Re: Dimming hot lights

[andrew fildes <afildes@netlink.com.au>]

You don't want to be moving hot lights around too much, esp. big ones 
- gets expensive in blown globes - the studio at school goes through 
a lot of globes/bulbs because the kids aren't too careful. Paterson 
used to make a high/low switch but it wouldn't handle 650W. I thought 
household dimmer switches were little rheostats (circular coils) 
rather than resistors. I once had some old cinema lighting sliding 
dimmers - huge exposed things that would handle huge amounts of 
current - but were a tad dangerous for amateurs as they were totally 
exposed. Try talking to a local company that does theatre lighting - 
they may have a small unit that can handle this or know where you can 
source one new or used. Be safe!
AndrewF





> I understand that the suggested way of adjusting the light level of 
> hot lights would be to move the light, use a reflector or diffusion 
> material etc. but I was wondering about just using a household 
> dimmer. I bought some old 650 watt movie lights and I looked in the 
> local hardware store where it seems all the dimmer switches were 
> rated at 600 watts.
>
> > > From my probably incorrect understanding of electricity, a 650 
> > > watt lamp at 110v will draw 5.9 amps. A 600 watt dimmer will 
> > > safely allow 5.5 amps of current. Is that .4 amps the light wants 
> > > to force through the dimmer going to add a lot of excitement to my 
> > > shoot, just make the dimmer very warm or not have any noticeable 
> > > effect?
>
> Greg