the last word

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

  • site home
  • blog home
  • galleries
  • contact
  • underwater
  • the bleeding edge
You are here: Home / The Last Word / Zeiss 35mm f/2 Biogon ZM on the a7S

Zeiss 35mm f/2 Biogon ZM on the a7S

July 7, 2014 By JimK 5 Comments

I need a break from the lens cap pictures. Let’s see how legacy glass does on the a7S.

The Zeiss 35mm Biogon in the Leica M-series mount is a delightful little lens. Small, and with nice controls, it seems like it was made for cameras like the alpha 7 series. However, it is the toughest of the M-mount lenses that I have for corner smearing. The corners on the a7R make you wince.

I mounted the lens on the a7S using the Novoflex adapter.

First, checking for corner casts with the Expodisc:

f/2
f/2
f/2.8
f/2.8
f/4
f/4
f/5.6
f/5.6
f/8
f/8

 

f/11
f/11

 

f/16
f/16
f/22
f/22

There’s quite a bit of corner falloff at f/2. We can’t blame that on the camera, though. There is no trace of purple corners. In fact, the corners are ever-so-slightly cyan.

I aimed the camera at this scene and made a series of handheld exposures at the whole stops from f/2 through f/22:

_DSC2455-2

Except for diffraction at the narrowest stops, the center was sharp in all cases. Of course, 12 MP doesn’t pose much of a challenge for this lens.

The upper right corner:

f/2
f/2

It’s pretty sharp for wide open, but there’s a lot of flare. I didn’t use a hood. I suppose I should for testing, but I never would when actually using this lens; it would make the camera/lens package just a bit unwieldy. You can’t blame the flare on the camera.

f/2.8
f/2.8

Looking pretty good only one stop down from wide open, but not what you’d call super crisp.

f/4
f/4

Very nice, for a corner.

f/5.6
f/5.6

Probably the sharpest aperture in the center; very good here.

f/8
f/8

Probably the best aperture in the corners.

f/11
f/11

Some diffusion blur in the center, still looking good in the corner.

f/16
f/16

A little diffusion blur

f.22
f.22

Still usable.

This is really good news. If this lens works on the a7S — and it does — I think most any M-series lens will.

[Added 7/10/2014: I was wrong about the universal appicability of the Zeiss 35mm Biogon results. Apparently, I’m going to have to test each and every candidate lens. See here for an example.]

← Sony a7S RN vs ISO corrected for amplifier gain Focus peaking on the a7S →

Comments

  1. Francesco says

    July 9, 2014 at 8:54 am

    Do the color cast depends on the lens or sensor?
    Are you gonna test the leica wate with a7s? I wonder if sony have found a way to solve issues with wa rf lenses.

    Reply
    • Jim says

      July 9, 2014 at 9:13 am

      The color cast changes with the sensor.

      I’m not planning on testing the WATE on the a7S. Since it worked fine on the a7R, there should be no problem on the a7S.

      Jim

      Reply
      • Francesco says

        July 9, 2014 at 10:06 am

        Thanks for your answare.
        My experience is that a7 and wate combo produces blue cast on the edges.

        Reply
        • Jim says

          July 9, 2014 at 10:09 am

          Interesting. I’ve not used the WATE on the a7. I’ll have to try it on the a7S, and probably the a7, to see if I can replicate your results.

          Reply
  2. Francesco says

    July 9, 2014 at 10:06 am

    Thanks for your answare.
    My experience is that a7 and wate combo produces blue cast on the edges.

    Reply

Leave a Reply Cancel reply

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

March 2021
S M T W T F S
 123456
78910111213
14151617181920
21222324252627
28293031  
« Feb    

Articles

  • About
    • Patents and papers about color
    • Who am I?
  • How to…
    • Backing up photographic images
    • How to change email providers
  • 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 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

  • JimK on Zeiss Batis 135 on Nikon Z7
  • Maurin on Zeiss Batis 135 on Nikon Z7
  • Scott Pilla on GFX Natural Live View and raw file histograms
  • Macro Guy on THoS: a NYT infinite loop
  • JimK on Sony 135 mm STF on GFX 50R
  • Alexander Häggström on Sony 135 mm STF on GFX 50R
  • Mike King on Metabones 1.26x Expander on GFX 100 with Otus 55
  • JimK on Diffraction and sensors
  • Barry Benowitz on Diffraction and sensors
  • Raymond on Fuji 45-100/4, 100-200/5.6 on GFX 100

Archives

Unless otherwise noted, all images copyright Jim Kasson.