Yes, the Canon EOS R8 works with the Samsung PRO Plus 256GB SD — but only 4K30 IPB Standard confirmed compatible via the U3-rated SD card.
Samsung PRO Plus is UHS-I, rated UHS Speed Class 3 (U3) per Samsung's own spec page. Canon R8's manual requires only UHS Speed Class 3 for 4K30 IPB Standard. Card meets that floor -- corrected 2026-06-21, previous verdict ("UHS-I cards are blocked from 4K recording modes") was never sourced and contradicted Canon's own manual, which lists UHS-I as a compatible card type.
Conditions for compatibility
4K30 IPB Standard confirmed compatible via the U3-rated SD card -- the only 4K codec floor currently verified for this body in this database. Higher frame-rate 4K modes are not yet spec-verified here.
“29.97 fps 25.00 fps 23.98 fps IPB (Standard) UHS Speed Class 3 or higher IPB (Light) SD Speed Class 10 or higher”
Last verified:
Confidence: inferred