Re: ATM Building a spectrohelioscope

[Antonio de Ugarte Postigo <ugarte@mad.servicom.es>]

At 20:48 29/06/98 +0200, you wrote:
>
>Hello everybody,
>
>First, as a new user of this list,  let me introduce myself: I'm a french
>student at an engineering school, and an active builder of telescopes
>(several Newtons, 2 Schmidt cameras, ...).
>I plan to build a spectrohelioscope using a grating (similar to the one
>described in Amateur Telescope Making Book One Part IX), but I'd like to
>build a transportable one (not in a building like in the book). I'd like to
>know if somebody has built such a spectrohelioscope and where I could find
>informations on this subject (article, web page, ...).
>Thank you,
>
>       Sylvain Rondi.
>
Hello Sylvain,
        first of all wellcome to the list, there are many people
here with a very wide knowledge from who I am learning a lot, so I'm
sure you'll find all the information you need for your projects.
        I  built a few years ago a solar spectroscope based on a 
difraction grating that I bought from Edmund Scientific. It's one of the 
simplest design you can get. I get a resolution of about 1 or 2 Angstroms
in the second order when I manage to get the slit correctly placed. Since 
then I have thought of making a perfected one, but I never had the 
time nor the money to make a really good one. Mine is a box with a slit,
a colimating lens, the difraction grating mounted on a rotationary device
and a focusing lens. It can be used alone to see the spectra of a light source
or it can be mounted on a telescope to see the spectra of a small portion 
of the Sun. In this way I've been able to see He emission lines in the 
cromosfere of the Sun (at the limb). If you need any more info on any
details of my design I'd be very happy to help you.

I don't know about the design you are talking about, but I am really 
interested in knowing more about it. If you could describe what it is 
like or even send me a transcription of it I would really apreciate it.

Antonio De Ugarte Postigo
Boadilla del Monte (Madrid)
SPAIN
ugarte@mad.servicom.es