Light box. Red?

[ChrisV]

Thinking of making a light box. Can you use red LEDs?

The reason is that I want to use it out in the field as I often swap cameras during the night for video astronomy. And don't want to disturb others.

[OzEclipse]

Chris

Yes you can and they're very power efficient, just be sure to have a big enough fixed resisitor in series with a potentiometer to vary brightness so you don't exceed their maximum operating current. If you are not sure how to work this out, post the details of the LEDS, ie the exact part number and the voltage of your power supply and we can help you select the correct potentiometer and current limiting resistor.

Joe

[ChrisV]

Is the colour I'm not sure about. Any reason you can't use red v white. I use OSC cameras.

[LewisM]

For a light box (for making photographic flats), you want white LED's.


If you make a light box properly, you have next to zero light leak when in use anyway, and you simply turn it on when on the telescope, and off before taking off.

[OzEclipse]

Oops! I misunderstood. Ignore my advice. I thought you wanted to make a light box for visual use reading charts, making notes or sketching. Red leds unsuitable for a flats light box. White leds required with plenty of diffusion for even illumination. Current limit resistor still required. Joe

[ChrisV]

A month later. Okay so I need white light ...

But if I use a mono camera and a filter wheel. Do you do flats with or without the different filters ? If you don't use the filters then what about dust bunnies

[billdan]

In theory you are supposed to do a different set of flats for each filter, however if you can keep the filters clean and dust free, you can get away with only using a Luminence set of flats for all filters.

Bill