[jcampbell1]

The red camera has no shutter. It just reads from the sensor. It can set the exposure length to anything less than the frame rate minus the time to read the sensor. So at 48fps, the exposure can be 1/48 second minus the time to read the sensor, which is approximately equal to 1/48th of a second.

A film camera cannot do this because there must be time to move the film around, and so the standard design creates 24 frames per second, with 1/48th of a second to physically move the film, and 1/48th of a second to expose the film. Of course you could expose the film for less than 1/48th of a second, but that would create the problem you originally mentioned.

My point is that the RED camera at 48fps with the "shutter" always open, you have the same exposure length (and motion blur) as a standard film camera.

[excuse-me]

it has a shutter - it's simply electronic. The exposure is the time between the pixel reset and the readout. On the EPIC chip there is a full frame reset and a per row reset. On some scientific chips it's possible to reset an individual pixel immediately before reading it, it's even possible to read a pixel multiple times without resetting it so you can get multiple exposure times in the same pixel in the same frame!