My CT volume is 12-bits short data, but the negative values can be simply ignored.

I want ask what's the difference between:

glTexImage3D(GL_TEXTURE_3D, 0, GL_LUMINANCE, imgWidth_, imgHeight_, imgSlice_, 0, GL_LUMINANCE, GL_UNSIGNED_SHORT, volume_);

and

glTexImage3D(GL_TEXTURE_3D, 0, GL_LUMINANCE, imgWidth_, imgHeight_, imgSlice_, 0, GL_LUMINANCE, GL_SHORT, volume_);

which one is better for creating 3d texture? and when I use GLSL doing the sampling, should I times 16.0 to let the 12-bits value normalized to (0.0 - 1.0).

Thanks a lot!