"Steven Studio" HMI 1.2K Fresnel Light. at DVinfo.net
DV Info Net

Go Back   DV Info Net > The Tools of DV and HD Production > Photon Management

Photon Management
Shine an ever-loving light on you.

Thread Tools Search this Thread
Old October 29th, 2009, 12:17 AM   #1
Inner Circle
Join Date: Dec 2003
Posts: 4,476
"Steven Studio" HMI 1.2K Fresnel Light.

Following below are some notes I have written for this light kit for which there is currently no available English-Language user-documentation.

I am no lighting technician so my notes below do not assure effective operation of the system or safety for the operator.

Comments and additional information and in particular, safety cautions by lighting guys are therefore sought and will be most welcome.

The comments below are based on my own observations of one of these lamps recently purchased. I have published the notes below for the purpose of prompting purchasers/users to a need to educate themselves in the use and maintenance of all HMI fixtures, not to simply aquire or hire, then plug in and switch on.

I have taken the attitude that not to publish is more neglectful than publishing unauthorised notes which may be incomplete or miss an important detail.

Owners or users of the "Steven Studio" HMI and other lamps imported from China should conduct their own careful researches and observations and develop a best practice based on the best advice.



The unbranded 1.2K HMI Fresnel lamp kit vended by Steven Studio is generally patterned after the style of ARRI and similar HMI lights.

The lamphouse construction consists of two-piece cast aluminium ends, which carry channels into which a combination of aluminium extrusion strips and pressed aluminium sheetmetal as vented side covers, steel sheetmetal internal heatshields and supports, are inserted and secured by machine screws.

Finish is a blue paint coat over the end pieces and silver anodising for the sides with the steel support cradle and base sled finished in black.

The upper front endpiece carries a hinged holder for barndoors and fresnel lens.

The upper rear endpiece is a vented cover which includes a small metal loop for a safety lanyard, chain or cable.

The lower front and rear end pieces support a worm and roller shaft and plain shaft which actuate the spot and flood focus. This functions by moving the lampholder and rear reflector towards or away from the fresnel lens. Both shafts are also the lampholder support.

The lampholder is for the G38 mount type OSRAM 1200W/SE metal halide globe.

Spot and flood adjustment is operated by two knobs, one each at front and rear attached to a common shaft.

Within the lower lamphouse, there is a terminal strip for wiring, integrated with encapsulated circuitry from which the heavy current leads to the lamp emerge. These leads feed through a support panel and heat shield via loose fitting grommets.

On one lower side panel there is fastened a short lead and connector. On the opposite lower side panel is the local on-off switch.

A slotted base panel is retained by overlap of two side covers.

The lower screws which secure these side covers also fasten a steel base frame formed from welded metal rod and flat bar.

Ventilation is by convective airflow.

The lamp is powered by an electronic ballast unit which permits frequency selection for 50Hz, 60Hz and “Flicker free”. There is a red push-button power switch on the front control panel. Also will be found to the left of the push-button is what appears to be a 25A circuit breaker. Circuit breakers are not customarily used as an on-off switch and such use might cause premature failure of the breaker.

The lamp, connecting cord and ballast are contained in a purposed blue panelled industry style transit case of apparent good construction quality and appearance.


The lamphouse with barndoors, ballast unit, HMI lamp and supply cable will most likely arrive in the purposed transit case within a tight fitted cardboard box.

The lamp unit includes the support cradle already assembled onto the lamphouse.

A stand must be obtained separately as there is no stand included in the kit.

The components are comprised of :-

Lamphouse including, assembled fresnel lens, support cradle and barndoors frame.

Connecting cable.

Electronic ballast unit including mains supply cable with two-pin connector. (The purchaser must arrange supply and rewiring of a plug suited to the local mains power supply systems.).

To be confirmed - New HMI globe in box. I received an Osram globe in box. (Please do not throw away this box. As the globe should not remain installed in the lamphouse when it is to be shipped over long distances, the box remains the only safe enclosure for shipping the globe.)


It is recommended that purchasers unpack, then pick up the lamphouse, turn it over several times in several directions and listen carefully for the sound of internal fasteners or fittings which may have come loose during the sometimes violent stresses of shipping.

Then perform a visual inspection. Pay particular attention to the ceramic lampholder, its metal cradle and fasteners, for chips, cracks or excessive looseness.

The ceramic lampholders normally have some looseness between the two clamping components when the globe is not fitted.

There will also be some permitted looseness in the fitment of the sliding lampholder assembly on the rods which carry it.

Check the polished metal reflector. It should be found supported in a cradle of three ceramic hooks. The upper hook may have been sprung in a severe impact and the reflector partially dislodged. Avoid touching the polished metal surface of the reflector as any skin oils will become baked on and create a permanent stain.

Check tightness of all visible external fasteners including the two screws for each of the support claws for the barndoors assembly.

Check the tightness of the rear safety cable loop fastener.


Do not move the lamp when it is operating.

Allow plenty of time for the globe and the lamphouse itself to cool before moving the lamp or packing it into its transport case.

If the lamp fails, assume always that the globe may explode and wear appropriate personal protective equipment when troubleshooting or changing the globe.

Whilst the venting is louvred, this lamp is not intended to be operated in rain or under water sprays. Fluid spills or droplets might not enter the enclosure directly but may wick in along joints and cause the globe to explode or the ceramic components to crack due to shock cooling.

There is also a risk of lethal electric shock when moisture is involved. Do not assume the heat of the lamp will boil off small amounts of moisture. This may condense elsewhere inside the lamphouse, cause corrosion or conductive carbon tracks across insulation and make the lamp or the ballast fail.

Do not look directly at the operating lamp.

Do not operate the lamp if the fresnel lens door is opened, the fresnel lens is missing or cracked. The globe is a source of potentially harmful ultraviolet radiation. Furthurmore, in this state, there is no protection from debris thrown forward by a globe explosion.

Route the cables systematically and sensibly to avoid tripping hazards or the lamp being pulled to ground.

The lamphouse can become very hot and is a potential burn hazard to unprotected hands or skin. Loose flammable materials should not be directly mounted to the lamp as diffusers.

The lamp should not be placed and operated where flammable materials like curtains or foliage may brush against it.

Because of competitive costs, this lamp may become favored by some small or low-budget independent film makers and purchased outright, rather than rented.

Small or low budget projects often are supported by crew multi-tasking and may be populated by untrained onlookers or keen enthusiasts. All should be discouraged from approaching the lamp to assist move or operate it unless already properly trained in use of HMI lamps.


My personal preference for on-set crew maintaining or servicing a HMI lamp, would include use of a full mask capable of protecting head and neck from glass fragments moving at high speed, long sleeved welding gloves for hands. If possible, use a welding apron for protection of chest and abdomen, though for a 1.2K light this might be regarded as over-caution by some.

The lamp should be removed from set for servicing or troubleshooting.

Before the front hinged door is opened for repairs or globe change, the lamp should be positioned to face a natural shield like a wall to prevent any fragments of glass flying freely and injuring anyone else nearby.

Last edited by Bob Hart; October 29th, 2009 at 01:14 AM. Reason: correction
Bob Hart is offline   Reply With Quote
Old November 3rd, 2009, 05:34 AM   #2
Join Date: Nov 2005
Location: Sydney Australia
Posts: 1,570
I've been looking at these for a while. How noisy is this unit?

Is there also a flicker free setting on the ballast?
If the only frequency options are 50Hz or 60Hz that would exclude their use for high speed work.

Does this instrument use HMI or metal halide lamps?
Your notes mention both, by my understanding HMI and metal halide lamps are not the same. Going by the G38 base it's a HMI.

If it's a HMI then one note worth mentioning is if the lamp starts to flicker or appears to have a black mark at one end in the internal envelope it is time to replace the lamp. The manufacturers rated life seems pretty accurate and death occurs quickly.

The startup of HMI lamps occurs in stages and the transition can come as a bit of surprise as the lamp flashes up to a higher power level. This is normal and crew should be prepared for it.

Even instruments rated as hot strike should be allowed to fully power up and run for several minutes before powering down. Although not mandatory lamp life will be improved and these lamps are expensive.

Both lamps and all reflective surface must be kept fat free. If fingers do contact either a clean with an alcohol wipe is one way to remove all traces of body fat.

A few days ago we had a new lamp fail taking out a ballast or the other way around. Thinking maybe it was the ballast that had failed I tried the lamp head on another ballast. I now have two faulty ballasts and one very, very dead lamp. Advice I've been given is the Philips lamps perform better than the Osram lamps. Less noise and the hot restrike works better.
Bob Grant is offline   Reply With Quote
Old November 3rd, 2009, 06:01 AM   #3
Inner Circle
Join Date: Dec 2003
Posts: 4,476

The ballast is totally silent.

The lamphouse emits a soft tinning buzz but then I am also a bit deaf. Subjectively, I think the fans on the SI2K are louder during button-off and softer during button-on but this might vary from unit to unit.

There are three frequency selections, 50Hz, 60Hz and "flicker-free". I have not tested the "flicker-free" selection for lamp-head noise.

There is also a dimmer control knob.

The lamp I received was an OSRAM 1200 W/SE G38. The box describes it as a "metal halide display/optic lamp HMI".

I have not confirmed if Steven Fu normally supplies the Osram lamps or whether this was a one-off.

Interestingly, the same ballast is used for the 0.5K HMI and it is described as a universal ballast.

However it might not be workable to substitute a lower power lamp in a higher power lamphouse. There is an encapsulated electrical sub-unit inside the lower lamphouse, which might be partnered to the power demand of a lamp type to match that demand to the ballast.

With this lamp, my imagining is that if the globe itself burns its internal rail through and this falls across the anode?? and shorts out, the internal encapsulated electrics in the lamphouse might fail before the ballast does. The electronic ballast is not going to hum loudly like a transformer does when overloaded so there will be no warning other than a lamp not firing up. The ballast appears to have a 25A circuit breaker on the front panel.

Last edited by Bob Hart; November 3rd, 2009 at 06:14 AM. Reason: added text
Bob Hart is offline   Reply With Quote
Old November 3rd, 2009, 06:40 AM   #4
Major Player
Join Date: Jun 2006
Location: Shenzhen, China
Posts: 781
Originally Posted by Bob Grant View Post
Does this instrument use HMI or metal halide lamps?
Your notes mention both, by my understanding HMI and metal halide lamps are not the same. Going by the G38 base it's a HMI.
HMI is nothing but a trademark of Osram Corporation. All HMI bulbs whether Osram or compatibles like Philips are all metal halide technology.
Richard Andrewski - Cool Lights USA - RED #114
Richard Andrewski is offline   Reply With Quote
Old November 3rd, 2009, 04:53 PM   #5
Join Date: Nov 2005
Location: Sydney Australia
Posts: 1,570
is your unit the same as this: dragonimage ?
Bob Grant is offline   Reply With Quote
Old November 3rd, 2009, 06:20 PM   #6
Inner Circle
Join Date: Dec 2003
Posts: 4,476

The dragon image photo looks the same. The two online Chinese vendors invite offshore resellers on their eBay listings, so there may be a few around.
Bob Hart is offline   Reply With Quote
Old November 6th, 2009, 09:50 PM   #7
Inner Circle
Join Date: Dec 2003
Posts: 4,476

I managed to get a closer look at the dragon image light without my computer chucking a fit on the ground. It is the same product.

I also saw a genuine used near-new ARRI 1.2K light posted on eBay by a US owner.

It appeared very, very, similar, except for what looks like a Hobbs hourmeter by the power switch on the lamphouse and ARRI logo on the anodised side panel. It appeared there was something extra on the control panel of the ballast.

I am guessing the light manufacturer in China is an OEM which makes the light also in special production runs for ARRI to their spec or maybe ARRI buys them in as standard and upgrades them.
Bob Hart is offline   Reply With Quote
Old November 7th, 2009, 05:10 PM   #8
Join Date: Nov 2005
Location: Sydney Australia
Posts: 1,570
Thanks Bob.
The Chinese are masters at making exact replicas. It's not until you get down to the type of alloys used that you may find the difference between the original and the copy.

An elapsed hour meter should be pretty easy to add yourself and probably not a bad idea.
Bob Grant is offline   Reply With Quote
Old November 9th, 2009, 02:38 PM   #9
Regular Crew
Join Date: Jun 2004
Location: Hollywood, CA and Roma, Italia
Posts: 155
It's all in the materials used.

Bob, you hit that nail dead center!

Arri doesn't OEM anything from China (so its NOT the same lamp). The Chinese are cloning the Arri stuff.

I have visited China many times over the last 10 years, and they are excellent at copying main stream designs. Their failing is in the materials they use when they clone an item.

They also come up with some original designs/improvements on existing designs as well.

An outfit that furnishes event lighting out here in Hollywood just purchased some Kino clones that were not an exact copy, but more a design "based on" kind of thing.

There are made of aluminum, came with lamps, and have a wireless remote to control the on/off and dimming. Cost? $180 USD each. They purchased 10 units and are planning on getting more. So far, no issues with them and I plan on asking them to get me a half dozen the next time they order some.

I do not know the contact info for the Chinese company, but I will try and find out.
Enzo Giobbé
Enzo Giobbé is offline   Reply With Quote
Old December 2nd, 2009, 11:19 AM   #10
Regular Crew
Join Date: Oct 2002
Posts: 61
Any idea where to source the 4' 4Banks you mention in your post? Ebay has some clones for $750 but I'm liking the sounds of $180 much more!

If you find out anything, please let us know. Much appreciated!
Brian Broz is offline   Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > The Tools of DV and HD Production > Photon Management

Thread Tools Search this Thread
Search this Thread:

Advanced Search


All times are GMT -6. The time now is 08:53 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network