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You are here: Home / The Bleeding Edge / Sharpness testing, part 2

Sharpness testing, part 2

November 2, 2013 JimK 4 Comments

I wrote a little Matlab program to generate the targets:

sharp target matlab code

And, yes, all you Matlab experts, I know it can be coded a lot more efficiently, even by me. I wrote it this way so that any Java or C programmer could figure it out.

Here’s what a close up of the first four layers looks like:

4 layers

Here’s five layers:

 

5 layers

Six:

6 layers

And, finally, seven, which is what I’m going to start with because it makes it easier to focus:

7 layers

 

The Bleeding Edge, The Last Word

← Sharpness testing Auto-bracketing on the M240 →

Comments

  1. Herb Sennet says

    November 3, 2013 at 6:01 am

    Jim,
    Recently I did some testing because I suspected shutter vibration of the Leica M causing blurred images. This was with adapted lenses and a adapter collar fitted.
    Shooting banknotes at 4 meters distance from a tripod confirmed this for shutter speeds between roughly 1/125 s and 1/4 s. The test results also showed and advantage for Classic mode, in favour of Advanced mode for the Leica M (240).
    With a 75mm M lens and the body attached to the tripod I could not detect any blurring effect.
    The weakest point seems to be the lens collar / adapter collar, in some way bouncing and increasing vibration. Maybe this is something to look for in your setup.
    Thanks for all your very interesting postings.
    With kind regards,
    Herb

    Reply
  2. Jim says

    November 3, 2013 at 6:47 am

    Thanks, Herb, I’ll check into it, providing the test methodology I’m developing is up to the task. I have a Novaflex Nikon F lens to M body adapter on order. I don’t have the Leica R adapter or any R-series lenses, so I won’t be testing those.

    Jim

    Reply
    • Herb Sennet says

      November 3, 2013 at 7:55 am

      Jim, just for your information. I also use the Novoflex LEM / NIK NT adapter. I modified the Novoflex ASTAT MFT collar a bit so it will fit on this adapter.
      Novoflex told me that they have a dedicated collar in development for the LEM /NIK NT.

      Reply
  3. Jim says

    November 3, 2013 at 8:22 am

    Herb, that’s the adapter I have on order. A collar would be a good thing for the intermediate focal lengths, say from 85mm to 135mm. Lenses longer than 135 will probably have their own rotating collar.

    Jim

    Reply

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