Full Version: Lens Flares and Alpha Channel
Out of all of my graphics programs, A:M does the best sunburst/lens flare effects (due to the high level of options it has). I have been experimenting with alpha channel compositing and it looks like lens flares are masked out with the alpha channel when I composite with Sony Vegas. I inserted a sphere into the scene and it wasn't masked out and whatever parts of the lens flare that were overlapping on the sphere were preserved as well. Does anyone know a way of keeping lens flares from masking out with the alpha channel?
You could render the flares on a black background without other objects in the scene. Then convert the image to gray scale and add it to your alpha channel.
To get the complete alpha at once you can also leave the objects in the scene and make them white with 100% ambiance.
But, maybe someone knows a better way to do this.
To get the complete alpha at once you can also leave the objects in the scene and make them white with 100% ambiance.
But, maybe someone knows a better way to do this.
I'll have to look into that. I just came up with another question about the alpha channel though. Is there a way to render a scene with front projection targets (mixing CGI with live action/photographic elements) and use the alpha channel so that your composite includes the CGI object and its shadow cast on the front projection geometry, but nothing else? I tried this and the front projection target just showed up as black, the only thing that was masked out was the background with no objects in front of it.
What the....? I did this some time ago just by switching on "shadows" in the buffer section of the render properties in V13. I just checked in V14 and the shadow buffer setting is gone 
Does anyone know what has happened to the shadow buffer and if it's still possible to use it?
Does anyone know what has happened to the shadow buffer and if it's still possible to use it?
QUOTE
What the....? I did this some time ago just by switching on "shadows" in the buffer section of the render properties in V13. I just checked in V14 and the shadow buffer setting is gone
Does anyone know what has happened to the shadow buffer and if it's still possible to use it?
Does anyone know what has happened to the shadow buffer and if it's still possible to use it?
I believe the option is context sensitive.
Shadow Buffers will only show up on image/movie file types that support them.
Probably not your problem but worth the effort to investigate.
QUOTE(Luuk Steitner @ Nov 29 2007, 10:59 PM) 
You could render the flares on a black background without other objects in the scene. Then convert the image to gray scale and add it to your alpha channel.
To get the complete alpha at once you can also leave the objects in the scene and make them white with 100% ambiance.
But, maybe someone knows a better way to do this.
To get the complete alpha at once you can also leave the objects in the scene and make them white with 100% ambiance.
But, maybe someone knows a better way to do this.
Have you tried using multipass to get the lensflare with the alpha?
Regarding Luuk's 'render on black' trick...I've done this before and rendered to tga's and then set up a Photoshop action that opens each frame- copies the image-makes a new channel-pastes the image into the new alpha channel (thus removing color info) and adjusts the levels (optional)
The action opens and saves the tga sequence...now you can bring it into Vegas and it will be properly masked.
QUOTE(Rodney @ Nov 30 2007, 10:24 PM)
I believe the option is context sensitive.
Shadow Buffers will only show up on image/movie file types that support them.
Probably not your problem but worth the effort to investigate.
Shadow Buffers will only show up on image/movie file types that support them.
Probably not your problem but worth the effort to investigate.
Ah, you're right! It works with Targa and OpenEXR.
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