Really Right Stuff MPR-CL II Long Nodal Slide Clamp  type_Flash Coupling The Lensbaby Velvet 56 is

The Lensbaby Velvet 56 is closer to a "real" lens than most Lensbaby products: it doesn't twist or bend

very wide on full frame

rangefinder-style mirrorless camera with a hybrid electronic/optical viewfinder

you can do multiple exposures very easily

Nikon Nikkor-Q

Really Right Stuff MPR-CL II Long Nodal Slide Clamp &nbsptype_Flash Coupling The Lensbaby Velvet 56 isThe Really Right Stuff MPR CL II Long Nodal Slide Clamp is a roughly 18cm long Arca plate with a built in right angle clamp. Designed to locate the nodal point for panoramic photography, you could use this for all sorts of other wacky nonsense too. Not sure what, but I bet you could come up with something if you thought about it long enough. In excellent condition.