I did some test on Filter Sharpness parameter in the vrayhdri loader and here the results.
I used elliptical filtering algorithm and vray default render setting (using vray 3.50.04)
test has been done with 8 different filter sharpness size : 0.01, 0.1, 1.0, 4.0, 16.0, 64.0, 256.0, 512.0
as expected 512 has a broken result.
you can download all the result images file from here (RGB and sample rate are included in a ZIP file)
Download from Mediafire
you can also view it from my Instagram
https://www.instagram.com/p/BRfvX-4hzLa/
and also view from here
https://flic.kr/s/aHskQAKpPh
0.01.VRaySampleRate0.01.RGB_color
0.1.VRaySampleRate0.1.RGB_color
1.VRaySampleRate1.RGB_color
4.VRaySampleRate4.RGB_color
16.VRaySampleRate16.RGB_color
64.VRaySampleRate64.RGB_color
256.VRaySampleRate256.RGB_color
512.VRaySampleRate512.RGB_color
I used elliptical filtering algorithm and vray default render setting (using vray 3.50.04)
test has been done with 8 different filter sharpness size : 0.01, 0.1, 1.0, 4.0, 16.0, 64.0, 256.0, 512.0
as expected 512 has a broken result.
you can download all the result images file from here (RGB and sample rate are included in a ZIP file)
Download from Mediafire
you can also view it from my Instagram
https://www.instagram.com/p/BRfvX-4hzLa/
and also view from here
https://flic.kr/s/aHskQAKpPh
0.01.VRaySampleRate0.01.RGB_color
0.1.VRaySampleRate0.1.RGB_color
1.VRaySampleRate1.RGB_color
4.VRaySampleRate4.RGB_color
16.VRaySampleRate16.RGB_color
64.VRaySampleRate64.RGB_color
256.VRaySampleRate256.RGB_color
512.VRaySampleRate512.RGB_color
Comment