Hi,
Planned to buy Alpy 200 to start my spectroscopy journey, however, a bit tight on budget. Would like to have someone here to advice on the required gear for a complete and minimal function (minus option).
Alpy 200 Spectroscope - https://www.shelyak....oscope/?lang=en
Guiding module - https://www.shelyak....e-alpy/?lang=en
BTW, if no calibration module, is it still be able to complete the object spectrum recording?
Here my current gear:
Nexstar 5se with f/6.3 reducer
ZWO ASI 120MM
ZWO ASI 533MC
Hi,
There are lots of things to consider in buying a spectroscope. I have some experience, but Robin and others know much more than I.
Let me start by saying that STARTING spectroscopy on faint targets is a TERRIBLE IDEA.
Start with bright targets. Start with lots of targets. The more spectra you take the better you will become. If you have an SA200, take lots and lots of spectra with that. Increase the distance between the grating and the camera to increase resolution to see more lines - try this for type A stars and see how many Balmer lines you can see. Decrease the distance between the grating and the camera to decrease resolution but to see fainter targets - try this for Wolf Rayet stars, carbon stars, maybe planetary nebulae.
Personally, in general, I think it's more helpful most of the time for most people to see more spectroscopic details (more lines) rather than less. It allows you to discern more differences between targets.
As for minimal setup. I have a Borg 55FL (55 mm refractor) and an Alpy 600 = no guiding module and no calibration model, operating in slitless mode. ASI178MM camera. The mount is a skyguider pro. I use a 35 mm Canon camera lens to find my targets (you will need some kind of guidscope probably -- trying to slew to targets with the ALpy guiding camera could be difficult). I wouldn't recommend this setup, certainly not for starting. But I can set it up in a matter of minutes. I can take spectra of lots of bright targets. With small pixel size and star image (f/ 4.5) and great seeing means I get pretty good resolution. I got a bunch of spectra of stars in M45 (the Pleiades) in one night. My point is to show what can be done with minimal setup and why Alpy 600 affords good resolution for beginners. (Eta Tau red, reference blue)
In addition to Balmer lines of hydrogen there are helium and metal lines here. Also note the wide balmer lines of Pleione (28 Tau) due to it's fast rotation and high i sini value (we see it close to equator-on). This is very rewarding spectroscopy. There's a lot to see.
If you want to submit to databases then the guiding and calibration modules are probably necessasry
Edited by Organic Astrochemist, 19 January 2025 - 09:13 PM.