• site home
  • blog home
  • galleries
  • contact
  • underwater
  • the bleeding edge

the last word

Photography meets digital computer technology. Photography wins -- most of the time.

You are here: Home / The Last Word / Leica 28mm f/2.8 Elmarit on the Sony a7S…

Leica 28mm f/2.8 Elmarit on the Sony a7S…

July 10, 2014 JimK 6 Comments

…and, as a bonus, on the Leica M240.

When I tested the Zeiss 35 mm f/2 Biogon ZM on the a7S, I thought it was the worst-case lens for the camera.

Wrong.

I received a request to try the Leica 28mm f/2.8 Elmarit ASPH on the a7S. “Why not?” I thought, but I didn’t really expect a problem. The first set of results were so bad that I thought I’d screwed up somehow. I went back and re-tested, this time with the camera on a tripod, and critically focusing with a loupe on the LCD screen.

Still bad.

Focus curvature? Could be. I went back and used the a7S’s great movable magnified live view — are you listening, Leica? — to focus on the upper right corner. Better, but still not great.

I put the lens on the Leica M240 and clipped the camera into the tripod. That’s more like it. The 28mm Elmarit is never going to be the sharpest lens in the drawer, but it’s much better on the Leica than on the Sony.

Here come the images. I’ll leave out the Expodisc pictures. All you need to know is the 28mm Elmarit on the a7S has virtually no corner casts.

The scene with the a7S:

_DSC2818

The scene with the M240. Notice the large differences in color rendering. All images developed in Lr 5.5. WB set to Daylight:

L1000005

Tight crops of the upper right corner, scaled to compensate approximately for the resolution differences between the two cameras.

Note: the 28 exhibits some curvature of field. Since I could put the magnified live vie rectangle anywhere I wanted to with the Sony, I put it right on the tree in the upper right, thus compensating for curvature of field. With the M240, I didn’t have that option, so I focused in the center of the frame. As it turned out, the Leica won walking away anyway:

a7S f/2.8

a7S f/2.8

M240 f/2.8

M240 f/2.8

The Sony is much blurrier.

a7S f/4
a7S f/4

M240 f/4

M240 f/4

The Sony is still blurrier. This is a much larger difference than could be explained my the sensor resolution difference.

a7S f/5.6
a7S f/5.6

M240 f/5.6

M240 f/5.6

At f/5.6, the quality of the two images is beginning to converge, but the Leica is still the winner.

a7S f/8
a7S f/8
M240 f/8
M240 f/8

By f/8 it’s about a tie.

a7S f/11
a7S f/11
M240 f/11
M240 f/11

The parity continues at f/11.

a7S f/16
a7S f/16
M240 f/16
M240 f/16

Diffraction is starting to rear its ugly head, and the two cameras are neck and neck.

a7S f/22
a7S f/22
M240 f/22
M240 f/22

Both images are equally soft.

 

 

 

 

The Last Word

← Leica WATE on the a7S at 21 mm 50 Summilux & 55 Otus on the Sony a7S →

Comments

  1. Anu says

    July 10, 2014 at 12:56 am

    Maybe the A7S has very thick AA-filter? I imagine that is the case due to the low resolution needing significant blur to prevent alising. That should explain the hideous corners.

    Can you test the field curvature of a lens between A7S, A7 and A7r? This could give some interesting results. A7 certainly increases the field curvature significantly for lenses with exit pupil even moderately close to the image plane (CV 50/1.5 has exit pupil at approximately 46.5mm, yet the field curvature increase is significant, the CV 12/5.6 with it’s approx. 30mm exit pupil distance has absolutely ridicilous field curvature on A7.

    Excellent blog btw, I really enjoy reading it.

    Reply
    • Jim says

      July 10, 2014 at 7:52 am

      Can you test the field curvature of a lens between A7S, A7 and A7r? This could give some interesting results.

      It could, but I don’t have a way to test field curvature. I can tell if it’s there, but I can’t measure it.

      Jim

      Reply
  2. Jack Hogan says

    July 11, 2014 at 4:58 am

    Hi Jim,

    Yeah, could differing sensor stacks justify the difference in performance between the two bodies? http://www.lensrentals.com/blog/2014/07/sensor-stack-thickness-part-iii-the-summary

    Reply
    • Jim says

      July 11, 2014 at 8:05 am

      Jack, I doubt if Sony has differing cover glass thickness across their E-mount camera line. If they did, their own E-mount lenses would give inconsistent corner performance, and they sure don’t want that.

      I’m now thinking that the corner color casts are mostly (entirely?) due to the sensor itself, with larger pixels giving more neutral corners. I think the nature of the corner smearing is also dependent on sensor resolution, with smaller-pixel sensors being able to resolve the smearing better, and thus the problem appears worse on the smaller-pixel sensors.

      There are probably effects of the microlenses and the constriction of the photodetectors themselves, but I know of no way to get a handle on that.

      Not simple…

      Jim

      Reply
  3. Heiner says

    August 13, 2015 at 11:32 am

    Hello,
    if it is really a problem with the micro lenses, do you think it would be possible to correct for it with another lens, e.g. like the Metabones Speedsters do for FF lenses on APS-C bodies?
    Heiner

    Reply
  4. Euda half says

    August 4, 2017 at 3:11 am

    leica made microlens shift of sensor from center to corner . since m9 for their lens

    Reply

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

May 2025
S M T W T F S
 123
45678910
11121314151617
18192021222324
25262728293031
« Apr    

Articles

  • About
    • Patents and papers about color
    • Who am I?
  • How to…
    • Backing up photographic images
    • How to change email providers
    • How to shoot slanted edge images for me
  • Lens screening testing
    • Equipment and Software
    • Examples
      • Bad and OK 200-600 at 600
      • Excellent 180-400 zoom
      • Fair 14-30mm zoom
      • Good 100-200 mm MF zoom
      • Good 100-400 zoom
      • Good 100mm lens on P1 P45+
      • Good 120mm MF lens
      • Good 18mm FF lens
      • Good 24-105 mm FF lens
      • Good 24-70 FF zoom
      • Good 35 mm FF lens
      • Good 35-70 MF lens
      • Good 60 mm lens on IQ3-100
      • Good 63 mm MF lens
      • Good 65 mm FF lens
      • Good 85 mm FF lens
      • Good and bad 25mm FF lenses
      • Good zoom at 24 mm
      • Marginal 18mm lens
      • Marginal 35mm FF lens
      • Mildly problematic 55 mm FF lens
      • OK 16-35mm zoom
      • OK 60mm lens on P1 P45+
      • OK Sony 600mm f/4
      • Pretty good 16-35 FF zoom
      • Pretty good 90mm FF lens
      • Problematic 400 mm FF lens
      • Tilted 20 mm f/1.8 FF lens
      • Tilted 30 mm MF lens
      • Tilted 50 mm FF lens
      • Two 15mm FF lenses
    • Found a problem – now what?
    • Goals for this test
    • Minimum target distances
      • MFT
      • APS-C
      • Full frame
      • Small medium format
    • Printable Siemens Star targets
    • Target size on sensor
      • MFT
      • APS-C
      • Full frame
      • Small medium format
    • Test instructions — postproduction
    • Test instructions — reading the images
    • Test instructions – capture
    • Theory of the test
    • What’s wrong with conventional lens screening?
  • Previsualization heresy
  • Privacy Policy
  • Recommended photographic web sites
  • Using in-camera histograms for ETTR
    • Acknowledgments
    • Why ETTR?
    • Normal in-camera histograms
    • Image processing for in-camera histograms
    • Making the in-camera histogram closely represent the raw histogram
    • Shortcuts to UniWB
    • Preparing for monitor-based UniWB
    • A one-step UniWB procedure
    • The math behind the one-step method
    • Iteration using Newton’s Method

Category List

Recent Comments

  • Mike MacDonald on Your photograph looks like a painting?
  • bob lozano on The 16-Bit Fallacy: Why More Isn’t Always Better in Medium Format Cameras
  • JimK on Goldilocks and the three flashes
  • DC Wedding Photographer on Goldilocks and the three flashes
  • Wedding Photographer in DC on The 16-Bit Fallacy: Why More Isn’t Always Better in Medium Format Cameras
  • JimK on Fujifilm GFX 100S II precision
  • Renjie Zhu on Fujifilm GFX 100S II precision
  • JimK on Fuji 20-35/4 landscape field curvature at 23mm vs 23/4 GF
  • Ivo de Man on Fuji 20-35/4 landscape field curvature at 23mm vs 23/4 GF
  • JimK on Fuji 20-35/4 landscape field curvature at 23mm vs 23/4 GF

Archives

Copyright © 2025 · Daily Dish Pro On Genesis Framework · WordPress · Log in

Unless otherwise noted, all images copyright Jim Kasson.