If a Scarlet is in your price range and you like the HDSLR "look" then you might also consider the Canon C300. It's less expensive than the Scarlet, when you've added all the necessary extras to get through a day of shooting. The testing I've done on mine so far shows that the onboard CF card MXF 4.2.2 recording gives an excellent chroma key.
Gone also are the moiree, aliasing, 12 minute per shot record limit, and it records full PCM audio.
Cinematographer, Steadicam Operator, Final Cut Pro Post Production.
http://philming.com.au
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