The ExpoDisc (4x5.65") waist level lens is clean and working

lens is clean and working well

a pair of close-up attachments

The Lomography New Petzval 58mm f1

front and rear caps

new foam gasket

The ExpoDisc (4x5.65") waist level lens is clean and workingThis particular Expodisc is not a disc it's a big 4x5. 65" slab designed to slip into matteboxes but it works the same as the classic. Basically, it's a specialized flat diffuser designed to facilitate setting custom white balance. Rather than hauling around a gray card, or trying to find a plain white surface, or hoping that your camera guesses correctly, you can toss this in front of your lens and lock in an accurate custom white balance in seconds.