[ATM] PLOP and Kriege/Berry Mirror Cells

[Jay Kirkland <jaykirk2@compusmart.ab.ca>]

	A quick note for future reference to summarize mostly what Mark Holm has
done in the last few days re: supporting my 20" 1 5/8" mirror. 
	A Kriege/Berry 18-point cell: PV 1/24 wave, RMS 1/34.5. Marginal support?
	Jeff Anderson-Lee's 12 point "H": PV 1/34.8, RMS 1/237. Re-focus .107mm.
Very good support, says Mark Holm. Not to mention totally wicked design. 
	Mark Holm's 18 point PLOP cell: PV 1/64, RMS 1/480. Re-focus .107mm. Again
very good support.
	My own attempt at a PLOP 18 point: PV 1/64, RMS 1/488. Re-focus .107mm.
Virtually identical to Mark's, dimensions varying by only 1/5-1/10".
	My own angles-varying 27 point PLOP: PV 1/79, RMS 1/800 Re-focus .0436mm.
Way overkill? Also after numberless hours of juggling, still can't fit all
the parts dimensions given by PLOP onto the radii and angles specified by
PLOP. Off by up to 1/4". 
	My attempt at a conventional 27 point PLOP: PV 1/85, RMS 1/640, Re-focus
.0348mm. Again, way overkill? (Is overkill possible with mirror supports?)
For whatever reason, with a conventional 27, angles fixed, all the
dimensions  fit the radii and angles specified perfectly. Why couldn't I
have started here?? 
	It would seem that Kriege/Berry/Dave Chandler come close to PLOP with
larger and thicker mirrors and with cells containing more points.
Conversely, with smaller mirrors , or thinner mirrors, or fewer points, the
divergence grows greater. 
	Thanks to everyone, especially Mark Holm.

	Jay


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