Do movies have to be recorded with a hdr camera to be true hdr?

Film has high dynamic range; it's the conversion/scanning to video (or direct video) equipment that may be limited range.

Any movie originally made on 35mm or 70mm film can be re-scanned as HD, HDR.

Most use 70mm.

35mm colour film has an equivalent horizontal resolution of something like 3000 pixels. 70mm around 6000.

That puts 35mm well above 1920x1080 and not too far under 4K; 70mm is far beyond 4K.

boh............... 

the original movie is on 70mm film (a few cheap indy films are on 35mm). to become digital, each frame is scanned. there are no digital cameras involved in this process.

There's no standard definition for "hdr", so if the new digitising proces has a greater dynamic range than the original they can reasonably claim it's hdr.

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