Blacker than black can be

I have a Rollop TLR. The film compartment has no coating on the inside, just the bare die cast finish. Googling around with no clear direction I came across this:

Vantablack | Surrey NanoSystems

It would cut out any reflected light but would make looking in detail at it difficult.

Just sayin.

Sounds promising--too bad it's not available as a consumer product yet.

I've used Protostar telescope flocking inside a number of FSU cameras, and it's very effective. Edmund Optics sells a similar flocking as well. Links below:

Protostar Telescope Making & Upgrading

Light Absorbing Black-Out Material | Edmund Optics

Here's the flocking applied inside a Lubitel TLR.

I had a Rollop a while back. I was convinced there was a light leak coming through the front when the lenses were fully extended:

Roll Up for the Rollop

I use sticky back black felt for internal flocking.