say, the 35mm Summilux FLE. We can all take it too far, and be lens snobs, and show erudition (fake or real), but there is a difference between various lenses, and when we judge their *signature*, aren't we usually talking about how they look wide open, first and foremost, and then stopped down a few stops?

 

And to that end, it really would be helpful to see more of what Bpalme has done, and the recent comparison someone did of various 35mm Summicrons. There is a difference between various Summiluxes and Summicrons, and in several cases, people like the signature of the less expensive lenses. It would be nice to have not only an Erwin Puts technical analysis, but also actual images to compare, in some systematic fashion.

Link to post
Share on other sites

I think the best place to start with lens rendering is decide what kind of photos you want to take. Dreamy? Gritty? Reality? Soft? Strong? Beautiful? natural? Unnatural? Unnerving? Then take it from there. And the forum is a great place to ask - i want a dreamy lens which shall I look for?

 

Once you have couple lens names, go to Flickr and just type in the name of the lens in the search field. You will find there are Flickr Groups for each of the lenses normally. Then browse away and note what you like or don't like. You can search for the relevant discussions and photos here too. Ask more questions and search some more. The process is not something that is quick because it really depends on your taste and if you're not sure what that is yet then it takes time to find that.

 

Just the same with with any aspect of photography, point of view comes first and gear second to communicate it.

 

Good luck and have fun.

  • Like 2
Link to post
Share on other sites

yep. The most important thing with buying photo gear is to FIRST define the mission, and then buy the tool to accomplish it.

I alwaysget the creeps when some guy on dpreview (or similar) says that he has a "gap" in his lens line up (for example between his 17-50 zoom and his 70-200 zoom) and that he thinks about a 60mm lens to fill it :)

  • Like 2
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...