(meteorobs) Meteor Spectra

[Ed Majden]

Mark:
	The more g/mm the larger the spectral dispersion you will have.  I 
recommend a 600g/mm grating blazed for the visual region, around 550 
nm.  Such gratings will create a spectrum of the zero order image on 
both sides.  The intensity will be brighter in the blaze direction.  
The cameras center line is shifted when adding a grating.  You will see 
this when you put your grating on the lens.  A bright meteor outside 
the field of the camera may record a spectrum.  You have to watch out 
for stray lights as they will do the same thing.  I suggest you go to 
the IMO sight and down load the Photographic Handbook.  Chapter 3 is on 
Meteor Spectroscopy and will explain all of this.  This can be found 
here:

http://www.imo.net/photo/handbook

Hope this helps:
Ed


On 15-Aug-07, at 2:22 PM, mark_vornhusen wrote:

> Ed:
> Thanks for your help. This is a 50mm intensifier, so 120mm lens
> works just fine for me and I noticed 120mm gives me better image
> quality than 80mm lens. Does the g/mm value have an influence on the
> distance of the spectra to the meteor? My fear is that the spectra
> is often outside the field of view.
>
> I have an example video taken with 120mm lens here:
> http://www.youtube.com/watch?v=6XTBrYWrey0
>
>
> Mark