How can I change the Pixel Aspect ratio of my recording?

[TidusWulf]

I'm trying to capture some VHS tapes which have a pixel aspect ratio of 0.9. So even though the source footage is 720x480, the canvas dimensions should be 4:3. From what I can tell, OBS will only let me record 720x480 at an aspect ratio is 3:2, which means square pixels. It causes my footage to look slightly stretched out in one direction.

The hardware I'm using is Elgato Screen Capture. Elgato's own software properly records at 0.9, but the bitrate is really low, and there doesn't seem to be a way to bring it higher.

 

[koala]

There is a large variety of choices where there are (usually configurable) resolutions and influence the aspect ratio in OBS.

• the source (VHS) has its own aspect ratio
• in the properties of the capture device, you can set various custom resolutions
• in Settings→Video→Base resolution you can set the resolution of the canvas where the capture device output is painted on
• in Settings→Video→Output resolution you can set the resolution of the created video

You want a video with quadratic pixels, because that's the only kind of video OBS is able to create.
What you now want to do is to distort the video to create square pixels from the non square pixels of VHS recordings.

I recommend you do this with the output resolution.
Let the capture device capture the native resolution of your VHS, for example 720x480. Also set the base resolution the same.
As output resolution, set a resolution with 4:3 aspect ratio, for example 720x540. Or 640x480. What you like. By converting the canvas to the output resolution, the pixels will be stretched accordingly.

 

[AaronD]

I recommend you do this with the output resolution.
Let the capture device capture the native resolution of your VHS, for example 720x480. Also set the base resolution the same.
As output resolution, set a resolution with 4:3 aspect ratio, for example 720x540. Or 640x480. What you like. By converting the canvas to the output resolution, the pixels will be stretched accordingly.

If you do it this way, don't panic when OBS shows you the stretched-out version of the video. You're looking at (and working with) the canvas, not the output. If you set the output as above, then the recording will be right, despite looking wrong in OBS.