Lights back in the day

[JimP0771]

Hi All

I am sorry to bother everyone here as you are most all likely getting tired of me posting and asking questions I understand I will try to not post to much more. I had a question though. Many Many years ago when I was in elementary school I helped with an event there where the stage strip lights were needed to be turned on and off. These strip lights were operated by leavers that you pulled. If the levers were pushed alway to the front the light were off if you pulled the levers all the way back the strip light was totally on. Anything between front and back would make the strip light as dim or bright as you wanted. Today now those are now on breakers and are either all on or all off. Has anyone ever herd of this level things to work the lights? I thought it was strange. Is this how lighting was done before dimmer packs or dimmer racks and boards?

Thanks

 

[Van]

Jim, Yes, it sounds like you are describing Resistance Dimmers. The handle connected directly to a gigantic resistance module sort of like the rheostat on the wall for your lights. Something like this:
Also see the Wiki here: https://www.controlbooth.com/threads/piano-board.7918/#post-92972

Oh, and there are no Stupid Questions, and we love to hear them all. That's why so many of us are here.
Ok, Except maybe the wilting rose from Beauty and the Beast. If I never see another question about that I'll die happy.

 

[JimP0771]

Van. That is exactly what I am talking about. However the one the elementary school had was like the one that is in the picture on the link you had put on your post. They have sense gotten rid of these lever dimmers and are just using breakers for on or off. They don't really use there stage anymore of shows or assemblies. Just here and than. Thanks.

 

[JChenault]

Jim and van

Unless you are really old, these were more likely auto-transformer dimmers.

Similar in look to resistance dimmers, but they:
Did not need a ghost load
Did not use power when turned off
Did not generate lots of heat.

On the other hand they did need AC power

 

[SteveB]

And we never, ever get tired of questions.

 

[ship]

Dependant on the school, some were not designed for autotranformer dimmers, some later removed them and went circuit breaker control with no understanding of what/why they were doing it. That is history of the school. I often go into schools without control other than breakes of the half working strip lights. Mostly I see no indication they were ever dimmed. Of all strip lights... any you might come into contact with.. they should all be suspect for safety, lamp sockets and safety. Time for a service call on them well past service life of the light. And this is never in any install to do list in servicing. Strip lights are useful, but other than for a few thater's in the past, never gotten for over 20 years now, a request to service a strip light type fixture. With the demise of the Osram 100A/HAL/F #18970 it is a serious determent to Strip/Cyc lights in being more useful. Until something best in dimmable LED comes out for the various typs of strip/cyc light.. breakering and in general school maintenance staff lamping them or not is what it is. Seen some scrary fixes and lampings on installs.

Money to schools and theater programs is a thing especially to those without a large tax base... them schools that have to put on hold lighting upgrades in what ever the school has done to the lights working somewhat. Huge thing in just replacing the c.1950's drapery most often. Lighting upgrades... often can as next just afford a few LED color changing PAR's from FOH as per direct wash. Quality show lighting is if available... still there and not serviced or replaced. This the bulk of the the show's needs for lighting.

 

[JimP0771]

Dependant on the school, some were not designed for autotranformer dimmers, some later removed them and went circuit breaker control with no understanding of what/why they were doing it. That is history of the school. I often go into schools without control other than breakes of the half working strip lights. Mostly I see no indication they were ever dimmed. Of all strip lights... any you might come into contact with.. they should all be suspect for safety, lamp sockets and safety. Time for a service call on them well past service life of the light. And this is never in any install to do list in servicing. Strip lights are useful, but other than for a few thater's in the past, never gotten for over 20 years now, a request to service a strip light type fixture. With the demise of the Osram 100A/HAL/F #18970 it is a serious determent to Strip/Cyc lights in being more useful. Until something best in dimmable LED comes out for the various typs of strip/cyc light.. breakering and in general school maintenance staff lamping them or not is what it is. Seen some scrary fixes and lampings on installs.

Money to schools and theater programs is a thing especially to those without a large tax base... them schools that have to put on hold lighting upgrades in what ever the school has done to the lights working somewhat. Huge thing in just replacing the c.1950's drapery most often. Lighting upgrades... often can as next just afford a few LED color changing PAR's from FOH as per direct wash. Quality show lighting is if available... still there and not serviced or replaced. This the bulk of the the show's needs for lighting.

What I have noticed is most of the schools that I have done lighting in have had strip lighting. That is all the schools in my local school district. I am really not a fan of strip lights due to the fact that you can not really do much with them do the the fact it is just on and off with them. I mean you can change the light color glass or jells in front of the individual bulbs if you want to change the light colors but other than that there really is not much you can do with them. But when I they are the only thing the school has I make due with them. I have to say though that I find all these old lighting controls fascinating. I wonder if these were what they use to use on Broadway.

 

[SteveB]

Until 1975, Broadway typically used a variation on the DC resistance dimmers as seen in Van’s photo.

As the theaters were empty of equipment until a particular show loaded in and had its run, the dimmers were all big 12 or 14 dimmer “portable” “Piano boards”.

There’s a thread from CB here

https://www.controlbooth.com/wiki/Dimmer-Resistance

In 1975, A Chorus Line changed everything by using a computer lighting control and A.C. SCR type dimmers for the first time. The rest is history.

 

[TimMc]

Uncle Daddy, tell us about ConEd supplying direct current service to Broadway theaters, too!

 

[SteveB]

Uncle Daddy, tell us about ConEd supplying direct current service to Broadway theaters, too!

I always found it remarkable that DC still existed in the theaters in ‘75. I can imaging that ConEd was happy to not have to keep providing that type of service.

I also recall that when I started at Brooklyn College in ‘81, we had a 14 plate piano board in the basement, I assume as a teaching tool, though it wasn’t hooked up. I’ve no idea who got rid of it or when.

 

[JD]

My understanding was that DC was supplied by motor-generators, usually close or within the theater. Resistance dimmers worked on DC or AC as resistance is resistance and does not care. As to WHY they were still DC long after more efficient autotransformers systems were introduced, and still even after solid state dimmers came along, can only be attributed to one thing: "That's the way it's always been done!"

 

[tjrobb]

I mean, we have a motor-generator feeding DC to our elevator. But since the controls are from 1928 I suppose it makes sense. (Though it has mandatory safety updates. We're not animals).

 

[RonHebbard]

I always found it remarkable that DC still existed in the theaters in ‘75. I can imaging that ConEd was happy to not have to keep providing that type of service.

I also recall that when I started at Brooklyn College in ‘81, we had a 14 plate piano board in the basement, I assume as a teaching tool, though it wasn’t hooked up. I’ve no idea who got rid of it or when.

@TimMc and @SteveB One of our largest hydro electric dams still maintains two 25 Hz. Generators in operation, one running and one on standby. One of the steel mills in Hamilton, Ontario still has 25 Hz. motors in operation as does a major machining company in St. Catherines, Ontario, approximately half way between the Sir Adam Beck dam in Niagara Falls, Canada and Hamilton. The company in St. Catherines MAY be a plant manufacturing GM engines although I may be incorrect when it comes to which plant it is in St. Catherines.
Toodleoo!
Ron Hebbard