This one is literally a light box. I sat down to make a box today, and then thought of all the cardboard boxes I have stored away..... so one of the observatory building purchases finds a new use....
I went looking for LED's and resistors etc to make a white LED array - but found these LED modules at Jaycar - $19.95 for 10x3 LED's, prewired ready for 12V DC - draws about 150mA. (
Jaycar cat no ZD0492)
These are double-sided-taped to a white board in the bottom of the box, and the top of the box is cut out for a piece of 3mm opal acrylic. Produces a very nice even light, and very light on the arms to hold up to the objective too. I wired an RCA plug to match my DIY dew heater arrangement.
This was made as a prototype, but I may just cover it in contact to fight dew and see how long it lasts!