LowSpec 600 and 1800 grating comparison

[drjolo]

I have been using LowSpec already some time with 600 lpmm grating (from Edmund Optics). Recently I have purchased 1800 lpmm holographic grating from Thorlabs to be able to analyze deeper Ha lines. This grating has pretty large dispersion, so I needed to saw a little (about 1mm) of the grating holder to be able to reach the very red end of the spectrum. Other than that all works fine, and here are first results compared to the ones captured with the same LowSpec device an 600 lpmm grating.

Sun Mg triplet at with 600 and 1800 grating and different slits

Sun Na doublet with 600 and 1800 grating and different slits

Aldebaran spectra around H alpha line, 30um slit

17 Tauri spectra around H alpha line, 30um slit

Other equipment used: Meade ACF 10" f/10, Evostar ED72 + IMX224 as electronic viewfinder, ASI290MM as guide camera, EQ6 mount. Suburban sky. 

[Merlin66]

Onwards and Upwards!!

Well done, keep the good work coming.

 

[ejp1684]

Encouraging. I'm still waiting for a clear night (or even an hour or two!) to check out my Lowspec 3. Thanks for this comparison, I hope to get an 1800 grating when I get everything working again. Not much sunshine here, either.

Eric.

Edited March 19, 2020 by ejp1684

[drjolo]

Thanks!

20 hours ago, ejp1684 said:

Not much sunshine here, either.

You don't need a direct sunlight to take Sun spectrum - it is enough to point the spectroscope inlet to the cloudy sky. I took my first spectra ever this way  It was captured with IMX224 camera

[ejp1684]

53 minutes ago, drjolo said:

You don't need a direct sunlight to take Sun spectrum - it is enough to point the spectroscope inlet to the cloudy sky. I took my first spectra ever this way  It was captured with IMX224 camera

 

Thanks for this. But my main task is to check that the guide scope works. I had a bit of trouble with alignment on the last version of Lowspec I made.

Eric.