Calibration Confusion

[johnb]

So using my SA100 I can now capture a spectrum (just) but the processing I find confusing. I use Rspec and there are reference files and so on and then there is instrument response etc. Rspec does have videos but I'm still not really with it. Is there a standard workflow with detailed steps ?

Also once you have calibrated for a certain star type can that be a reference or do you need to repeat each time ?

Regards

John B

[the rev]

I started with vega, which I then followed the video to create an instrument response, which I use after calibrating each of my spectra. I divide the instrument response with the calibrated spectrum and this corrects for any things in my camera.

I use rspec and had the video playing as I worked through each step. If you play them in the order given they will work through each step easily.

Kate

[johnb]

So the Instrument response is a one off activity ?

John B

[the rev]

From what I understand. When I started it was guested I used vega to create my instrument response. Since then I have heard others talk about needing to use a different star for instrument response if the stars they are studying are more than a certain distance blow vega, but they could explain that better than me.

[Merlin66]

The standard star Vega provides a good, easy set of Balmer lines to use as reference wavelengths. Once you have calibrated your instrument the instrument response curve can generally be used to correct any other spectra obtained with exactlt the same set-up.

Atmospheric conditions and altitude of the target star can sometimes affect the results, but at this stage, they will be minimal.

It's a good habit to obtain a spectrum from a standard star each night to ensure the set-up is OK and this can also be used to re-verify focus etc.

Hope this helps.

[the rev]

Question Merlin - is a standard star an A class star, or can it be any?

[Merlin66]

Type A stars are easier to use due to the well defined Balmer series. M type are far more dificult to interpretate.