Re: [ATM] Are these kits good?

["Richard F.L.R. Snashall" <rflrs@rcn.com>]

Richard F.L.R. Snashall wrote:

>momsoldguns@qwest.net wrote:
>
>
>>Richard, 
>>
>>I had a couple of questions, and there were a couple of sticky points in
>>fabrication for me ... I'm sure that yours are probably more optically
>>oriented than mine ... I thought he went a little over the board on
>>measuring the radius of r-3 though, and I thought he should have spent more
>>time on test plates ... what did you see? 
>>
>>Coyoté
>>
>>
>I took his discussion to mean that this design was better since
>it was the canonical CF correction.  I don't consider that as
>an absolute.  (The design is not quite the canonical CF
>correction -- that design is visually even worse.)
>
For those wanting to follow in Mr. Parker's footsteps, an alternative
design with the correction shifted slightly (4.4 nm) toward the blue:

Surf      Radius    Thickness     Glass    Diameter
 STO    Infinity  -0.08623005                     6
   2     52.2291        0.627     N-BK7        6.12
   3    -32.0769        0.288                  6.12
   4    -32.0769        0.444        F4        6.12
   5    -145.875     88.78563                  6.12
   6   -32.20869       0.0069              1.579836
 IMA   -32.20869                           1.579497

No, the C and F lines don't cross in the aperture...
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