First Lunar Spectroheliograph image?

[Merlin66 (Ken)]

J Paladin has just successfully applied his small SHG to the imaging of the Moon in narrowband sodium wavelength.
The image required 1sec exposures per frame.
I think this may be the first amateur lunar image recorded using the SHG!
A fantastic effort which shows the potential (with larger telescopes) of the SHG scanning techniques on brighter astronomical objects.
Congratulations, Well done!
Onwards and Upwards
(EDIT) the guys on the Astronomical Spectroscopy forum have corrected me! There have been various successful spectrographic scans of planets and nebula over the past few years....
http://astrosurf.com/joseribeiro
http://www.astrosurf.com/buil/scan/demo.htm

[algwat (Alan)]

Gidday Ken,
That's interesting. So, is it like a drift technique across the slit. No hard locked tracking to keep object on the slit??

[Merlin66 (Ken)]

Alan,
Yes, you can use a stationary set-up and just allow the sun to drift across the slit gap - it takes about 120 sec to obtain a full scan.
Each frame of the solar spectrum AVI recorded is then "sliced" into very narrow sections (one or two pixel wide) centred on the target wavelength and recombined to produce a spectroheliogram, a mosaic image at the selected wavelength and bandwidth.
Bandwidths down to <2A (much better than the commercial narrowband commercial filters) can be regularity achieved.

[Rob_K]

Fascinating stuff Ken - look forward to your own progress on this.

Cheers -

[Merlin66 (Ken)]

Thanks Rob!
The components of the 100mm SHG are now all together - just need some time to build, assemble and test.
Got side tracked with the observatory build and a " Southern Survey of emission stars using the objective prism(s)" - a project which has been bubbling for a few years now.