phrases?

[minimac]

hi there, would just like a little help with the following phrases? what do they mean? "electronic ballast version", "variable CTO" and this may sound silly but what does DMX actually stand for.

 

Thank you.

[david.elsbury]

What does DMX actually stand for?

Digital MultipleX

 

Referring to the ability to send many channels (512 per universe) of control data down a single pair of wires, much the same format as a serial link.

 

-david-

[Bryson]

"Electronic Ballast Version" A ballast is a bit of kit that allows a discharge lamp to work properly. (someone else will have to explain how) They come in two types: electronic and magnetic. Magnetic ones are cheaper but heavier. Electronic ones lighter but more expensive. Some moving lights come with a choice of ballasts.

 

"Variable CTO" Colour Temperature Orange. Colour Temperature is a way of measuring the actual colour of the "white" light you get out of something. Moving lights usually use discharge sources, with a higher Colour Temperature and so look more "Blue" than a normal theatre lantern. A CTO filter will alter the colour temperature of a light towards the lower end of the scale. You may wish to vary the ammount of CTO you put in in order to match your other lanterns. (Source 4s, for example, have a slightly higher colour temperature than most theatre lanterns.)

 

DMX: Digital MultipleX As in, a digital way of sending many different streams of information (in this case, 512 of them)

 

EDIT: Too slow on the DMX there... :D

[Ike]

When a discharge lamp is running it has very low resistance. It is the ballasts job to limit the current flowing through it.

[Jivemaster]

The arc in a discharge tube has a negative resistance at its operating point so a positive resistance/impedance is needed to stabilise it. electronic balasts can give better striking and running and lower weight but at a cost.