Compositing nodes not showing image preview

I’m trying to do some little vignette tricks to the rendered image that I left rendering all this afternoon, but even after I plug everything, their little “tiny windows” never show a single preview of what the filters are doing!

Also, when I tossed the Output Viewer to see it at least as backdrop, the image is HUGE and I can’t seem to find a way to zoom out to at least get to glimpse the borders of the picture and see if the vignette is cool or not.

Did I forget to toggle on something? I’m following a simple tutorial to make a vignette and his previews do show. Also I think I should mention that I rendered a FRAME of a movie because I had some particles that needed to roll for some seconds before I picked up the one that had the particles looking good.

Attachments


select the node and press shift+h

The little sphere up in the right corner of each node is the preview image button. Click those to open and close the little previews.

To zoom in and out of the backdrop, hit V or Alt V. Or press N to open the properties panel on the right side of the node view and look at the Backdrop panel. Controls are there.