Re: [ATM] Meade 'Fesses up

["vladimir sacek" <vlad@copper.net>]

Richard F.L.R. Snashall wrote:

> One bit of note here: From the appearance on the website, Meade optimizes
> to the d-line, not the e-line; from what I've seen of single glass SCs, 
> that
> tiny spot size occurs at only one wavelength.

That is to expect; the formula assumes no blur at the optimized wavelength, 
which is something that can't be achieved even in raytracing, let alone 
fabrication. The best I got for this system in that respect is about 3-4 
microns (and still hairy) blur at the optimized wavelength, which would make 
the raytracing red and blue blurs closer to 10 microns and that in violet 
closer to 20. That is on axis. Off-axis blur will be, in general, larger due 
to astigmatism and field curvature. Real-life blur sizes are likely to be 
still larger.

Vlad 


_______________________________________________
ATM mailing list http://www.atmlist.net/