5 replies to this topic

[kaicyung]

I just produced a YouTube video on how to collect and analyze star spectra with Seestar and a cheap kit. Enjoy.

 

Album: Spectroscopy

1 images

0 comments

 

https://youtu.be/aY4...-uvV--HwDl-qcq7

 

 

 

 

[robin_astro]

That grating must be extremely inefficient with a lot of light wasted in that very bright zero order and the rest split between all those spectra.  (how much light actually gets used? I would guess only a few percent.)  An efficient blazed grating used with a simple camera would work much  better. 

http://www.threehill...troscopy_11.htm

 

 

Cheers

Robin

Edited by robin_astro, 02 February 2025 - 08:41 AM.

[robin_astro]

Covering only half the aperture with the grating loses even more light. I dont understand why you would want to do that. Even with the grating covering the whole aperture, the zero order images of the stars are visible and can be used to plate solve, align and stack.

 

Cheers

Robin

[kaicyung]

That grating must be extremely inefficient with a lot of light wasted in that very bright zero order and the rest split between all those spectra.  (how much light actually gets used? I would guess only a few percent.)  An efficient blazed grating used with a simple camera would work much  better. 

http://www.threehill...troscopy_11.htm

 

 

Cheers

Robin

This grating is really a gateway to the world of stellar spectroscopy for the masses. It is no mean the best grating one can get. Instead, I can source is cheaply and offer it to the novice and the curious with very little upfront cost. It is therefore a good introductory tool for casual users with inexpensive scopes like the Seestars. As you know, we have captured and analyzed much better quality spectra last year, and my hope is that this simple grating will get many more people interested and explore further what this branch of citizen science can offer.

[robin_astro]

You should be realistic though and make it clear in your video what people will actually be able to achieve with this setup. You suggest various measurements which can be done using spectroscopy, showing a spectrum from the SDSS taken at much higher resolution but show no actual examples of stellar spectra taken with this setup.

[Airship]

I have been using my Seestars for photometry for nearly a year with excellent results. Testing them to take spectra using my SA100 has been on my shortlist for a long time. Should be fun!