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How to make a light flicker


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Hey,

 

Im sure this question has been answered somewhere but I can't seem to find it....

 

Anyway, I was wondering what I would need to do to make a light flicker intermittently (sort of how old lights would flicker and NOT a continuous HMI flicker).

 

Although it would be quite dangerous could I achieve it simply by connecting the wires back and forth by hand.... what would be a safer method?

 

 

THANKS IN ADVANCE!!!

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Magic gadgets makes an effects dimmer called the Flicker 2D. 2k watts on the base model, 16 different flicker patterns.

One can be bought for around $600, but I'm not sure about the rental rate. Indierentals in CA has it for $60. The manufacturers website is: http://www.magicgadgets.com/mg_ol_04.htm

 

That might be a better option then the manual route - that way you lower the risk of electric shock and have your hands free for other things.

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Although it would be quite dangerous could I achieve it simply by connecting the wires back and forth by hand.... what would be a safer method?

 

Er no! I don't think that would even get the effect you want and you could get that effect by just turning on and off the light very quickly at the switch. (The switch basically works the same way without exposing you to the wires!)

 

Apart from that, this would be a very bad thing to do because it's not just yourself that would be put at risk by messing with live wiring in this way. The cast and crew are also people don't forget!

 

love

 

Freya

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What kind of "flicker" effect are you looking for? More like a TV flicker? Fire flicker? or lightning flicker? Set the scene and then we can help a bit more.

If you're looking for a tv flicker or a dimming effect, you can build a box dimmer (600 watt max) at lowes for about 30 bucks. You can get some really good looking dimming effects from this.

 

Oh, and please don't just touch the wires together. You could kill yourself or damage whatever lighting equipment you're using.

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What kind of "flicker" effect are you looking for? More like a TV flicker? Fire flicker? or lightning flicker? Set the scene and then we can help a bit more.

If you're looking for a tv flicker or a dimming effect, you can build a box dimmer (600 watt max) at lowes for about 30 bucks. You can get some really good looking dimming effects from this.

 

Oh, and please don't just touch the wires together. You could kill yourself or damage whatever lighting equipment you're using.

 

I considered the joining of the wires more of a joke then anything lol...

 

But the effect I am looking for is more like the flicker that occurs when turning on a Fluro light. The scene is in an old worn out shed and I want the light to flicker during particular parts in the script (when I want to convey a sense of fear). So the flicker should sort of look like the light is getting old and and doesn't really work well and perhaps flicker on and off every 3-5 seconds. Do I need to use particular lights to do this effect?

 

Thanks for your help so far guys!

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I'm not 100% on this, but building a floro light and putting it on a dimmer can really screw with the ballast to the point where this happens. Again I'm not 100% on if it'll work but I seem to recall having tried this once for a shoot, scrapping the idea (director changed mind 'bout it) and having it work for me off of one of the industrial, not the best anyway, bought at lowes, cheap, ballast/tube/dimmers.

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Right. Fluoros don't play well with dimmers; unless you're just going on/off. As far as I know there are no manufactured 'trick bulbs' to achieve this kind of effect. Perhaps if you were to put a bunch of plain old fluoro setups (as Adrian suggested) on seperate wall switches, warm the tubes up first and then switch them on and off (if i'm not mistaken this can be done with dimming, but again it needs to be on or off) and flip them at different times you could get somewhere close to the effect you're looking for

Edited by Ross Neugeboren
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Hey,

 

Im sure this question has been answered somewhere but I can't seem to find it....

 

Anyway, I was wondering what I would need to do to make a light flicker intermittently (sort of how old lights would flicker and NOT a continuous HMI flicker).

 

Although it would be quite dangerous could I achieve it simply by connecting the wires back and forth by hand.... what would be a safer method?

 

 

THANKS IN ADVANCE!!!

 

search for TV gag and fire gag and you'll get loads of results.

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Alternatively, if the load is less than 500W, wire a fluorescent starter in series with the incandescent lamp.

 

This works really nicely. One of my favorite flicker gags is this done with each of two or (better yet) three bulbs so the flicker never reaches zero output. With one the flicker effect drops too low in output and it's pretty obviously a gag.

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Another thing you can do that I forgot about is run a light through 2 dimmers in series. It's finicky and tough to control, though. You have to fiddle with both dimmer knobs until you get what you want. I think you're basically creating oddball electrical waves once the 2 unevenly dimmed signals are added together. It's a nice trick to know about but not the first choice of methods.

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Er no! I don't think that would even get the effect you want and you could get that effect by just turning on and off the light very quickly at the switch. (The switch basically works the same way without exposing you to the wires!)

 

Sometimes the solution is simpler then you first think!

 

Thanks!

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Another thing you can do that I forgot about is run a light through 2 dimmers in series. It's finicky and tough to control, though. You have to fiddle with both dimmer knobs until you get what you want. I think you're basically creating oddball electrical waves once the 2 unevenly dimmed signals are added together. It's a nice trick to know about but not the first choice of methods.

 

Hi Chris,

 

I'll have to come up with a way to create fluro flicker for my next shot, so are you saying you're putting two dimmers in series and a fluro at the end? Or is your idea feasible with incandescents only? And what kind of dimmers does one use? I tried one of my cheap homedepot dimmers on a fluro today. It started buzzing loudly and started coaling several components very quickly!

 

Cheers, Dave

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I'll have to come up with a way to create fluro flicker for my next shot, so are you saying you're putting two dimmers in series and a fluro at the end? O

 

Fluoro's don't dim - hence the bad things that happened when you tried it. If you really need fluoro flicker, perhaps two dimmable kino divas could work, though they do seem to fluctuate in color temp when you dim them.

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Fluoro's don't dim - hence the bad things that happened when you tried it. If you really need fluoro flicker, perhaps two dimmable kino divas could work, though they do seem to fluctuate in color temp when you dim them.

 

I'm trying to get the effect of broken fluros. I don't actually want to dim them, which would of course be possible quite easily with a dimmable high frequency ballast. Chris suggested the method I described for that kind of flicker if I read him correctly.

 

Cheers, Dave

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Hi Chris,

 

I'll have to come up with a way to create fluro flicker for my next shot, so are you saying you're putting two dimmers in series and a fluro at the end? Or is your idea feasible with incandescents only? And what kind of dimmers does one use? I tried one of my cheap homedepot dimmers on a fluro today. It started buzzing loudly and started coaling several components very quickly!

 

Cheers, Dave

 

Oh, no! Sorry, David. I should have specified that the double dimmer thing is for incandescent lamps only. Even then, it's a lsat choice. It's very finicky and difficult to dial in perfectly.

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Oh, no! Sorry, David. I should have specified that the double dimmer thing is for incandescent lamps only. Even then, it's a lsat choice. It's very finicky and difficult to dial in perfectly.

 

Ok. Dang. I may have to switch my practicals to bare bulbs then. Hm... Not as cool as fluros in this case, but workable. It's a dungeon type basement after all. Thanks, mate!

 

Cheers, Dave

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Ok. Dang. I may have to switch my practicals to bare bulbs then. Hm... Not as cool as fluros in this case, but workable. It's a dungeon type basement after all. Thanks, mate!

 

Cheers, Dave

 

You might try the effect anyway with a couple of the bare bulbs. A flickering incandescent doesn't really make sense logically, but it does look good and achieves an unease that may suit the space.

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I'm trying to get the effect of broken fluros. I don't actually want to dim them, which would of course be possible quite easily with a dimmable high frequency ballast. Chris suggested the method I described for that kind of flicker if I read him correctly.

 

Cheers, Dave

 

 

It doesn't work with the newer electronic ballasts on more modern fluros, but most gaffers I know carry a couple bad ballasts for exactly this. You simply plug them into your fluro light (prac) and instant fluro flicker.

 

If needed you can just source some older style fluro pracs and use expired ballasts in them.

 

jb

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Thanks John, thanks again Chris. I'll see what I can find!

 

Cheers, Dave

 

My Solution was just to get one of the crew members to flicker the fluro light by the switch. He had to perfectly find the spot which wasn't on, but wasn't off and just flicker between those two. Not ideal but it did the job.

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Ive rigged big sets of fluoro battens to dimmers (like 20 battens at a time) and dimming them produces a very distinct flicker but forget recording sound and I dont imagine its good for the battens but it works and you can control the speed of the flicker somewhat by controlling the dim amount.

Ive also put dodgy starters in ( a starter the gaffer had which he knew was broken) and that works great too.

I know he has a few in the truck maybe your gaffer does too?

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