For this video I specifically didn't use my DVDO to see if Dreamcast would get picked up and recorded.
The VESA (640 on 480) mode wont work with Elgato HD Capture, however that's not a design flaw it's specifically stated on the site the device wont work with that resolution.
480p (720 on 480) works without issues, since the displayed number of pixels is the same it's just squished like all 480p picuture is.
Now there is whole debate what the correct aspect ratio for the Dreamcast should be aaand honestly I don't have a clue, since some pictures like start up logos fill out the whole active area even in 480p while for the most part games have black bars on the sides.
480p picture, since it's squished actually looks sharper but whether it's "correct" is beyond me.
There will be another video showing off how the device works with DVDO and there I show off the VESA mode as well as a little comparison at the beginning so you can decide what's more or less correct.
here is a side by side comparison I put together http://i.imgur.com/PV8u5sd.jpg
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