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-   -   Afordable Chinese HMIs (https://www.dvinfo.net/forum/photon-management/62817-afordable-chinese-hmis.html)

Richard Alvarez March 17th, 2006 08:06 AM

SO Underwriters Laboratories has not put the seal of approval on them. Wonder why. Wiring is probably sub standard. You're talking a LOT of amps, so it's possible their wiring isn't up to US code, or they don't have a circuit breaker. Something like that.

But I'd like to know what their price range is, and what it would take to get them up to grade. I suspect you'd have to import in mass to get the price break.

Vincent Rozenberg March 17th, 2006 09:15 AM

I've send an email to the German guys regarding prices. I'll keep you guys posted!

Boyd Ostroff March 17th, 2006 09:42 AM

Quote:

Originally Posted by Richard Alvarez
SO Underwriters Laboratories has not put the seal of approval on them. Wonder why.

There may not be any problem with the fixtures, but the manufacturer may not be willing to go through the full UL qualification process which I gather is very time-consuming and expensive. This is why so many consumer electronics products use external "bricks" for power. That way they can use an existing UL-approved power supply and skip the approval process on the device itself since it doesn't plug directly into a wall outlet.

A little OT, but amusing anyway. Was recently talking to a theatrical lighting designer who did a big production in China at the "Great Hall of the People" (or whatever). She said they had to allow a full afternoon for the fire dept to test their entire lighting rig. All the pipes had to be lowered to the floor and each instrument was examined and tested with temperature probes to insure they were within specs; she'd never seen anything like it before! So if these HMI fixtures are used in China they might actually exceed our own US specs...

Bob Grant March 19th, 2006 02:28 PM

Got a reply to pricing on the 200W HMI, roughly USD 1,500 for a full kit.
Interestingly these lights can be run off battery, the battery goes for just under USD 1000, that may include a charger. No info as yet on how long the battery will run the light.
The design looks very similar to the Joker Bug from K5600. but way cheaper.

Vincent Rozenberg March 19th, 2006 03:04 PM

That's a very good price! Looking forward to some hands one experience if possible. Don't need it right away but maybe if I do I'll ride down to Germany to test out.

Ralph Keyser March 21st, 2006 04:18 PM

Hmm. Reading too much too fast I guess. I was thinking about something like the Joker Bug setup that lets you use an HMI fixture in a Chinese latern. Apologies. At least the thread holds together better :-)

As for the PAR terminology, it may be "old style", but the intergrated lamp/reflector/lens design is still very much alive and well. If you can separate the lamp and the reflector and the lens, then I sort of want to call it something else. Maybe it is just symatics.
I'm sure that ETC is going after the traditional PAR can with their swapable lens design, but their naming convention is a little confusing to me. I haven't seen their "PAR" show up much in film lighting but maybe they will. They seem to be pretty efficient instruments. The Source Four, meanwhile (the ellipsoidal one), is the Xerox of the ellipsoidal world. People say Source Four instead of ellipsoidal. Carrying that name into their can design seems confusing.

Alexandre Lucena March 22nd, 2006 05:47 AM

on the cheap side
 
Dear People

What about an automobile xenon as a day light source. It should work.
1 Its colour temp. is over 5000k
2 It comes in sealed PAR unit
3 It has a portable small balast
4 One could run it out of a car battery or out of a cars engine.
5 getting someone to seat in front of the cars xenon beam
and shoot some test should not cost an arm and a leg.

my 2 cents

Alexandre

Henry Gretzinger March 22nd, 2006 08:16 PM

Alexandre:

I've tried this already, as a matter of fact. Here are the problems:

1) Many automotive Xenon or Metal Halide lamps burn at 10,000k. That would be fine, save for the fact that you'll lose about half of the lamp's output trying to bring the color temp back down to 5600k (with 1 + 1/2 CTO)

2) While the ballasts are electronic, they're not flicker-free and produce quite a bit of noise. I've shot tests with the DVX100 in 24p and it's not pretty...

3) Low wattage. 30 to 125W. Good for an eyelight I suppose, but losing half of your already insignificant punch to color correction is a bummer.

That said, I'm looking into building a daylight maxi brute-type fixture with automotive bulbs. Could be very useful if you're looking to add a little ambient light to an exterior location...

Henry

Richard Veil March 23rd, 2006 10:19 AM

Go find China lights if you want
 
but I would check out www.k5600.com

all you need is ballast problems and your screwed

plus see if the chinese are still using Magnetic ballast..

it that what i am looking for.. Magnetic.. correct me dv team

they are unrelyable and no one uses them anymore.

electronic ballast very important should you need repair

mole Digi Light hmi also nice

r

Ralph Keyser March 23rd, 2006 01:41 PM

Magnetic ballast
 
I don't think any of the major brands use magnetic ballasts anymore, but there are certainly a lot of them still in use, especially at lower budget rental places. They are very heavy, inefficient, and often noisy along with some flicker problems but they do work. It's still an excellent point to check out, however, since magnetic ballasts are cheaper to manufacture than electronic ones, and the ballast is a significant portion of the cost in an HMI.

Richard Veil April 6th, 2006 04:40 PM

I like www.k5600.com
 
Many of their kits have Chimera Lanterns.

The lights K5600 make are great. Some AC capability as well.

r

Bob Grant April 7th, 2006 04:16 AM

Magnetic Ballasts
 
As far as I know these are more reliable than electronic ones, there's almost nothing in them to fail. But they are heavier. Still used in cinema projectors, weight doesn't really matter in this case. Flicker level should the same, HMIs run on DC, around 80V. For lower power HMIs electronic ballasts are pretty much standard fare but over 10KW, I think you'll find mostly magnetic ballasts. I don't know if electronic ballasts are any quieter either, once the power level goes up they can get pretty noisy and it's pretty high frequency noise, they're also more likely to produce interference due to the fast rise times in the high current switching circuits.

The Chinese HMIs we've been talking about do use electronic ballasts.


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