How to composite in a background picture?

Question

This is a diagram:

Look at the background carefully...

This background was made in compositing: http://www.filedropper.com/xtruder22

Many thanks

Also you don't have to use an image to get a nice gradient, you can use a gradient texture or colour ramp in blender to generate nice gradients, either as a material on a plane as part of the render or as another render layer or scene to composite into the final. — sambler, Dec 26 '13 at 14:53

gandalf3 · Answer 1 · 2013-12-26T23:55:07.097

8

Another option is an Alpha over node:

Add an Image node (ShiftA> Input > Image) and open your background image:
To crop or scale your background image to fit your render, add a Scale node (ShiftA> Distort > Scale).
Set the Coordinate Space to Render Size, and set the scale type. If your background image is larger than the render, you probably want to crop it. (select Crop) However, if it is smaller and you want to scale it up, select Fit:
Connect the nodes as shown above.

edited Dec 26 '13 at 23:55

answered Dec 25 '13 at 21:57

gandalf3

1

Wondering what version of Blender you're using. Our version 2.69 does not have so many menu items as in your snapshots! – Developer Dec 26 '13 at 03:03
I couldn't do your method. Thanks a lot anyway, I upvoted your answer. – Turbo Dec 26 '13 at 05:25
@Developer I'm using 2.69 too.. Are your sure you were using composite nodes? – gandalf3 Dec 26 '13 at 07:02
Well, not. Now we can find them :) Thanks. Compositing. – Developer Dec 26 '13 at 08:10
@gandalf3 You used Alpha over node when CharlesL used Mix. Which is better? Thanks – Turbo Dec 26 '13 at 10:47
@TimTimmy, I'm not really sure that one is better than the other. However, the mix node allows you to mix it different ways, and I think the alphaover node gives you more control over premultiply. – CharlesL Dec 26 '13 at 14:06
@TimTimmy For just a simple operation like the one above, both will give an identical result. – gandalf3 Dec 26 '13 at 20:33

score 6 · Accepted Answer · answered Dec 25 '13 at 21:36

6

Yes, you can do that with the mix node.

Use the Input > Image node to load in the background image, then use the Mix node with alpha to put it behind.

Node setup: enter image description here

Result:

enter image description here

answered Dec 25 '13 at 21:36

CharlesL

2 Answers2