Opacity map leaves artifacts on edges of plane *PHOTO*

[Anonymous]

Hi Folks

I've been using the TIFF alpha channel to make part of the image translucent. Normally, it works fine. Occasionally, there are some artifacts caused by bleeding around the edges of the:
- object
- edges of the plane

Following some tips elsewhere, I have already tweaked the following settings in Max:
- turned tiling off
- turned premultiplied alpha off
- set diffuse, specular, ambient colors to black
- set specular level, glossiness to zero

Thanks for your help!
David

[Steve_Curley]

Bitmap > Coordinates rollout > Blur (turn it down as far as it will go).
Check your alpha channel very carefully - could well have been anti-aliased against the background when it was created.

[Anonymous]

Hi Steve, thanks for your reply.

Changing the blur didn't help, unfortunately.

The alpha looks fine, as far as I can tell. I've created new ones several times, with identical results. I've tried TGA formats too, still identical. In addition, I've painted in black over the artifact areas on the alpha channel in PhotoShop.

How can I stop it from being anti-aliased against the background in PhotoShop?

[Steve_Curley]

Should be a way, but as I don't have PS I can't help with the specifics.

[Anonymous]

I've spent a couple more hours on this issue, still the same problem.

Here is another image, with the artifacts on the edges of the flat plane (it is just a plane with the image applied).

It is the same result, whether I use TIF and TARGA with an Alpha channel, or whether I use another image as an Alpha mask.

Please help! 🙂

[Midge_S]

You could put a planar UVW Map on the plane and make it slightly smaller than the object.
Then in your bitmap map settings turn off tiling.

What you're seeing is a slight mismatch between the plane and its UV's, which is causing the image to tile over its edge and repeat on the other side.

Also, a good way to prevent the white border on your transparency is to make the background colour of your image the same as colour of the border of your image in Photoshop.

Hope that helped!

M.