Highlight with jagged edges

[notamondayfan]

Hey all,

Little (slightly urgent) help needed. I have a metal edge, and the spec highlights are too jagged. I've tried increasing AA to 1/100, sub pixel mapping, clamping, but not luck.

It's for an animation, and is quite noticeable on the shot.

Any ideas?

Cheers

[notamondayfan]

I've just been playing with the filter, and it seems like changing to quadratic might help / solve the issue.

[^Lele^]

You can make the reflections more rough on that material, thereby lowering the intensity of those pixels, or you could lower the reflection contribution for the light(s).
If neither is a go, you can do the "real" thing, and add a lens effect on top: small the radius as it may be, it'll give you a much nicer, and physically accurate, result than the straight render ever could.

Filtering of the image will surely cure this, at the expense of every other fine detail, however.

[notamondayfan]

I tried the lens effects, but the effect was too great on parts of the image I didn't want it to happen, and too low on the areas I needed it. I'm testing the quadratic filter now, luckly the scene doesn't have too many small details, so a bit of blurring shouldn't be a problem

[^Lele^]

Big filters will also incur in semi-serious penalties at rendertime, just something to be aware of when the total render time tends to be big (ie. in animations.).

[notamondayfan]

I've just compared the render times from using area to quadratic, and there's a 2% increase. Just waiting to download the files to see if the issue has disappeared or not. Fingers crossed!!

[notamondayfan]

Quadratic totally did the trick, and well worth the slight render times. It's also seems just as sharp on smaller details as area too.

[^Lele^]

https://docs.chaosgroup.com/display/...X/Image+Filter

You can always refer there to see how much detail you're going to lose on ~pixel sized detail.
Render times will grow the bigger the filter area is (f.e. cubic, soften, video).
How much loss of detail, and rendertime increase, one can live with is highly opinable, indeed.

[notamondayfan]

Totally agree, and thanks for the link. In my first test, the highlights moving over the fine edge were distracting, and knew the client would pick up on this (plus I wasn't happy either). The difference in sharpness is negligible, same as the render times, so in this instance I'm happy to make this trade off.

I will look further into the post effects though, but my initial tests weren't successful / didn't make a significant difference.

Cheers!