The thing is, if it "could" be done, it still "can" be done. How much and how fast is the thing. When this little hobby started out, everyone was an amateur. As far as shutters go, any watch maker worth his salt can make one. Even with as meager a machinists' background as mine, a person could make one. Could probably pump out as many as 6-8 per year. To keep it simple enough to make easily, it would only have a top speed of about 1/150 sec, but that's probably more than you'd need if you were making your own emulsion.