alpha or opacity on layers

Hi,

i have a question.
i own toon boom animate pro.
i am doing a christmas animation.
i have some psd file and layer that must appear from the top of the screen
to the end of the screen, and i need to set the alpha to 0 in the top and
arrive to full opacity at the background, how can i do it?

thank you
francesco

try this thread http://www.toonboom.com/support/forums/animate/index.php?board=17;action=display;threadid=2579