Hi everyone!
I've been browsing the spectroscopy section of this website now and found a lot of great info!
After following the links included in the section, I found some other tools that I was wondering if they could be used rather than buying a dedicated spectrograph... (Price is... yikes...)
These tools were the SA-100 Grating, and the RSpec software sold by the same company.
I already have a few telescopes that could be used for this, and two tracking mounts. One being an AVX.
Is it really possible that all I need is a $200 grating and a $110 software? I do see that ISIS appears to be recommended directly in the manuals provided by AAVSO... but can it be used with the SA-100?
It's also mentioned in the intro that, "We reiterate that what follows are the data necessary to produce a fully processed spectrum, but this does not constitute the SpecDB submission requirements..." Does the intro meet requirements to submit to AVSpec?
How much further processing needs to be done in order to submit a spectra?
It's also not clear to me if we are submitting an image/FITS of the spectra or a graph of said spectra.
Any additional information is greatly appreciated before I start spending money on the gear.
-Chris
Hi Chris,
I was in the same position as you 15 years ago so I developed the Star Analyser mainly as a low cost way for people to try spectroscopy without a big financial outlay. (It is manufactured by Paton Hawksley in the UK and sold in the US by Tom Field who wrote the RSpec software). It is possible to do some useful science with it but it is very low resolution and difficult to calibrate accurately so you have to pick your subject. For example it can be used to make an initial classification of transients like novae,dwarf novae etc. I have also used it to detect and analyse fast transients in T Tauri stars (top item on this page)
http://www.threehillsobservatory.co.uk/astro/spectroscopy_10.htm
and Andrew Smith is using the same technique to pickup fast flares in flare stars.
https://stargazerslounge.com/topic/345624-first-second-flare/
The inage of the spectrum is digitised and calibrated before being submitted as a 1D fits file (a list of intensities against wavelength)
ISIS can be used to process Star Analyser spectra but for a beginner RSpec or the similar software Visual Spec
http://www.astrosurf.com/vdesnoux/
is probably easier. You can see on my website how this is done using a combination of ISIS and Visual Spec in the presentation entitled "Low Resolution spectroscopy (Star Analyser)" on this page
http://www.threehillsobservatory.co.uk/astro/spectroscopy_10.htm
and there are many other examples of Star Analyser spectra elsewhere on my website.
Cheers
Robin
Note that although good fun to use in its own right, for more serious work the Star Analyser is more a stepping stone to the use of more sophisticated instruments if the bug bites as it did for me. I now have three other spectrographs (LHIRES,ALPY600, modified ALPY200) each filling a different niche
Cheers
Robin
Hi Robin!
Thanks for the quick reply! Sounds like the SA-100 would be a good start.
When you say low resolution, would the only good targets be new transients and only at the beginning for initial info gathering? Outside of that, it would be an education tool? Or could it still be useful on other objects as well long term or on a continuing time scale? (T Tauri type objects). My other concern here is that if these are used for low resolution spectroscopy, is it still possible to meet AVSpec requirements on the initial test image before we are allowed to submit as desired?
Does RSpec have the ability to create 1D FITS files or do you recommend that I follow your "Low Resolution Spectroscopy) presentation?
I could definitely end up using one as an AAVSO ambassador or NASA/JPL ambassador at one of my events that I hold throughout the year as well.
Using a grating, SA100/ 200 is "Spectroscopy 101".
Depending on your set-up, whether used with a camera lens or in the telescope, the results you obtain, even at low resolution will allow you to start your journey in spectroscopy.
The processing of a spectral image to a 1D fits file is relatively straightforward and the mentioned software ( as well as BASS Project https://groups.io/g/BassSpectro ) will get you started.
http://www.astronomicalspectroscopy.com/start.html
Ken
Thanks for the reply, Ken!
I plan on using a telescope for my measurements.
Based off of cost alone, I think I'll be in the low-resolution phase for a while.
Have a look at the current generation of 3D printed spectrographs......
https://groups.io/g/astronomicalspectroscopy/search?q=%233Dprinted_spectrograph&ct=1
Those are impressive!
I do have a few people I could pay to build the body then piece the rest together. :)