[Klaus]

You can't disable distortion compensation. Draw your conclusions ... ;-)

[Brightcolours]

Or Lenstip's measurment ;-)
https://www.lenstip.com/558.6-Lens_review-Sony_FE_28_mm_f_2_Distortion.html

[Klaus]

So I shall stop?

[Rover]

4.8% is not too bad... In today's world where a 24mm prime may have 6.1% and a 20mm goes over 8% natively.

[Brightcolours]

4.8% is not too bad... In today's world where a 24mm prime may have 6.1% and a 20mm goes over 8% natively.

Which 24mm and 20mm are those?

---

So I shall stop?

Why? The lenstip measurement was about "draw your own conclusion" (and about that you can get around the correction for review purposes). As long as you enjoy testing lenses the way you do, no reason to stop, right?

[Rover]

The new FE 1:2 Tamrons. The figures are from the EPZ reviews of those. I know their results are sometimes iffy when it comes to resolution, but I think the distortion measurements are harder to botch, are they not? :-)

[Brightcolours]

The new FE 1:2 Tamrons. The figures are from the EPZ reviews of those. I know their results are sometimes iffy when it comes to resolution, but I think the distortion measurements are harder to botch, are they not? :-)

They are harder to compare from website to website, that is why I asked.

To illustrate:
Lenstip finds for the Panasonic 10-25mm f1.7 -5.89% at 10mm. EPZ finds -1.43%. For JPEG lenstip finds -1.24%...

Another example: Canon EF 24mm f1.4 L USM II.
Lenstip: -1.28%
EPZ: -1.94%
For reference, OL: -1.35%

[JJ_SO]

I doubt that any of us, you included, BC, could tell the difference between -1.28%, -1.35% or -1.94% distortion except in direct comparison - and even then: all these testing sites check one copy per lens. It would be sheer luck if two sites found exactly the same value of distortion.

Also, the test charts are in a distance of 25-50 × FL. In the Panasonic case: 25-50 cm away from the sensor. I reckon no one does architecture in this distance? For some optical designs like the ones with floating elements and inner focusing, distortion can depend on FL and distance setting. Less than 2% distortion for a wide-angle already counts as good in my book. For a 10 mm zoom even more so.

[Brightcolours]

Distortion will NOT vary from copy to copy. They all use imatest software to measure, so all should get very similar results. They do not, and I can't tell you why that is.

The difference between 1.28 and 1.94% is quite big and should be pretty noticable (from almost no barrel distortion to some noticable barrel distortion).

The test charts will be the same distance for all 3 sites, so how that affects the different results is unclear to me?

[Rover]

Can distortion be variable from copy to copy? O_o I mean, from one healthy copy to another, not counting damaged or badly decentered lenses.