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Old 23-01-2014, 08:28 PM
malclocke (Malc)
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malclocke is offline
 
Join Date: Jun 2012
Location: Christchurch, New Zealand
Posts: 183
*Finally* got to put some starlight through my L200 last night! Just working with an unmodified DSLR and no guiding to try and keep things simple initially, using a 600 l/mm grating. Slit was at around 40 microns, scope is Canterbury Astro Soc's 0.4m RCX400.

Unfortunately I totally misjudged exposure times and consequently the SNR is very low for most of my exposures.

Also my first run at reducing the data has given me a very dodgy wavelength calibration, about 10 angstrom out in the blue end. Whether this is a limitation of using the neon lamp or user error I'm not sure, I'll keep cracking at it and see where I get to.

I'm thinking of popping an energy saver bulb in the observatory and slewing towards it for a rough and ready calibration until I get something better sorted, is that feasible?

Despite all of that, there is some data in there, see attached V1369 Cen spectrum, no instrument correction applied. P cyg absorptions are visible in Hb (focus off for Ha), and velocities look good when I fudge the zero point to correct the bad calibration.
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