Differing video pre and post render size?

Hi Guys,
Trying to add a lightsaber effect over live video footage, the special effect seems to work fine in regards blur effect and tracking against live video footage when tracking frame by frame in the editor screen but once I get to adding the final node which is adding the video background footage (1920x1080p) ready for render it shows the background footage as much smaller than in the editor viewer but the lightsaber/ cylinder remains the correct size in the rendered image. Why?

In the camera view in the editor the background image is the right size and fits perfectly. Once the video footage is added in the node editor its much smaller.

Rendered screen grab without video node:


Rendered image with node video node added:


This is currently how I have the nodes set up (final part anyway):


Fairly new to Blender as in I thought I knew the basics and this forum tutorials and Q&A has helped a huge amount but I’m stumped with this one???
Probably doing something wrong which is dead basic but I can’t see it?
Please help.

Is the video clip 1920 x 1080? Blender won’t scale it up unless you tell it to.

Thanks, I was thinking it would be something like this. I put the render preset to 1920 x 1080 as shown in the images above but should I be doing this somewhere else too?

Add a Scale node after the image input node.

Your an absolute diamond! Thank you Organic.
For anyone who is unsure what was required I’ve taken a screen grab of the node that was missing in order for this project to display correctly.


You really should try to shoot at the final size (or bigger), instead of blowing the shot up to render size. You are oversampling the render needlessly. What are the dimensions of the source footage? Click on the node and check it’s properties in the panel on the right.