When one attends theatre productions, you can sometimes see a completely white background that is blue and then changes grey to dark for nighttime. I would like to know what that kind of background is called and how that kind of lighting is achieved.

Is it that the light is cast onto it from the top or from the back?

The background is known as  cyclorama or cyc for short. The lights usually shine down on the cyc from above and in front of it, but can also be lit from below if there is something to hide the instruments. With a couple sets of different colored lights you make a wide range of colors by varying the intensities.

Dan

Thanks very much for the information.

I would also like to ask if it is necessary to use a particular kind of cloth to function as the cyclorama. Can I use normal canvas? Could I just use plain white canvas?

For the cyc lights, could I use just flood lights or should I use specifically cyc lights?

This is for a school production so I really don't know much about this. Your help is very much appreciated.

Following on from DANLB - The Cyclorama, was originally known as the ?Sky cloth?.

The Cyc lighting is normally from a batten of lamps - floods [scoops] joined together to cover the width of the cloth, with the cyc lighting from above in the ?X? position. However you can enhance with side light &/or with a groundrow. Also it is sometimes more effective to use a ?Reflector cloth upstage of the cyc & bounce the light through it. While there is a lot of materials used for the cloth, houndstooth or sharktooth weave is better.

If you only use an ?x? position Cyc lights wash, you should ensure that you position the batten, to give maximum coverage, with each colour wash & can avoid light scallops from the lamps, this can be rectified by the globe choice, reflectors &/or the angle of light.

Also it is helpful to have ?barndoors fitted to cut out over spill & light halation.

The ?Skycloth? was traditionally sky blue, with the advent of colour gels & electric lighting, it became a white cloth. It was adopted from Theatre by black?nwhiteTV studios, who renamed it cyclorama & changed it to an orange colour. This gave a better colour definition for their transmission.

Again with color TV, it reverted back to white.

One thing is if your cyc is left hanging for any period of time, it is good policy & practice to avoid touching the surface, as this can & will wipe away the covering surface dust & it will be seen as a mark under lights. If you can fly the cloth, bouncing it can remove a certain amount of airborne dust evenly.

Also the trick is to stretch the cloth tight, to get rid of the wrinkles, by the use of a tail batten & side cloth stretchers. Screw joint steal conduit or small diameter water pipe, is good as the tail batten. It is easier to join lengths together as it is slides into to the tail pocket.

Halls stage equipment has a new fast stretcher device, that does away with the tired old pieces of wood & rope.

Technically you could use any type of fabric (be sure it's flame retardant), or even a wall painted white and pretty much any kind of instruments. What you will loose is the "quality" of the effect. The more equipment you use that is made for this purpose the better the effect will look. I did a production of Our Town recently where we just painted the wall behind the stage white and lit it with some strip lights from below. Definitly not as good as having a real cyc, but it worked ok.

Dan

I would also like to ask how one makes transitions from different colours to indicate the change of time during a day. The scene is set in a garden outside and the times of day would be afternoon and sunset and evening. Which colours of lighting would be used and how would they be combined? Thanks for the information!

Typical cyc light colors are blue, red, green, and the occasional amber.  In your situation you could light it with blue and a little green for the daytime.  For sunset experiment with combinations of blue and red.  For the nighttime a very low level blue can be used.

we use red blue and gold most outdoor scenes are done with the blue and a hint of gold if there is anger in the character or right before the character enters the lights turn red it adds a cool bit to the play.