Most lenses already have a standard, secure method for attaching accessories to the distal end. So why do we still put up with the infamy of squeeze-style caps that are so easily lost? Below are some iterations of my designs for threaded lens caps, designed with information on the lens filter thread standards from Wikipedia, and printed in various colors of Shapeways basic sintered plastic. They’re durable, can be colorful, and it’s possible to emboss custom text or an image on the front. Oh, and I never worry about them falling off in the bag.
Standard sizes can be bought from http://www.shapeways.com/shops/thebilder and there is a custom option for personalized text. I am planning to make some more test shots with Lieberkühn reflectors soon, so stay tuned!