Made myself an artificial star today (yeah it's cloudy).
It was done with a xmas light running on a bank of 4 'AAA' batteries. Whilst not the best artificial star method, I found by concentrating (see pic 1) on one little point of light within the globe itself was more than sufficient to suit my needs.
The last time I collimated this scope was close to 12 months ago & it was only a fraction out - 1 little tweek of 1 screw was all that was needed to get it on the money.
9800mm is a conservative estimate; 3X barlow + 4" extension tube. Collimation was by eye, & then confirmed with an Imaging source camera (DBK).
Pic 2 is of the globe, & the small guage car speaker wire used to wire it up with.
Unfortunately I couldn't get the 'star' as far away as I would have liked to. This is about 75ft away where as it should have been what - about 300ft...?
I don't think the distance to the artificial star matters for collimation John, so long as it's far enough away to form an image. A greater distance is needed for assessing optical quality, to avoid introducing SA from memory.
Has the collimation held when the scope is pointed up at a star?
