spectro-aras.com

Thanks Robin, much appreciated!

MIke

Can someone give me the part number, either from Edmund or Thorlabs (or elsewhere) for a replacement acromatic doublet for the LHiRes III? Thanks!

Mike

It appears my SBIG remote guide head has died - so I need to replace it, my first thought is the SBIG STi guider. I have the upgraded guide port on the LHiRes III - does anyone else here use an STi guider with the updated guide port arrangement?

TIA!
Mike

Every year about this time the focus of my LHiRes deteriorates rather significantly. It is, of course, temperature related. During the summer I get nice sharp focus, skinny and symmetric emission lines from the internal Neon-Argon source. But as the temperatures fall going into autumn, the focus slo...

I have recently exchanged a couple emails with Gerald Handler who, along with Elzbieta Zoclonska, is gathering data for this object and he says the best region to concentrate on are the Si III lines at 4553, 4568, and 4575 Angstroms. Emails are: Gerald Handler: gerald@camk.edu.pl Elzbieta Zoclonska:...

I've been knocking around with this problem ever since acquiring the LHiRes. I focused the slit using a 300mm telephoto lens and DSLR, shooting through the grating position (the grating had been removed). The telephoto/camera had previously been focused to infinity, and then the auto-focus turned of...

Hi Umberto:

Ha! In fact, I had noticed that possible emission feature but was uncertain due to the somewhat ratty S/N, so the following night I went back to the star and tried another - ironically enough exposing almost the exact same time as yours. Indeed the feature is real.

Mike

This is not an ideal setup for a star so faint - but I had the time and did not want to change the configuration - LHiRes 1800 - 23u - 5400 seconds. Unless I got the wrong star, it appears there is no emission.

Mike Potter
Beverly Hills Observatory

Until the definitive solution is developed by Shelyk I've built my own remote operation solution for the upgraded LHiRes calibration module. The main component is a model B Raspberry Pi, which is kind of like using a sledgehammer to kill gnats - as it's a full-blown computer on a card the size of a ...

Just some quick thoughts regarding the wavelength drift in the LHiRes III wrt temperature changes; The micrometer that is used to adjust the grating turret has a spindle that appears to be some sort of stainless steel. Looking up the coefficient of thermal expansion for stainless steel I found vario...