Lost Adventurer, Aleks Kirilenko (3D)
LC #42 Pipers Alley

View Full Version : Fluid alpha

05-17-2006, 03:36 PM
hi all ,
i m working on a short with some fluid effects like fire,smoke , liquids...and i have some problem with the alpha of fluid..
for example , i made a good lookinf fire with the maya fluids , when i render it in maya , everything is ok...but when i import it to combustion the alpha is so light that i can t comp it
i would like to knows yours techniques to get a good alpha to comp , to not loose the look it has in maya...
thanks ...
see you

ps : for thos who has worked in fire shots , how wany and what passes do you make to good a good looking fire....i was thinking of two pass of fire , and one pass of particle to create the refraction of air in comp....if anyone has sugestions... :)

05-17-2006, 04:16 PM
If i understand you correctly, the alpha is too transp?
Check out the Matte Opacity Rollout under the fluid shape node and have a play with those settings. Remember you can always colour correct an alpha channel in post to however you want.

05-17-2006, 04:29 PM
thanks man , you save me some times...

05-17-2006, 05:11 PM
when compositing fire its best to render a separate pass and use it as an additive layer or a lighten/max layer. The alpha on the fire is pretty useless from the fluid examples in the visor

05-22-2006, 03:20 PM
Try Fusion!, its really amazing to see how accurate its alpha channel interpretation is (it works great for me!), ive had this kind of problems in the past while using After Effects to composite Fluids and/or hw rendered particle passes...
Hope this helps!

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