Low Resolution Stellar Spectroscopy with Shelyak : Alpy 600 Slit-Spectrograph
Jim Ferreira, Livermore CA  bakerst@comcast.net

Alpy 600, SV80S

Alpy 600, C925, Moonlite focuser

[February 2014]  Below are first spectra with the Alpy 600 using a Stellarvue SV80S APO @ f/6 and The Imaging Source DMK41 video camera.  Results with the DMK41 camera have been most rewarding.  The Sony ICX205AL 1/2" format CCD with 4.65u square pixels, 1280x960 resolution is well suited for use with the Alpy 600, allowing spectra to be recorded between 3800-6800 Angstrom
.  So far, the DMK41 camera being non-cooled and only an 8 bit imaging system has not been a hindrance recording spectra of stars down to 8th magnitude.  Recording and combining 10 to 30 frames, and using a dark frame in post processing seems to keep noise down to reasonable levels.

[March 2014]  An Atik 420M monochrome CCD camera is the latest addition to the system.  The 420M uses a Sony ICX274 CCD with 1620 x 1220 resolution, utilizing 4.4u x 4.4u pixels so overall resolution is a little better than with the DMK41.  The 420M will produce images with far better s/n with cooling to -25 degree ambient and 16 bit image depth.

[May 2014] Acquired an Alpy 600 off-axis guiding unit and using it with a DMK41 video camera.  A very effective piece of equipment for centering the star on the spectroscope's slit, and with all but the brightest stars, I can guide on the star I am recording.  I will now also be able to use the Alpy 600 on my C9 SCT for fainter objects such as galactic-novae and super-novae, along with fainter variable stars.

[2017] The addition of a motor driven Moonlite Crayford focuser to the C9 that can incorporate the Celestron 0.63x focal reducer in the drawtube has improved fine focus of spectra while the scope is guiding. 

Purchased the Alpy 600 spectrograph and Alpy off-axis guider from Woodland Hills Camera & Telescopes, @ telescopes.net   Friendly folks, excellent service.  "Yeah, I'd buy a used car from them."
Alpy 600 spectrograph with Alpy off-axis guider with DMK41 video and Atik 420 mono CCD camera,
Stellarvue SV80S f/6, 80mm guidescope with DMK21 video, Losmandy GM8 mount

Alpy 600 spectrograph with Alpy off-axis guider with DMK41 video and Atik 420 mono CCD camera,
Celestron C9.25 SCT with 0.6x reducer in Moonlite motorized focuser, Losmandy G11 mount.






NOVA SGR 2015 #2






First efforts with the Alpy 600 spectrograph, 2014 [below]

Wolf-Rayet WR6, Alpy 600, SV80S, Atik ATK16
Above, spectra of Wolf-Rayet star EZ Cma with Alpy 600 spectrograph using a SV80S and Atik ATK16 CCD camera.
Below is a similar Wolf-Rayet star, WR141, recorded with a Star Analyzer SA100, 100 lines/mm grating, using same
scope and camera.  The increase in spectral
resolution is clearly apparent in the Alpy 600 spectra above.
Wolf-Rayet star WR141

Alpha Orionis, Alpy 600 spectra
Alpha Orionis "Betelgeuse", Alpy 600, SV80S, DMK41 video

Beta Aurigae, Alpy 600 spectra
Beta Auriga, Alpy 600, SV80S, DMK41 video

Orion Nebula Spectra, Alpy 600
Spectra of Orion Nebula core next to Trapezium star groug, Alpy 600, SV80S, DMK41 video

Solar spectra, Alpy 600
Solar spectra, Alpy 600, SV80S, DMK41 video

Zeta Tauri, spectra comparison, Feb.-Mar. 2014, Alpy
Be star Zeta Tauri, Alpy 600, SV80S, DMK41 video

Bright Stars of Orion, Alpy 600 spectra
Spectroscopy of brightest stars in Orion constellation, Alpy 600, 80mm f/6 APO, DMK41

28 Tau, Na I and H-alpha spectra, Alpy 600
Be star 28 Tau, Pleiades, Alpy 600 spectrograph / SV80S @ f/6 / DMK41 video

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