New guide on slit feature by Astroart

[Paolo Berardi]

Thanks to promptness and kindness of Astroart developer Fabio Cavicchio, we have a new specific tool for guiding with a reflective slit. It follows a recent topic on Astroart forum wherein I and Ken Harrison talked about our need.

The tool is mainly based on a new algorithm for precise position detection of a star image cut by the slit and some options to fine-tune the guide reference point in realtime (change position and other parameters without stopping autoguide function).

I performed several tests with Lodestar camera, C9.25 and Lhires III, finding an excellent behavior with various magnitude star (also in severe sky conditions such as strong turbulence, cloud passage, etc.). In many cases, guiding is also possible on a field star when the target is on slit.

At this link you find a brief tutorial I prepared with step-by-step basic operations (I hope it is clear):

http://quasar.teoth.it/html/spectra/AA_slit_guide.pdf

It seems to me that the implemented features are sufficient to cover most of situations concerning guide on reflective slit. Let me know what do you think about. CCD Control Interface 5.30 with SDK, just released, contain the spectro module as a kind of pre-release, in the next version will be official.

Clear skies!
Paolo

[Paolo Berardi]

Hi all, just to point out that the new Astroart 6 service pack 1 (released on december 15th) add the ability to move the reference guiding point with half a pixel steps (before was 1 pixel).

Choose Camera control 6.2 beta.



That could be useful in cases of undersampling condition for guide camera image (you can achieve a better target alignment on the slit axis).

To set half pixel coordinates, press CTRL + left mouse click on the border buttons (nothing else has changed compared to the previous version).

Paolo

[Ken Harrison]

Paolo,
Fabio certainly seems to be very supportive of the spectroscopy community.
I recommend AstroArt as an excellent camera control/ acquisition/ pre-processing solution.

[Arnold de Bruin]

Great tip!
This immediately made me upgrade from AA5
Arnold