Sunlight situations that DO Work.

Prism Suncatchers want direct sunlight. The best place to receive direct sunlight AND land the rainbows is in front of a southerly window. East, west, and south are going to receive sunbeams throughout the day.  East works as well as west as long as their isn't something blocking the sun from coming in the window. When I say "land" the rainbows, I mean a surface NOT exposed to the direct sunlight - so there is a contrast between the bright light coming from the prism onto a shaded surface in your home.

The first time I saw the SunRain rainbow maker "work" was in our living room.  I hung the prismcatcher at an open spot of a south window. The prisms refracted the sunbeam into small rainbows in the window frame and adjacent wall.  Further away from the suncatcher the rainbow spectrums got bigger and were stretched longer BUT they were just as brilliant as the rainbows near the suncatcher.  No light was lost in the greater distance.

On the other side of our living room (the width of the house) forty feet away were the longest, widest light spectrums: about 14 inches x 5 inches.  Some rainbows were hitting the side walls at an angle and were stretched (there was some light lost in these elongated rainbows). Our walls are light yellow or white, which looks grey in the enclosed room.  The light from the prism is similar to a laser beam where the intensity is the same where the beam lands.

Sunlight Situations that DON'T Work

Cloudy days: NO.  Hazy days: NOT REALLY. Still light but the sun has set: NO. Night: NO.  LED flashlight: NO.  Incandescent flashlight: NO.  Halogen flashlight: NO.  Xenon flashlight: YES, if the light is strong but even this is not as good at direct sunlight.  The Xenon flashlight I have has six D-cell batteries and I can see washed out rainbows in a darkened space with a narrow beam of light pointed directly at the prism suncatcher.  I'm working on an experiment with a Cadillac Escalade Xenon headlight powered by a car battery, igniter and a step-up transformer ballast. I'll let you know if that works.

Why only Sunlight

Making rainbows with prisms requires a strong light source in a focused beam. Also, and this is BIG, the light needs to be full spectrum for the prism to have bandwidth to divide into respective wavelengths. LED doesn't work for that reason; it has a limited spectrum.  Same with red laser or Ultraviolet (black) light - there's nothing to divide.  So a strong, focused, full spectrum beam is essential.  The SUN is the BEST. 

Prism Optics

Clarity of the glass is important.  There are suncatchers with plastic prisms (don't buy them) and they are not brilliant.  The Asfour lead crystal chandelier pendants used in the SunRain prism suncatchers is high quality and high clarity.  The facets are smooth and the facets are long.  A crystal ball with tiny triangles will only give you a Disco Ball effect, no long rainbows.  Rainbows from a three inch prism are fantastic, and there's bigger prisms than than that.  The angle of incidence plays a part as well.  More prisms and more facets makes more opportunities to catch the beam and more surfaces to refract spectrums onto your walls, floors, and ceiling.  "There's rainbows everywhere" is what my grand daughter says :)