Re: ATM Beginners questions

[Mel Bartels <mbartels@efn.org>]

Ross_Dawson@county.com.au wrote:

> 1.  I am thinking about constructing a 10" f/5 Newtonian reflector.
> Is
> this a suitable design for deep space CCD photography.  Would a lower
> ratio
> be better for the CCD as this would make the scope shorter and more
> portable (also easier for the kids to see the eyepiece)

A 10" f/5 would be a great CCD scope, particularly suited to today's CCD
chip sizes and pixel sizes.  You could go as fast as f/4.


> 2.  What about eyepieces for the above scope both for the CCD (does it
> need
> one?) and for people?

The CCD does not need an eyepiece - it goes in place of the eyepiece,
though if you want planetary CCD imagines, you will want to project an
enlarged image into the CCD, sometimes done with an eyepiece.


> 3.  I have read on the web that motorised Dobson mounts are not
> suitable
> for use with a CCD, but then I have seen pictures captured using just
> such
> a setup (ala Mel Bartels).  I haven't been able to acertain the reason
> why

Don't believe everything you hear on the net <smile>!  On the net,
everyone's an expert, so you have to be really careful who you trust for
accurate information.  The atm list is the most accurate source of
information on telescope making there is on the net.  If anyone should
post something questionable here, it will be quickly pointed out.

There are great images coming from amateur computerized altaz scopes
now, just as there has been great images coming from professional altaz
scopes for many years.

> 5.  Are there any good sources/descriptions on Mirror construction and
>
> testing on the Web.  I'm trying to chase up copies of Berry and
> Texereau
> but the cost of books here in Australia tends to be astranomical
> (pardon
> the pun).  So if I can glean as much info from the internet I can save
> my
> self probably about $150.

My webpage on large thin mirror making might serve as an introduction,
as techniques used for large mirrors are basically extensions of the
techniques used on smaller stuff.

--
Clear skies, Mel Bartels    Programmer/Analyst, amateur astronomer
Eugene, Oregon, USA         homepage: http://www.efn.org/~mbartels
mailto:mbartels@efn.org     atm, atm-digest list-owner
Motorize A Dob: http://zebu.uoregon.edu/~mbartels/altaz/altaz.html