I do not know about Bryce at all,,
but you may find many help by Bryce horic guys and admin ^^;
so keep this topic,, and ask again .
then about backdrop,, it is like a decoration which stuck on frame of view. and renderd picture.
it just follow your view movements. it never change,, even though you change view (camera1 camera2,
or Perspective view)
ofcourse you can set backdrop on every scene..
it means you make scene first with figure and props,, and set other background objects,
Once you decide backdrop,, you may need to dicide adjust porps or figures which positon better to
fit the backdrop picture. because you can not change backdrop positon,, or rotate free
and if you set your camera aspect frame, 3 :4, in Render Setting,
you may need to resize your pic to fit the aspect frame.
by Gimp etc,, cut or crop,, the part you want to use as backdrop, which can keep the aspect. 3:4
without it,, the pic stretch or shrink to fit the aspect .frame.
then apply backdrop. it become “background” of the scene. (picture).
when you mix scene object and use backdrop (of sky or envilonment)
you may need to set invisible some part of the scene. like my pic,
Now I set invisible,, ground and walls of the scene set.
then apply backdrop.. (yes I know it is just strange scene , not artistic,, OK,,^^;)
for me,, buck drop is most simple and easy way,, to decorate scene ,and make sky backgropund,,so I love it,,, ^^;
But you may hope to set 3d object as background I think..to make more realistic or good scene,,
I believe other user may help you more ^^;
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