I think that anyone can create an organization on GitHub; then you just add teams/contributors and packages. The hard part is the social one, getting folks to contribute their packages. But orgs have worked out pretty well in general, so I think it might be merited.
Sounds like a good idea. As Felix wrote, we are currently active creating a few tools for microscopy use in Julia. In addition to Felix’s list, PSFs.jl is also coming up. To collect useful packages under one heading seems good to me.
It might be also worth to think about using the JuliaOptics Org (which has been used it the past and has currently different ownership) instead of focusing too much on microscopy?
I hear you. Maybe this is getting into the weeds, but I think the green lens should be concave, in order to turn converging rays into parallel, kind of an inversion of the first, purple, lens. Probably best to run it by an optics exert to make sure it all makes sense.
As usually there is a conflict between being technically precise and having an expressive graphical design. Real compound lens are never symmetric, I beleive (I’m not an optics expert), and nowadays pretty complex (see the post by BioTurboNick above), whereas the logo should preferably be simple enough and somehow symmetric (I’m even less a graphics expert).
Maybe something like this? That wouldn’t be completely physically wrong, and simple enough. Note different curvature of the inner interfaces vs. outer surfaces.