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**Klaus** · 06-28-2021, 12:05 PM

vignetting: 12.6 f-stops at f/4 and 12.4 f-stops at f/11

Or in other words - beyond anything that Imatest can still measure.

That's without distortion and vignetting correction.

stoppingdown · 06-28-2021, 12:36 PM

Going on with this pace, you'll soon run into a lens whose corners are a black hole... :o)

**Klaus** · 06-28-2021, 12:54 PM

Well, in all fairness - on the R6 (20mp) it's probably a good lens - if you follow the recipe.

**Klaus** · 06-28-2021, 02:13 PM

You will get the juicy horror this week. ;-)

In all fairness - this lens was never meant to be used on an R5 and it is surely nice on an R6 (but then what isn't ...).

And it served a good purpose - we now know what peak vignetting is. ;-)

davidmanze · 06-28-2021, 03:10 PM

(06-28-2021, 02:13 PM)Klaus Wrote: You will get the juicy horror this week. ;-)

In all fairness - this lens was never meant to be used on an R5 and it is surely nice on an R6 (but then what isn't ...).

And it served a good purpose - we now know what peak vignetting is. ;-)

......... check to make sure the lens cap is off ..........

Brightcolours · 06-28-2021, 05:41 PM

Is it worse than with the Canon RF 24-240mm lens (which is actually a nice lens, but you have to use the lens correction for 24mm)?
https://www.photoreview.com.au/wp-conten...G_0095.jpg

toni-a · 06-28-2021, 08:15 PM

The cheaper way is digital correction, those black corners will be cropped out in distortions correction anyway, but still better have it fine straight out of the beginning.

**Klaus** · 06-28-2021, 09:56 PM

(06-28-2021, 05:41 PM)Brightcolours Wrote: Is it worse than with the Canon RF 24-240mm lens (which is actually a nice lens, but you have to use the lens correction for 24mm)?
https://www.photoreview.com.au/wp-conten...G_0095.jpg

wow, no, it's not THAT bad.

Rover · (This post was last modified: 06-29-2021, 07:24 AM by Rover.)

Fine in R6 how? The vignetting (and presumably upper single digits worth of distortion) would just magically go away? Rolleyes

Brightcolours · 06-29-2021, 07:28 AM

(06-29-2021, 07:23 AM)Rover Wrote: Fine in R6 how? The vignetting (and presumably upper single digits worth of distortion) would just magically go away?

No, you are going at it at the wrong angle.

The vignetting is there because Canon decided to leave the wide angle part at least relatively uncorrected (iow: fishe eye alike). They are MEANT to be corrected in camera or in RAW conversion.
When Klaus measures the resolution of the corrected images, he sees that the corners/borders leave something to be desired on the R5 (loss of resolution due to correcting for distortion). The R5 has that 45MP sensor. The R6, with its 20mp sensor, would do better there with this lens, just because of its lower sampling rate.