Recommended
Retrocombs uses ClonerAlliance Box Pro
Grubi’s thread where he made use of a SCART+HDMI (480i/576i) to HDMI (720p/1080p) convertor to upscale to 1080p and connect to his ATEM mini Extreme ISO (which can do aspect ratio conversion)
Lydon makes use of a cheap VGA-to-HDMI convertor (to upscale to 1080p) which he then connnects to his ATEM mini pro ISO
AmokPhaze101 recommends this HDMI Video Capture USB adapter in this thread. He said it worked fine for capturing c64 demos at 30fps. He has since moved onto a device that captures at 60fps.
Retrocogs recommands the AVerMedia GC513 Live Gamer Portable 2 Plus, this can do 1080p60, doesn’t drop frames and is silky smooth.
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Not Recommended
M3wP and Gurce made use of this HDMI-capture device:
WARNING: We both observe a strange ‘hissing/noise' sound from it when the right/left volumes weren’t equal. E.g. type
VOL 15,0as demonstrated in this video