I have 1080p square pixel footage from my canon 600D (t3i) which i need to put onto a DVD. I plan to do this using adobe encore and my composition is in after effects. I understand that to do this is I need to render the footage in a composition with the correct parameters for dvd. I'm currently following video copilots tutorial here: http://www.videocopilot.net/tutorial/dvd_authoring/ although I'm slightly confused. All the NTSC presets don't have square pixels and yet my footage is square pixels so when i put it into a NTSC comp it gets stretched and looks horrible. My question is, as long as i have the correct height and width in the composition, can i change the pixel aspect ratio to square pixels to suit my footage? Alternatively I thought I could use the PAL widescreen square pixel preset however my footage's frame rate is 23.98 (or whatever it is) and the frame rate on that is 25. I guess overall i just need to know whether you only need the correct height and width settings for DVD as opposed to the default pixel aspect ratio and framerate.
The pixel aspect ratio of your composition should match the destination device's pixel aspect ratio. So the non-square pixel aspect ratio in your AE composition is not only expected but required for proper output to DVD.
If you'd like a rough preview of how the video will look on DVD then you can enable the pixel aspect ratio preview switch at the bottom left of the composition viewer.