Re: [APML]: Thinking about a Ritchey-Chretien

["Tom Krajci" <krajcit@det5wg57.barksdale.af.mil>]

> From:          efernan@df1.telmex.net.mx (Eduardo Fernandez)

> ... I am looking forward to buy a 10" or 12.5"
> 
> Ritchey-Chretien but I have started to read stuff about them and
> astigmatism and field curvature are a problem . I would like to know your opinions 
> about this scope & if it makes a supberb astrophoto instrument .

For larger aperture systems it's hard to beat an R-C design.  Every 
system. . .unless it is specifically designed for astrophotography. . 
.will have field curvature.  For an R-C a custom field 
flattener/corrector lens near the focal plane can help keep tighter 
star images over a larger piece of flat film.

Chuck Vaughn now uses a corrector/field flattener on his R-C (I 
think).

Tom Krajci

Capt Tom Krajci
B-52 Intelligence Officer
"In God we trust, all others we monitor!"
http://spur.barksdale.af.mil