On 3/16/2018 11:05 AM, Jan Steinman via olympus wrote:
From: JOHN DUGGAN <john.duggan10@xxxxxxxxxxxxxx>
Does anyone have info on Leiberkulm reflectors regarding the radius of the
reflecting surface. It should be straightforward to machine? in white plastic
or aluminium given this dimension. failing this I will experiment with the
curved bases of drinks cans or bottled gas containers etc.
This guy has done all the math and will 3-D print them for you for under ten
bucks:
Description of the design process and results:
https://thebilder.wordpress.com/2014/03/25/first-tests-of-3d-printed-lieberkuhn-reflectors/
Order page:
https://www.shapeways.com/product/R9NYJJUE6/lieberkuhn-reflector-49mm-lens-diameter-f-20mm?optionId=57933798&li=marketplace
I've ordered one.
Damn evilBay sale tapped me out for a while, but I’m seriously considering
getting one of these, rather than cobbling something together.
He has put a lot of work into getting the proper parabolic shape and focal
length.
But I think he has worked on the assumption that they are mounted on filter threads a couple of mm in front of the lens
FE, not ~17 mm behind. A 20 mm or so difference is huge for any such calculation. I'll see how it works when it gets here.
Better would be to duplicate the Oly ones on a 3D printer.
Reflective Moose
He even sells a set of four for Canon 62mm thread-size macro lens, for use at four
different reproduction ratios. But I’m thinking just about any old bit of white
stuff you can put there will work Pretty Durn Well(TM).
Jan
--
What if the Hokey Pokey *IS* what it's all about?
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