Camera Tracking - Nuke 101: Professional Compositing and Visual Effects - page 437

Usually, you use the Reformat node to change the resolution of an image. If you
have an image that's full HD (1920×1080), for example, and you want it to be a
720p format (1280×720), this is the node to use. It can also change the format of
an image beyond just resolution, change its pixel aspect ratio, and depending on
the properties, crop an image (though that's rarely used).
Inthiscase,usingaReformatnodeisaneasywaytospecifyresolution.Youdon't
really need a background image for the ScanlineRender node, you just need to
enter a resolution, and so a Reformat node is perfect.
9. ChooseToBoxfromtheTypedrop-downmenuonReformat1'sProperties panel.
This option lets you enter width and height values without having to create a new
format.
10. Check the Force This Shape check box to enable both the Width and Height
fields. Otherwise, you will only be able to specify Width, and Height will be cal-
culated with aspect ratio maintained.
11. Enter 2000 in the Width field and 1000 in the Height field.
12. Connect ScanlineRender1's bg input to Reformat1 ( FIGURE 10.29 ) .
Figure 10.29. The Reformat node determines the resolution of Scan-
lineRender1's output.
The resolution of the reflection map is now correct. Using a different aspect
ratio would have eventually resulted in a squashed or stretched looking reflection
( FIGURE 10.30 ) .
Figure 10.30. The correctly proportioned panorama is now ready.