Hello all.

I am thinking about buying a few addons for my lx200 and st7.

I was wondering if any of u could offer me some advice on these
products, because although i am an astronomer, I know very little
of backyard astronomy. (I am more a cosmologist)

These are the items I would like to buy:

-Filter for CFW-8 filterwheel.
As my scope is located in our historical observatory in the middle of
town, I get a lot of skyglow (reflection). So I thought it would be
nice to put in a UHC (Ultra high contrast) filter so that i can
improve my snr when imaging planetary nebulae. I understdand that these
UHC filters isolate the OIII and Hydrogen Balmer lines.
A friend of mine went to a local retailer, who told him that the
normal filters available for eyepieces will not fit in the CFW-8.
Which uhc filter does fit in my cfw-8?

-Focal reducer 3.3

When I first got my lx200 and st7 i noticed to my amazement, that the
st7 could only be mounted on the scope with one small screw. I found
this Highly in adequate as it was only a matter of time, before it
would fall off. I let someone at the instrument workshop here at the
uni make a adaptor ring which would enable me to securely screw the
st7 on my scope. On the first attempt it was ofcourse to long, so that
the st7 could no longer reach polares (in equatorial mounting). After
a small modification it fitted luckily. Now i screw the cfw8 directly
on the eyepiece holder.

First of all I would like to buy a 3.3 focal reducer as I live in the
netherlands which is BELOW sealevel, so the seeing is really bad
(3-8"). I though it would be wise to enlarge my pixels with a focal
reducer. Which one could I buy best for CCD imaging (st7).
Secondly as my adapter ring is custom will that focal reducer still
fit?

-Barlow

Altough the seeing is bad, i have made some nice images of jupiter by
using the 0.11 sec exposure time. (Why cant this be shorter?)
Regretfully the resolution is a tad too low for mars and satrurn, so
maybe a barlow would help out, or are ther other sollutions for my ccd
(eyepiece projection).


Hope to hear from u.


Grtz

Bjorn
As i understand every focal reducer is fixed for a certain distances
from the mirror (or is it ccd?)
--


Bjorn Heijligers Tel: 071-5155793
Rijnsburgerweg 37b 071-5275866 (Work)
2334 BG Leiden Netherlands Room:529
http://strw.leidenuniv.nl/~heyliger
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