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ajacob
06-04-2013, 12:46 PM
I was working on a scene which needed 32 bit tiff files output.
Everything was working nicely. I realized I needed 2 mattes for compositing in After Effects.
Worked perfectly on the first object, outputting everything on a transparent background.
When I switched the matte on the objects, I lost the alpha. No matter what I tried, 32 bits file wouldn't work anymore.
The scene file was corrupted somehow, took me hours to figure it out.
I had to open a prior version and imported the changes (camera and light) from the corrupted file....and it worked!

Is it something new? Has anybody hit that snag?

A.

ajacob
06-05-2013, 04:17 PM
After some tests, it seems that this is a bug with rendering alpha (32 bits tiff) in Lightwave 11.5
But, there's an easy solution....you have to do 2 render of the same object.
First one normal on a black background and the second one white matte on a black background using 24 bits tiff instead.
A bit more work but.....it works.

Come on Lightwave team, this is a basic thing.
Don't make us work twice as hard beause of a stupid bug.

Airwaves
06-06-2013, 08:41 PM
So I am a newbie but it sounds like the same questions I have. So I rendered out two images of a character to paste on a website. I did one of the character with no background and the other was the alpha. I saw on this old forum that they said you can remove the background in photoshop by using the alpha image in the channel.

Does anyone know how to remove the background so it is transparent in photoshop using LIghtwave? I followed this old forum thing and I just do not know how to do it.

http://forums.cgsociety.org/archive/index.php/t-1847.html

dwburman
06-06-2013, 09:03 PM
Could you not use the Save Alpha function on the Render Globals Output and render once? I agree that this needs to be fixed.


After some tests, it seems that this is a bug with rendering alpha (32 bits tiff) in Lightwave 11.5
But, there's an easy solution....you have to do 2 render of the same object.
First one normal on a black background and the second one white matte on a black background using 24 bits tiff instead.
A bit more work but.....it works.

Come on Lightwave team, this is a basic thing.
Don't make us work twice as hard beause of a stupid bug.

BigHache
06-07-2013, 05:48 AM
A stupid question, why TIFF instead of something like say TGA?

Airwaves
06-07-2013, 09:19 AM
Could you not use the Save Alpha function on the Render Globals Output and render once? I agree that this needs to be fixed.

Are you saying you can render the image just once in Lightwave and when you pull it into photoshop it will have another layer or channel so you can delete the background? I am confused.