You can usually improve the image of these HDMI devices with an HDMI scanline generator.
My current Jaguar setup consists of a SCART to HDMI converter with HDMI scanline generator. I've used similar devices with SCART to VGA output for other consoles. I just recently came across this HDMI specific device.
The scanline generator down-scales to a 4:3 aspect ratio of (1024 x 768), I'm using a 50" plasma TV. The image does not center but displays from left to right with about 1/4 of the screen's far right as a blank screen.
These are available from eBay (least expensive - from China) and Amazon.
There is a good review of the device on YouTube (7 minutes in length):
I took these pics off my TV .... My apologies as I do not have a video capture card. First pic is native HDMI displayed, second pic has scanlines.
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