View Full Version : XA20 Vignetting at full zoom with Image Stabilization on.


James Larkey
October 26th, 2013, 07:59 PM
I have an XA20 and love it except for the constant vignetting at full zoom. I mainly video airplane shows and the vignetting is very visible against the blue sky.

I noticed online that it appears to only be an issue when Image Stabilization is turned on (which I need to use).

Anyone else with the problem? I have never contacted a Canon repair/warranty center but may have to.

Some examples of the same problem I am having from other owners.

Thanks,

James

XA20 Vignetting Effect Bug on Vimeo

More on YouTube

Defecto en Canon XA20 con estabilización - CanonXA20 stabilization issue defect fault - YouTube
Canon XA20 with vignetting fault in Zoom with stabilitation - YouTube
Canon XA20 vignetting bug when use the stabilitation in 15- - YouTube
Canon XA20 vignetting fault when use IS and Zoom Test - 001 - YouTube

Don Palomaki
October 27th, 2013, 06:46 AM
All lenses vignette, even expensive ones. It is more pronounced with wide range zoom - more compromises made. You can verify this by reading lens reviews in photo magazines.

The dancing of the vignetting is a by product of IS. For talking purpose, lets assume the subject of interest is in the center of the image at at time zero. As the camera shakes/moves, the lens no longer points at the subject - the subject is closer to a corner.of the image where the vignetting is more pronounced. IS compensates for this movement by trying to bring the subject back to the center and as a result exposes more vignetting from one corner and less from the opposite corner. I would expect this to be more pronounced with IS schemes that compensate by sensor movement or adjusting the area of the sensor that is sampled - probably dynamic and power.

For many types of image content this is not an issue because the vignetting is masked by the image details and viewer focus ins on the subject, not the background, but for flat backgrounds it can be.

The solution may be to use a very stable camera support and scale back on the use of IS.