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render a TFD fire + smoke with alpha
Posted: Tue Jun 07, 2016 5:47 am
by bertritude
Hi, I try to create a fire + smoke test in order to render a sequence with alpha.
I just want the fire + smoke visible on a transparent background. In the LV it works but when I render the sequence, I have the background visible with my fire + smoke with the same parameters of LV.
I don't understand why...
an idea ?
thanks guys
Re: render a TFD fire + smoke with alpha
Posted: Tue Jun 07, 2016 3:13 pm
by bepeg4d
Hi bertritude,
there is no issue with TFD and alpha here, this frame is rendered in the Picture Viewer from the Ahmet TFD example:
Please double check your render settings, I guess that there should be an issue there

ciao beppe
Re: render a TFD fire + smoke with alpha
Posted: Wed Jun 08, 2016 6:35 am
by bertritude
Hi bepeg4d,
thanks for your help. I'll have a look to my settings again.
Re: render a TFD fire + smoke with alpha
Posted: Thu Jun 09, 2016 5:46 am
by bertritude
I tried a 3D tracking scene,
So, I have a look and If I tick the alpha channel in octane settings, I see my animated background the round base for my fire but not the fire itself ine the liveviewer.
If I untick the alpha box, I see a black background and the ship and the full fire this time (my animated background isn't visible now)
Is there a way to have all ?
thanks guys
Re: render a TFD fire + smoke with alpha
Posted: Thu Jun 09, 2016 9:41 am
by bepeg4d
Hi bertritude,
apologize for the crazy screenshot, but I have picked up the first animated texture on my hd
and here everything goes as expected even with an animated background
ciao beppe
Re: render a TFD fire + smoke with alpha
Posted: Thu Jun 09, 2016 11:36 am
by bertritude
whaou, I don't understand...
Maybe it's due to my background material wich is a C4D material with texture and animation. for this, i tick the alpha box in the kernel to make it visible.
please try it with an image sequence in background to see if you have the same thing as me.
Thanks for your help

Re: render a TFD fire + smoke with alpha
Posted: Thu Jun 09, 2016 1:10 pm
by bepeg4d
Hi bertritude,
it's exactly the test that I have already done, there is a c4d material with an image sequence in the color channel. The LV shows the 29th frame while in PV is rendering the 30th frame. If you look carefully, the background is different between the two

Weird, I have no idea why you cannot use the alpha channel option

Could you share one of your scene?
ciao beppe
Re: render a TFD fire + smoke with alpha
Posted: Thu Jun 09, 2016 1:18 pm
by bertritude
ok, no problem. I'll try to send you my project but without the background sequence because it will be too heavy...
Re: render a TFD fire + smoke with alpha
Posted: Thu Jun 09, 2016 1:48 pm
by aoktar
What's the problem? I can see alpha with background+vdb as in image.
Re: render a TFD fire + smoke with alpha
Posted: Fri Jun 10, 2016 5:47 am
by bertritude
Hi,
here is the link to download my scene.
https://drive.google.com/open?id=0B2Eud ... HRHWnduZjg
thanks for your help.
Bertrand