Cels Forum

Hi ix,

I have a pretty limited knowledge of the production process
of animation cels, but I think most likely the back of your
cel was painted black because the scene in which it was 
shown was backlit.

The extra layer of black is added so that the rest of the
cel can have light shine through it without the light
showing through the painted parts.

Someone with more knowledge can probably explain it
better^_^  Hope this helps!!

Regards,
Lisa (aka LunaArt)