Sony has told World+Dog that its labs are working on an entry-level pro camcorder with interchangeable lenses.

Provisionally dubbed the dubbed the "NXCAM", the HD camcorder will come with a sensor that's equivalent to a Super 35mm frame and Sony's E-Mount lens system as used by its consumer-oriented Nex compact cameras and camcorders.

A-Mount lenses - the type used by Sony's Alpha digital SLR cameras - can be used too, albeit mediated by an A-to-E adaptor.

Sony said the NXCAM will record in the AVCHD and MPEG 4 AVC/H.264 formats at up to 1080p.

Here's a vid of the prototype:

There's no word on when the NXCAM will debut, but Sony's unlikely to hang around now it has given its rivals such a public heads-up. Given the professional nature of the gadget, how about a launch at April 2011's US-centric National Association of Broadcasters (NAB) show? ®