Control/Dimming Dimming solution for Source Four Follow Spot

joeboo46

Member
OK so I am out of ideas anyone have any good solutions for dimming a SOURCE FOUR foolowspot, other than cueing it into the show?

My current situation is: A 14degree SOURCE FOUR leko with a full city theatrical followspot outfit (yoke, drop in boomerang, and counterweighted handle) Only problem with the setup is the manual dimming which currently consists of a household 1000w dimmer (with constant power) zip tied to the yoke, it's hard to do slow fade ins/outs and they keep failing in the middle of the show.

Does anyone know of a dimmer that might be made for this application (someone mentioned to me this may exist) or have a better solution?
 
You can't tie it into a dimmer and write it in the cues for the show? That would be best...

Otherwise I would suggest trying to find a Rotary household dimmer instead of one of the slider ones. I have found that they usually dim smoother than the slider style. Other than that I can't really suggest anything else other then grabbing one of those small single channel dimmer packs with the slider built into the pack. Like one of these

Elation Unipak Single Channel DMX Dimmer Pack
 
In the olden days of yore, I ran an incandescent followspot with constant power to the fan and the lamp run through one of these:
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Staco Variable Transformer 1000* Series ,

with a dial on it large enough to be moved by my foot.
A 10A model is available from many sources new for around $100, or used on ebay for $0.99 +$17 shipping. Just be careful of supplying 140V to your 115V HPL lamp!

(Those who were driving cars in the 1950s may remember something known as a "Necker's Knob":rolleyes:. Same concept, except using one's foot.)
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(Photo: Death in El Segundo | The Daily Mirror | Los Angeles Times )

According to this: Dimmer, Autotransformer - ControlBooth, it worked for STEVETERRY also! (I don't know about the foot part, though.):)
 
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(Those who were driving cars in the 1950s may remember something known as a "Necker's Knob":rolleyes:. Same concept, except using one's foot.)

Those are still used on a lot of boats on the steering wheels. The ferry I used to work on had one and so did one of my friends 21' SeaCat. We called them "Suicide Knobs" because of the reason they were outlawed for use on cars since a lot of people were killed when they spun the wheel too fast and flipped their cars or boats.

Suicide knob - Wikipedia, the free encyclopedia

$100 for an Auto-transformer...wow, I would just go with that Elation pack I linked to. It's about the same price at $109 and you wouldn't have to deal with the weight and heat generated. Plus it has a remote slider so you can leave the pack on the floor and then strap the small slider to the fixture.
 
yes I use a Leviton 1000W slide dimmer for my S4 follow spot. However I made an L Bracket that I rivetted to the side of the box containing the dimmer. I then drilled four holes in the other arm of the bracket. The hole spacing allows two U bolts to fit through. The U bolts fit around the stand and through the bracket. When tightened the dimmer is rigidly attached to the follow spot stand which allows the operator to adjust the dimmer smoothly with one hand while using the other hand to track the spot. Easy and cheap. The U bolts can be bought in RONA, Lowes, Home Depot for about $2 each and the bracket was made from a piece of aluminium bought in the same store from the steel and aluminium section box.
 
Why can't you just cue it into the show? That was the main advantage of a Source4 spot.

Mike
 
I can't cue it into the show because this is what the designer wants besides it is a tour and I have different operators every day. It's better to not have the light on at all than have the light come up and be in a completely random place. I do not believe cueing the light into to the show is the only reason for source four spots the are very cost effective, lighter weight than a lycian short throw and take up alot less space when packing them in a 53' trailer (that is already packed to its capacity). I do thank you however for the Elation single channel dimmer solution I am going to look into that and see if the company might be interested. Believe me I would love to cue these things into the show, but I am only the assitstant elec. that gets to fix the followspots everyday when they come off the truck, oh yeah i'm the guy that hears it when the cues aren't done properly (fade ins/outs, dimmer frys during act 2, dimmer falls off yoke, etc.) Ahh the joys of being the assistant.
 
I remember my time as an assistant. Not very fondly I am afraid. On tour we always used truss spots, but I can see the size/weight savings. If you CANT cue it into the show (which it sounds like you cant) then the Elation sounds like your best bet. The only reason I used Source 4 Spots back in the day was so I could control the fades. *shrugs* But I had access to a Lycien.

Mike
 
Yup they are truss spots also forgot to throw that into the mix . . . and originally on the first national i do believe they were Lycians as a matter of fact the plot we got in the shop had lycians on it but the paperwork had 14 degrees. Sigh . . . Irony is, power comes from a dimmer pack mounted in the truss directly in front of the chair dimmer is parked on. Again Sigh . . .
 
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Yup they are truss spots also forgot to throw that into the mix ...
Well then forget about about my option of something foot-controlled.:( However, I still think an ATD is the best solution. It's easier to do gentle fades on a large dial with tactile feedback. A triac-based single dimmer will most likely have a horrid dimmer curve, and create RFI and filament noise. Also, the Elation product appears to have been discontinued.

Of course, if cost is not a factor, this controlling this.:twisted:

I also seem to recall a Kliegl ERS/followspot with a fully-closing iris mounted in the colorframe slot used as a douser.

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...Irony is, power comes from a dimmer pack mounted in the truss directly in front of the chair dimmer is parked on. ...
Wait, this might not have been so far off after all. Does the dimmer rack allow for DMX A and DMX B inputs?
 
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I have found that the Leviton 1kW slide dimmers have a good dimming characteristic although when I bought mine they were $40 each and then you still had to put them in a box - they are 10 years old now so they were actually expensive when I bought them. They also include an adjustment to allow you to set the turn on threshold to eliminate ghosting.

Just to clarify a post I read above; TRIAC dimmers only use one TRIAC per channel, it is SCR or thyristor dimmers that require two devices - one for each half cycle - for each channel. A TRIAC is actually two SCRs back to back in a single device.
 

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