As i wrote some days ago, I planned on doing some hack so control KStars with a Wiimote.

It turned out KStars isn’t the right target, as it seems to have no plug-in support (and I don’t want to modify core yet, as i’m still in an experimental phase).
But reading data from wiimote and correctly interpreting was already done some days ago, thought it was a little bit hard, so I switched to Stellarium instead.

This is the result:

Of course it’s just experimental code, it’s barely usable.. but it’s a start.
Source is here: https://github.com/rockman81/StellariumWiimotePlugin

Now some technical stuff:
The Wiimote gyro sensors aren’t easy to read, as they don’t send you current angle, but only
It doesn’t report current angle, instead it does report angular speed.
But afterall you can deduce current angle just dividing speed by elapsed time between each message report.
I had to do some tries before finding the proper way of “moving view window” on Stellarium.
It’s not so well documented, and i’m not exactly happy about current solution, but it works, and i’ll ask some help in their mailing list soon.
This solution anyway is easier than i thought, as it only receives as input angles delta, meaning it’s also easy to “align” your telescope to stellarium (just point an object with telescope, then manually point stellarium to that object).
What’s missing:

  • better calibration (angles “seem” correct, but i’m not entirely sure…)
  • better movement translation (i’m ignoring one axis, they should be all taken into account, and compensate misalignment).
  • Maybe some alternative way of displaying wiimote data in stellarium, such as a “virtual” object in sky. this way you can see how close is your telescope to a desired object.
  • Equatorial mount support (currently if there is an axis rotation it’s not detected and properly corrected, and it’s interpreted the wrong way).
  • ….many other stuff, but it’s too early to get a detailed list 😛

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Finalmente sono riuscito a finire l’elaborazione di un insieme di riprese lunari che avevo girato ad agosto 2011.
Ci ho messo parecchio sia per mancanza di tempo, sia perchè per elaborare avevo bisogno di registax.. che però esiste solo per windows (e io windows, per definizione, non lo avvio praticamente mai...).
Alla fine sono riuscito a capire come farlo funzionare con wine su Linux, senza fargli occupare tonnellate di RAM (il grosso problema è che con registax con wine non gestisce gli AVI compressi... ma esportando l’avi in immagini PNG è miracolosamente andato), e quindi a riprendere l’elaborazione.

Dati di ripresa: ho usato un Celestron Astromaster 130EQ, focale 650mm, fuoco diretto.

Webcam Microsoft Lifecam HD 3000, risoluzione 1280×720 (un po’ troppo rumorosa sugli oggetti deboli, ma tutto sommato accettabile per uso astronomico).
Ho elaborato i filmati con Registax 6, quindi messo insieme il mosaico con Hugin, splendido software Open Source (si, anche per Linux, niente wine quindi).

Il mosaico risultante è stato poi rielaborato con Gimp.

Moon - Mosaic

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