Some weird lines on smoothed objects

[foundmarble]

Here is what is happening.
Background dark blue

Seperate Layer>>I am making a cloud. I color it white (alpha at 150) with no border.

I use the soft edge on the cloud (setting of 20)

when I render the frame, it will put a thin line either on top or on the bottom of the cloud. Other than that the cloud looks fine.

This wouldn't be such a problem except on a dark background, the line really shows up.

I go back into the soft edge settings at set it to 10....line goes away (or maybe it is still there just not visible?)

Why is this?

[foundmarble]

I am using a white to black(dark grey) gradient on the cloud in addition to the smooth edge

[7feet]

I whipped this up and I see what your talking about. It seems to be resolution dependant, and I don't know what you are rendering at, so to really point it out I did this:



This was rendered at 600x400 and I kicked the soft edge blur up to 80. Don't see it when I get rid of the gradient.

--Brian

[foundmarble]

Thanks for posting a picture!

That is exactly what is happening to me.

I have been getting around this by bringing down the soften edge to about 10 and then bringing my alpha down. I am getting close to the same effect.

Anyway, any suggestions?

[Lost Marble]

The explanation of why this is happening is that the gradient effect is applied to the shape, and not the surrounding area. When the soft edge effect is applied, it has the result of making the shape larger. In turn, this means that the gradient should have been larger to accomodate a bigger shape. Unfortunately, behind the scenes, the gradient effect has no way of knowing this.

The workaround is to use layer blur instead of the soft edge fill effect. I don't know if that would work in your specific situation, but if it does it will fix the problem you're seeing.

[foundmarble]

Thanks for the suggestion and explanation.

I really do appreciate the quick responses!
You guys are great.