Hi Bostjan,

Which telescope are you referring to, LX200 ??"

Berto

Hi Paulo!

I have been using the Lumicon f/6.3 Giant Focal Reducing lens over the past few
years and I have tried many possible CCD setups with it. I noticed the
following:
- the image is nicely sharp at f/6.3
- the sharpness decreases as you increase the distance between the lens and the
focal reducer.
Loss of sharpness is not severe down to about f/5-f/5.5
- below f/4.5 there is VERY noticeable sharpness loss, ending in
VERY POOR IMAGE QUALITY at f/3.3
- also, as you move the CCD, you have to move also the guiding eyepyece (or CCD)
to achieve focus. At f/3.3 the distance from the off axis guider is
considerable, requiring an extension tube and inducing possible flexibilities
(causing image drift during exposure etc.)

I don't know if the Meade reducer behaves somewhat differently, but I do NOT
reccomend using f/6.3 reducer at f/3.3 - it has been designed to work at f/6.3
and that's where it works fine.

Hope that helps.

Best Regards,

Bostjan



----- Original Message -----
Sent: Sunday, August 26, 2001 10:43 PM
Subject: [M]: Focal Reducer Strangeness...



I have both F3.3 and F6.3 Meade focal reducers. Using my CCD camera
since some three months with F3.3, recently I ve observed that if you
use the F6.3 reducer and an off-axis guider (Orion Ultraguider), with an
additional extension of some 1 inch ( That cames with F3.3 reducer) you
got a F3 assembly !!!! with advantage of a guiding eyepiece or
autoguider !!!

It seems that F3.3 reducer has no role if you have a small CCD like mine
(HX516).

I ve missed something here or I can sell the F3.3 unit???

Paulo

View index by [date] [author] [subject]
Previous message: [M]: green vs red lighting to preserve night vision, Andy Wallace
Next message: [M]: Re: RE: Focal Reducer Strangeness..., Bostjan
Next message in thread: [M]: Re: RE: Focal Reducer Strangeness..., Bostjan
Previous message in thread: [M]: RE: Focal Reducer Strangeness..., Paulo Cacella