How To: Make an Artificial Star

iceman (Mike) · #1 13-01-2006, 07:03 AM

Hi all.

Barry (Muddy Diver) has kindly written a great article on a DIY project he did - Making Your Own Artificial Star.

You can read the article at the IceInSpace How-To page, or directly by clicking on the link below:

Making Your Own Artificial Star

Thanks to Barry for his contribution.

If you'd like to submit an article/how-to/review for the site, please contact me.

iceman (Mike) · #2 16-01-2006, 07:36 AM

Placeholder replaced with article. Bumping thread.

h0ughy (David) · #3 16-01-2006, 07:43 AM

nice article

Muddy Diver · #4 20-01-2006, 12:03 PM

Thanks Houghy.

I found it more useful for the lower end scopes or those which are badly out of collimation. I doubt that you eperts and perfectionists would get much value from it but it works for me.

I needed to clean my mirror last week and was able to check the collimation straight afterwards not wasting any of the rather limited viewing time we currently get.

Barry

johnno · #5 20-01-2006, 02:31 PM

Hi Barry,
Thanks for a great article,Very well done.
Regards.
John

cristian abarca · #6 01-02-2006, 05:43 PM

I have a few questions regarding the artificial star. In the article a box is used. does it have to be a box (cube) or can it be smaller? Is the function of the box only to hold the electronic components? I have all the materials to make one and I just want to confirm some of the details.

Regards Cristian

Muddy Diver · #7 05-02-2006, 05:19 PM

Christian

Sorry for the late response. Work took me into the goldfields Of WA this week where the skies were soooooh dark I couldn't believe it. AND NO SCOPE!

I adapted the square box from a tall rectangular one which I saw. The box is handy to house the electronics but these could be afixed to the other side of a plate I suppose. The main reason I went for a box design was so that I could just set it down on any suitable surface and not have to worry about fixing it there. (I set mine up on a stepladder).

The square shape ensures darkness around the star in all directions when viewed through your scope. I changed this from the model I saw as it appeared very thin in one direction.

Hope this helps and good luck!

Barry

Quote:

Originally Posted by cristian abarca

I have a few questions regarding the artificial star. In the article a box is used. does it have to be a box (cube) or can it be smaller? Is the function of the box only to hold the electronic components? I have all the materials to make one and I just want to confirm some of the details.

Regards Cristian

frogman (Anthony Lord) · #8 05-02-2006, 06:11 PM

would you get the set up closer by placing the box further away or is there a set distance ?

cristian abarca · #9 05-02-2006, 10:35 PM

Thanks Barry, that has answered my questions. Now to make it. Shame about not having your telescope with you.

Regards Cristian

Muddy Diver · #10 07-02-2006, 02:02 PM

Hi Frogman

Hmmmm Frogman ... Muddy Diver... Scuba much?

I think the smaller you can get the led the better so the further away you can go the better. But as this device is an aid to gaining some rough calibration during daylight hours, yopu may need to consider placing a hood of sorts over the "star" if say you placed it at the other end of an open carpark for example. Otherwise I would worry about not seeing enough light from the LED. Of course if you're lucky enough to have a huge shed or odd aircraft hanger on your plot which can shut out some light this might be easy!

I guess the real benefit of this star is the saving in time collimating at night when you want to be viewing. So rough collimation in the garage with the doors down was sufficient to save me around 30 minutes or so last time I used it.

Muddy Diver

Quote:

Originally Posted by frogman

would you get the set up closer by placing the box further away or is there a set distance ?

robgjames (Robert) · #11 18-05-2015, 10:18 AM

i needed to know how to make one - now i do. thanks.

julianh72 (Julian) · #12 18-05-2015, 03:45 PM

I use a 10 mm chrome ball bearing as my artificial star. If it is sunny, I put it in the sun at the far end of my garden (about twenty metres away) against a dark background. By my calculations (possibly faulty!), the image of the Sun on the 10 mm ball bearing is about 22 microns across, and at a distance of 20 metres, this is a "point" of light less than a quarter of an arc-second across - well below the diffraction limit of my scope!

If it is cloudy (or at night), I set it up at the far end of my longest hallway (about 10 metres long), turn off the hallway lights, and shine an LED torch down the hall to illuminate the ball bearing.

Both scenarios give me a brilliant, clearly distinguishable "star" image to bring in and out of focus.

algwat (Alan) · #13 21-05-2015, 09:48 AM

The Ball bearing is a great lateral thinking solution, like it, I'll try it.

Regards, Alan.

gts055 (Mark) · #14 21-05-2015, 10:44 AM

The optic fibre idea is neat. I have made my artificial star by placing a piece of aluminium cooking foil over the end of an led torch. You take a needle with a very fine tip and place the foil on a hard surface, then push the pin onto the foil to make the tiniest of holes. You can make several perforations to have a selection of sizes. Then wrap the foil over the front of the led torch. Mark