DOF: Stronger effect towards edges of image

[kosso_olli]

Hey,
I just have a general question here: On some lenses the depth of field effect gets more pronounced towards the edges of the image. Is there a way to replicate this behaviour in V-Ray? I tried all the settings in the Bokeh section of the Physical camera, but to no avail. Maybe I am missing something.

Regards

Oliver

[kosso_olli]

Here are two images to illustrate what I mean. The first image is a crop from the lower edge of the image, but in the center. Notice the crisp detail. The second image is from the exactly the same image, but a crop from the lower right edge of the photo. Notice the stronger blurring. These images are as shot, there is no postproduction. Is there a way to simulate this effect with V-Ray?

[Macker]

I think that's lens distortion (sharpness/CA) rather than depth of field is it not? Almost all camera lenses exhibit this (to varying degrees) towards the perimeter of the image, and in camera lens reviews they use MTF-50 to measure it. I'm not sure it's achievable in the vray cam but it'd be quite easy in post.

[piotrus3333]

It is loss of sharpness. I'm experimenting recently with rendered chromatic aberration. just a polygon in front of cam with refractive shader splitting rays into three colors. when I tried to get axial chromatic aberration (different focus for different parts of spectrum) I lowered refraction glossiness for lets say reds.
do it without bothering with ca, mask it with circular gradient and you should get something.