• 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 / GFX 50S / Leica Q2 Monochrom vs GFX 50S — red Siemens star

Leica Q2 Monochrom vs GFX 50S — red Siemens star

May 15, 2022 JimK Leave a Comment

This is the third post in a series about the Leica Q2 Monochrom. You can see all the other posts in the series by looking in the Category List drop-down menu on the right side of the page.

Some people who read yesterday’s post asked about differences between the GFX 50S and the Leica Q2 Monochrom in highly chromatic light that only excites one CFA color plane in a Bayer-CFA camera. I used to do those tests using a #29 and #47 filter over the lens. I went looking, and found the two 77mm filters. But I couldn’t find my step-up ring collection. I seem to remember  that, a year or so ago, I gathered all my step-up rings together and put them in A Safe Place. You know how that goes. I can’t find them.

So I printed a red sinusoidal Siemens star target.

To get equivalent diffraction, I shot the Q2 at f/4, and the GFX at f/5.6.

The details:

  • Low-contrast sinusoidal Siemens star chart
  • RRS carbon fiber legs, Arca C1 head
  • Manual focusing with max enlargement and peaking
  • 4 shots at each condition, keep only the sharpest one.
  • 2-second self timer delay
  • Sharpening turned off in Lr
  • Contrast increased in Lr by the same amount for the two sets of captures

The color version of the star with the GFX, at a bit over 100%:

The B&W version of the GFX image:

GFX f/5.6

 

The Q2 Monochrom image:

 

Q2 f/4

The Q2 has far less aliasing. In addition, the spatial frequency of the aliased components is in general of higher spatial frequency, which makes them less objectionable.

Lr’s Enhanced demosaicing of the GFX image doesn’t help much:

GFX f/5.6 Enhanced

GFX 50S, Leica Q2 Monochrom

← Leica Q2 Monochrom vs GFX 50S — Siemens star Leica Q2 has a real raw histogram →

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Your email address will not be published.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

  • JimK on How Sensor Noise Scales with Exposure Time
  • Štěpán Kaňa on Calculating reach for wildlife photography
  • Štěpán Kaňa on How Sensor Noise Scales with Exposure Time
  • JimK on Calculating reach for wildlife photography
  • Geofrey on Calculating reach for wildlife photography
  • JimK on Calculating reach for wildlife photography
  • Geofrey on Calculating reach for wildlife photography
  • Javier Sanchez on The 16-Bit Fallacy: Why More Isn’t Always Better in Medium Format Cameras
  • Mike MacDonald on Your photograph looks like a painting?
  • Mike MacDonald on Your photograph looks like a painting?

Archives

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

Unless otherwise noted, all images copyright Jim Kasson.