How to have transparents decals without shadows under ?

[oudou]

Hi, I'm trying to put some decals like one glued to a wall, on a plane, with one material for the gfx on the decal, another material is fully transparent, and there is a mix texture for blending them.
The space between wall and decal is about 0.001 cm. My problem is when transparent material is close from wall, it casting a shade on it. I've done lot of tests, same result.
The only solution i have now is to vectorize the decal and import it as .ai in max, but that just a workaround...

Here a screen for exemple :


any ideas ??

[gabrielefx]

why you use mix material?

put the mask in the opacity slot of a glossy mat

[oudou]

yeah, i also tested it like this before, same results... (and i tried mixing with other types of materials too)
screen with only a glossy mat + opacity map. Png is 24b, same results with 8b, 24b without alpha, and 24b jpg, i checked that white is really white too.



When the plane is less close, things goes better... that's like an AO effect
Same things with PCM too

[wisemanxxx]

did you try to set alpha image's gamma value to 2.2?

[oudou]

Yes, i did...
There isn't problems for you to do this ???

[profbetis]

lol dude you forgot to turn on alpha shadows!

[oudou]

!!! So simple, ho, i go hide myself behind a pile of triangles...
Thanks, i had misunderstanding use for this switch (i was thinking it was only about the matte fonction...)!!