HDR without shaders - It can be done the lamers way

[tanffn]

So, is it possible to do HDR without shaders?

Why not?
Read Delfi's post.

Edit - I just remembered a few years ago I made a program that presented 12bit grayscale scan (NDT scanner we developed) to the screen (8 bit). With bias and gain you can ‘pen’ your intrest view => you have 12bit of data but only 8bit of data displayed.

Not your typical HDR in a sense that you might imagine it but HDR non the less.