What is the equivalent of a 2.5HMI to tungsten

L

leaftors

Well-known member
I don't have access to a 2.5hmi so how much tungsten would i need to produce the same amount of light. I'm also placing CTB over the tungsten lights.
 
actually with full CTB it is worse than that. HMI's are far more efficient than tungsten. A 1.2 give you nearly as many foot candles as a five K with both lenses clean. A 2.5 is about 3/4 the footcandles of a 10K. Now add that CTB. Ouch!

This chart may help. Notice the efficiency at distance varies.

Head 12ft. 15ft. 20ft. 25ft 30ft.
575 HMI 200 89 50 32 22
1200 HMI 600 267 150 96 67
650 Tweenie75 33 19 12 8
1000 Baby 150 67 38 24 17
2000 Junior500 222 125 80 56
5000 Senior356 200 128 89 50
10k Tenner 533 300 192 133 75
1k Mickey 150 67 38 24 17
2k Mighty 300 133 75 48 33
4x4 Kino 32 14 8 5 4
2x4 Kino 16 7 4 3 2
 
phudsontx said:
actually with full CTB it is worse than that. HMI's are far more efficient than tungsten. A 1.2 give you nearly as many foot candles as a five K with both lenses clean. A 2.5 is about 3/4 the footcandles of a 10K. Now add that CTB. Ouch!

This chart may help. Notice the efficiency at distance varies.

Head 12ft. 15ft. 20ft. 25ft 30ft.
575 HMI 200 89 50 32 22
1200 HMI 600 267 150 96 67
650 Tweenie75 33 19 12 8
1000 Baby 150 67 38 24 17
2000 Junior500 222 125 80 56
5000 Senior356 200 128 89 50
10k Tenner 533 300 192 133 75
1k Mickey 150 67 38 24 17
2k Mighty 300 133 75 48 33
4x4 Kino 32 14 8 5 4
2x4 Kino 16 7 4 3 2
Click to expand...

Is this chart yours or did you get it from some place... and if the latter... where?

Finding these things out by comparing manufacturer's specs is tedious at best....
 
Noob question: Are HMI's dimmable like tungsten?

Second noob question: What's the most powerful HMI that will run out of a standard socket without causing imminent death for those nearby?
 
1) No. Ballasted lighting instruments may have their own dimmers, but you can't plug one into a dimmer like you can with tungsten.

2) Depends on the wiring, and on the HMI unit itself, but with fully up-to-code modern wiring, usually a 1.2K. I wouldn't have much of anything else plugged into the same circuit, though.
 
David Jimerson said:
1) No. Ballasted lighting instruments may have their own dimmers, but you can't plug one into a dimmer like you can with tungsten.

2) Depends on the wiring, and on the HMI unit itself, but with fully up-to-code modern wiring, usually a 1.2K. I wouldn't have much of anything else plugged into the same circuit, though.
Click to expand...

Arri has an 1800w that can be powered off a household 20amp circuit. It's pretty sweet!
 
RyanT said:
Arri has an 1800w that can be powered off a household 20amp circuit. It's pretty sweet!
Click to expand...

Some HMI's with solid state ballast can be dimmed, albiet only about 20-30 percent. The dimmer is located on the ballast.

The Arri 1.8K can be run of household circuits but be prepared to spend a lot.
 
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David Jimerson said:
But can it be run on a typical 15-amp circuit? I'd be very wary.
Click to expand...


Weighing in at 1800 W vs. the 'calculated' 1800 W 15A @ 120V line... I wouldn't... If the HMI looks in any way like a 'capacitor' during startup, there will be an over 1800 W draw potentially, and trip the circuit breaker... at least that's what it's supposed to do...

My personal experience in this sort of thing is in regard to strobes, which are essentially big banks of capacitors, and having tripped breakers, or watched surrounding lights dim, while the power pack is recharging...

For me, probably 1200 W draw would be the most I'd put on a 15 A US house circuit.
 
phudsontx said:
No, it will not reun on a 15 amp circuit safely but it will run on a 20 amp circuit. This thread at Reduser may help.

http://reduser.net/forum/showthread.php?52058-Anyone-used-the-Arri-1800w-Baby-Max-yet
Click to expand...

That's what I would figure (though not being familiar with that specific instrument, I thought I'd ask), so if you're going to use it, you have to be sure you're on a 20-amp circuit -- and that's not typical. Maybe in kitchen outlets, but not in most other rooms.
 
Ok more noob questions:

1) So the only way to reduce the output on an HMI (if there's no dimmer on the ballast) is to toss some scrims on it right?
2) (super noob one here) when you guys mention only one per circuit, does that equate to one per outlet? I'm assuming there's a different meaning and that multiple outlets run on a single circuit. If that is indeed the case, how do you determine what's on the same circuit and what isnt?
 
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