In article <36CB2CB3.1D9C7925@snafu.de> , "Lars W." <lar### [at] snafude>
wrote:

> Does POV-Ray only supports 1 bit Alpha Channels, or is there a Trick to use
> more then 1 bit, maybe 8 or 16
> or am i so blind, and it has more than one bit, cause the compositing Programm
> DTA ( Daves Targa Animator 3.0 beta ) converts
> the alpha channel only to an black and White image, even when there are
> transparencies in there ( i removed any Skyspheres for
> testing that ).

The alpha channels should be eight bit for all true color images. If you use
16 per color PNG images you should even get a 16 bit alpha channel. To see
the difference, change the transmit value of the second sphere to something
else, i.e. 0.5. However, the sphere is still a real object for POV-Ray and
it will start calcualtiong all the standard effects for it, so you will see
a high-light in the alpha channel in this case, and the first sphere will
change its color, too.  If you need different alpha channel values for the
easiest way to go might be to simply render the image several times with
different objects being invisible just to get more than one alpha channel.
Adjust the alpha channels and combine them to get one alpha channel.
However, you might need a more powerful tool to do this, a lot of programs
only allow one bit alpha channels.


    Thorsten

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