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You are here: Home / GFX 100S / Fujifilm 20-35/4 GF distortion

Fujifilm 20-35/4 GF distortion

October 6, 2022 JimK 1 Comment

I’ve received requests to take a look at the distortion of the Fujifilm 20-35/4 GF on the GFX 100S. This being a thoroughly modern lens on an equally-modern camera, there are two kinds of distortion to consider. The first is the distortion the lens produces on the sensor, and the second is what you see after the distortion has been corrected automagically in your raw developer.

“Wait a minute!” I hear you saying, “If the distortion is corrected without my doing anything, how can we look at what it was before it was corrected?”

Good question.

The camera does not actually correct the distortion. It merely puts instructions in the metadata that tell the raw developer to correct the distortion. Some raw developers, like Lightroom (Lr) and Adobe Camera Raw, look at the metadata and silently perform the corrections. Then you never see what the lens is actually doing. But some raw developers either ignore the correction instructions entirely or allow the user to defeat them. I used RawDigger to evade the corrections — which Lightroom may or may not be performing for a lens this new.

20mm

There is some barrel distortion at 20 mm.

28mm

There’s a little pincushion distortion at 28mm.

35mm

There’s a lot of pincushion distortion at 35mm.

Now we’ll look at how well Lr corrects the distortion with the default settings.

20mm

 

Darned near perfect.

28mm

Excellent.

35mm

Hard to beat that.

 

GFX 100S

← Fuji 20-35/4 landscape field curvature at 23mm vs 23/4 GF Fuji 20-35/4 vs 32-64/4 landscape field curvature →

Comments

  1. Troy says

    October 6, 2022 at 11:11 am

    From what I’ve seen so far this is a 20-30mm zoom which is great!

    Reply

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