The F707 has an IR viewfinder option, which means that in the dark, you can choose to look at the IR spectrum which, when someone is wearing thin clothes, you may not be able to see but just see underneath. I don't know if the Sony gives you the option to capture the IR spectrum though.
I'm almost afraid to ask what you plan to do if it could capture the IR spectrum.
it can shoot though thin clothes, but you have to but an extra len first. under normal TR function, you can only see though a little bit of it, but with this len, you will have a full colour view....but ....what is your pupose?
The lens called VR-2