TOP to CHOP negative values

Is it possible to get the TOP to CHOP to output raw float values (including negative values)? I have a pixel shader that’s doing some computations which include coordinates in a few color buffers. I’d like to be able to extract the contents of those buffers into CHOPs, but the TOP to CHOP is clamping negative values to 0.

What is the pixel format of the TOP you are rendering into? They should output floating point values if the pixel format is a floating point format.