dimmers
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DPStewart
Veteran
There are a number of DIY high-wattage dimmer kits or instructions out on the web (1000+ watt).
There are 2 schools of thought on it:
1. Dimmers don't really fly because when you dim a tungsten/halogen bulb down - its color temperature decreases thus becoming yellower and yellower.
2. The color temp dimming effect is fine - you just have to re-balance your exposure with each change. While this is fine in concept, you do have to beware of mixing color temps if the light you are dimming is not the only tungsten/halogen light on your scene.
The high-wattage dimmers for sale out there are pretty expensive - which seems to be the reason for all the DIY kits.
There are 2 schools of thought on it:
1. Dimmers don't really fly because when you dim a tungsten/halogen bulb down - its color temperature decreases thus becoming yellower and yellower.
2. The color temp dimming effect is fine - you just have to re-balance your exposure with each change. While this is fine in concept, you do have to beware of mixing color temps if the light you are dimming is not the only tungsten/halogen light on your scene.
The high-wattage dimmers for sale out there are pretty expensive - which seems to be the reason for all the DIY kits.
Run&Gun
Veteran
I build my own high wattage dimmers. Use Lutron 1K watt linear fader dimmers that have an on/off switch. I like that set-up much better than rotary dimmers that combine the dimmer and on/off into the single rotary dial. The 1K's are about $20 at Lowe's or Home Depot. I mount them in a single metal outdoor box and use 15' extension cords to make the ends.
Something else to be aware of besides color temp dropping as you dim down, some lamps will start to "sing"(buzz). And a lot of it is dependant on the type and brand of lamp(avoid cheap ones). I don't notice much on most of my Arri's, but my pattern projector(Source Four) is another story.
Something else to be aware of besides color temp dropping as you dim down, some lamps will start to "sing"(buzz). And a lot of it is dependant on the type and brand of lamp(avoid cheap ones). I don't notice much on most of my Arri's, but my pattern projector(Source Four) is another story.
Michael Carter
Veteran
Those harbor freights are great, and there are often generics on eBay. Sign up for HF's emails if they're local - they send great coupons all the time, 20% off one item, etc. I call them "dimmer coupons".
How many times have you seen a tungsten lamp - pro or at home - fail while running? How many times do they fail when you turn the switch on? How many times are they suddenly dead when you throw the switch (because they failed at power off)? Switching on a bulb is the hardest thing you can do to it (followed by switching it off, in my experience) - I have a wall at home with can lights on dimmers - of 8 lights, we've replaced ONE bulb in 8 years - because the dimmer brings them up to heat softly.
As for the color temp - read Roger Deakins' forum - he uses dimmers to control color temp and get that "warm" look he's known for. (Oscar nominated for).
How many times have you seen a tungsten lamp - pro or at home - fail while running? How many times do they fail when you turn the switch on? How many times are they suddenly dead when you throw the switch (because they failed at power off)? Switching on a bulb is the hardest thing you can do to it (followed by switching it off, in my experience) - I have a wall at home with can lights on dimmers - of 8 lights, we've replaced ONE bulb in 8 years - because the dimmer brings them up to heat softly.
As for the color temp - read Roger Deakins' forum - he uses dimmers to control color temp and get that "warm" look he's known for. (Oscar nominated for).
Run&Gun
Veteran
I've heard people talk about the HF rotary speed control/"dimmers" for years and there's a Harbor Freight near me(maybe 10 mins away) and the few times I've gone in there, I've never been able to find them.
Terry_Lasater
All about the Caption
alaskacameradude
Veteran
I live in a place where I have to buy everything via the internet, but I get Harbor Freight flyers and
the 'rotary speed control'/dimmers are in the flyers. I have about 6 of them so I can put one on
every light. It sure beats trying to scrim a bunch of lights. You can dial in your lighting to exactly
the intensity you want. Yes, the color temperature does change a bit when using them. But all you
do, is just wait until you have your lighting dialed in and white balance under whatever light you are
using. I personally think they are one of the best tools you can have if you have a limited budget
and do a lot of corporates or other films that require the standard interview. It really allows you
to do a lot with lights that are lower budget and don't have buit in dimmers on them. Just plug one
of the dimmers in for every light and you have a ton more control over your lighting setups.
the 'rotary speed control'/dimmers are in the flyers. I have about 6 of them so I can put one on
every light. It sure beats trying to scrim a bunch of lights. You can dial in your lighting to exactly
the intensity you want. Yes, the color temperature does change a bit when using them. But all you
do, is just wait until you have your lighting dialed in and white balance under whatever light you are
using. I personally think they are one of the best tools you can have if you have a limited budget
and do a lot of corporates or other films that require the standard interview. It really allows you
to do a lot with lights that are lower budget and don't have buit in dimmers on them. Just plug one
of the dimmers in for every light and you have a ton more control over your lighting setups.
paulears
Veteran
As a theatre person, we live with dimmers as an essential part of the job - so maybe I can chime in on a few areas.
As for the colour shift, over here, it was common for TV studios to run all their lighting at about 70% on the fader. The colour shift going to full, or down to half was very manageable. It does mean your colour balance will probably be around the 2700K mark as an average.
The noise often heard is called filament sing. The chopped waveform from the dimmers physically makes the filaments vibrate, and this is what you hear. The different styles of filaments respond differently, hence why the ETC, which has a very different layout of the filaments, makes more noise.
Anything less than full power makes considerable extension to the lifespan of your lamps (globes is US!)
One thing to watch with dimmers designed for industrial use, rather than our world is that they have no need for any filtering, and the function of a semiconductor dimmer is simply to change the point in the gentle curve of the AC waveform where it suddenly dives to zero volts, or switches back up to the curve. This produces a very hard edge to the waveform, which creates harmonics at multiples of the supply frequency. In video studio/theatre dimmers there is a great deal of care put into reducing these, which prevents buzzes and whines entering the audio systems. So if you are drawing lots of current with bigger Arri style Fresnels, and you start chopping it up, expect nasty noises in any audio kit with less than perfect shielding. This noise can be identified by changing the brightness of the lights and if the interference changes tone, it's the dimmers!
Personally, I'd rather use a dimmer than mess around with scrims, and you don't burn yourself on a dimmer!
As for the colour shift, over here, it was common for TV studios to run all their lighting at about 70% on the fader. The colour shift going to full, or down to half was very manageable. It does mean your colour balance will probably be around the 2700K mark as an average.
The noise often heard is called filament sing. The chopped waveform from the dimmers physically makes the filaments vibrate, and this is what you hear. The different styles of filaments respond differently, hence why the ETC, which has a very different layout of the filaments, makes more noise.
Anything less than full power makes considerable extension to the lifespan of your lamps (globes is US!)
One thing to watch with dimmers designed for industrial use, rather than our world is that they have no need for any filtering, and the function of a semiconductor dimmer is simply to change the point in the gentle curve of the AC waveform where it suddenly dives to zero volts, or switches back up to the curve. This produces a very hard edge to the waveform, which creates harmonics at multiples of the supply frequency. In video studio/theatre dimmers there is a great deal of care put into reducing these, which prevents buzzes and whines entering the audio systems. So if you are drawing lots of current with bigger Arri style Fresnels, and you start chopping it up, expect nasty noises in any audio kit with less than perfect shielding. This noise can be identified by changing the brightness of the lights and if the interference changes tone, it's the dimmers!
Personally, I'd rather use a dimmer than mess around with scrims, and you don't burn yourself on a dimmer!
Michael Carter
Veteran
They're usually with the router bits. Sometimes I have to ask, our HF people here are pretty friendly and know where the stuff is.
Michael Carter
Veteran
The only problem I've had is one getting very very VERY hot and then dying. This with a 500 fresnel.
In all fairness, I think I'd used that as a speed control when I wet-ground my concrete countertops... it had been soaked through and through with wet concrete dust...
In all fairness, I think I'd used that as a speed control when I wet-ground my concrete countertops... it had been soaked through and through with wet concrete dust...
homestar_kevin
Well-known member
I have had the harbor freight dimmers for years now and they're perfect.
I have at least 6 right now and none buzz.
They're the great.
Also if you need stingers they're good too.
No black ones, but they have 50ft 12gauge stingers for under $40 bucks
I have at least 6 right now and none buzz.
They're the great.
Also if you need stingers they're good too.
No black ones, but they have 50ft 12gauge stingers for under $40 bucks
Run&Gun
Veteran
Thanks Terry and Michael. I actually checked out their site after posting. I went by my local HF Sunday after eating lunch and found them(BOTTOM shelf almost hidden) and grabbed one to try out. I know what they are designed for(NOT dimming lights), but I'll give my quick first impressions of them for use in our world. First thing I noticed, they feel cheap. I do like that it has a three position power switch: OFF, FULL ON and VARIABLE, so that the dimmer function is separate from the ON/OFF function. And this goes back to knowing what it's actually made for vs. what we're trying to use it for… It does not dim a lamp down to 0%(because I doubt that you would want to choke the power down like that to a router). I'm guessing I was able to go from 100% to 50%, maybe a little lower. This will probably be the deal breaker for me. There are times where we go very low, especially with pattern projectors(yes, I could swap out to lower wattage lamps, but that is a pain and sometimes I do need the punch). Of course I could be a 'baller' and just get a new LED Source 4… Lol. Or buy a purpose built for TV/Theater Magic Gadgets dimmer and spend as much as a lighting fixture for ONE dimmer. Not… There's been a single fixture MG dimmer sitting in a display case at my local Barbizon for AT LEAST 10+ years that no one will buy, because they are so outrageously priced for what they are.