I’m using a defocus node to create some depth of field in my image, but for some reason it is not showing on the final render. I don’t know if I need to switch a button on or something that I’m missing. The use nodes button is on, and I’ve followed tutorials from wikipedia and such. Does any body have any idea what I’m doing wrong?
You need to be sure to connect the z socket of your render layrer to the node and find out yhow far tthe object is from the camera. You can do the latter by selecting the camera, go to the edit buttons (F9) and enable the “Show Limits” button. Then play with the distance value of the camera until it’s little yellow cross lines up with the object in question. Enter the value that you see into the DoF node (I forget which parameter it is cuz I haven’t palyed with it in a good while) and you should begin to get a nice little blur.
Make sure Do Composite is on as well.
I’ve done both of those, but it still doesn’t seem to work. I’m not sure why.
Make sure you uncheck no z-buffer, so you can use the f-stop setting to make your DoF work.
See Here:
http://wiki.blender.org/index.php/Manual/Compositing_Nodes_Filters#Defocus
It has an example blend you can play with.
I played around with defocus a little. If you can’t see the blur, try setting your fstop to a low value (<5.0) and see if you get some blur.
Edit: If that doesn’t work trying posting a screen grab of your node setup, or posting your blend.
Have you rendered the image normally first in order to fill your renderlayer? (because the Renderlayer node is empty!) After you render it, there should be an image preview at all steps of the way. THEN you press do composite.
Egan makes a good observation. Your renderlayer panel needs to have composite and Z enabled, and thus your RenderLayer input node should be showing something.
Hey, sweet, it worked. 
All I needed to do was press one little button. Could’ve saved a lot of time if I would have known that. Still did though because of you guys, thanks!
if it were only so simple…all the time.