Build Your Own Metal Halide (Low Cost “HMI”) Fresnel – Part III

I got into this “Cool Lights” business of mine because I thought prices were outrageous on pro level fluorescent fixtures. You can see all over this site the manifestation of what I decided to do about it; starting with the Cool Lights video and ending with low cost fluorescent fixtures. Well, I’ve gotten the same feeling again on another lighting technology: HMI. I was searching for an energy efficient hard or point light source to complement our fluorescent Cool Lights Softlight Series product line and was learning about HMI as the natural solution. Crazy prices though and no good reason at this point to have them so high.

In the previous two articles in this series we talked about building your own metal halide fresnel for under $500 as my own way of educating the world on what’s going on with HMI’s, the ridiculous reasons they have been artificially overpriced and also as the introduction for my own Cool Lights Hardlight Series. I’m afraid it will take some serious re-education (and perhaps even de-programming) for some people to accept that it’s possible to offer “HMI” for the prices I will be. In this, the next-to-last installment of this multipart article I will talk about our progress on the metal halide Hardlights. In Part IV, we’ll talk about the bulbs we chose and their equivalents on the market…


As you will see in this installment, I have been up to far more than just building a metal halide fresnel from a used tungsten instrument. At Cool Lights, we like to educate people on the technology behind modern lighting and enable them to build something if they like. We also know that there are many people that don’t have the time or inclination to build something and would rather just get going on a video or film project and they need reasonably priced lighting. To that end, we also provide low cost solutions for those folks and we try to engineer them in a way that you don’t feel you’re sacrificing anything to use a low cost lighting tool. In addition, part of my job is de-programming you from the myths that you’ve been fed for a long time related to lighting gear and perhaps certain other professional video gear as well.

While it’s completely possible to duplicate what I did and build a metal halide instrument for under $500, the articles really served the purpose of starting the re-education process for the more skeptical among you that will surely believe that any of these solutions we are providing in the Hardlight Series (as well as the Softlight Series for that matter) are inferior and that’s why they cost way less than the existing products. You have really been brainwashed by the large manufacturers into thinking they have magic ballasts and bulbs that aren’t available to the public at large and therefore: (1). It’s impossible for you to build anything even close to what they can provide (2). It’s even impossible for another manufacturer to build a solution like their “special” one. (3). These magic ballasts and bulbs justify the enormous prices they charge for fluorescent and “HMI” fixtures. (4). Color rendering index is everything and is SO important that you should only use bulbs with Magic Magenta that were manufactured in Italy or Germany by special factories established for photographic quality fluorescent and/or HMI lamps.

Semi-Pro Lights?

In addition, many wonder why there isn’t a semi-professional line of lighting from the major manufacturers similar to the lower cost semi-pro cameras we’ve seen in recent years. I believe the main reason for this is that while there are many features to separate a semi-pro camera from a pro one (removable lenses, size of imaging CCDs, etc.) there are not enough features of a lighting fixture to separate a pro model from a semi-pro. Therefore, a more stripped down set of fixtures for a semi-pro line would not have enough “separation” from the pro versions to continue to justify the huge prices they charge. After all, what would really keep the “pros” from adopting the semi-pro fixtures once they catch on (and would the prices they charge for the semi-pro line really be so much less expensive than the pro versions)? It was this vision of a semi-pro market for lighting that helped motivate me on to establish Cool Lights USA.

You see, I believe that, eventually, lighting will follow much of the same progression we’ve seen in the camera market: while the pros still use pro cameras, they also have some semi-pro ones too (but how long did it take for them to acknowledge the quality level of the semi pro versions?). They’ll eventually discover there really isn’t much difference between a Cool Lights HMI Par or Cool Lights Fluorescent Softlight fixture and a Arri Sun Par or Kino Flo Parabeam. Especially as time goes on and we add more and more features to make what differences there may be today all that much less apparent in the future. The Emperor really isn’t wearing anything right now but if you tell him about it he won’t believe you anyway.

The Flying Spaghetti Monster?

In the meanwhile, as many of you know, I spend most of the year in China now as it’s the best place for me to do the R&D that’s helping to make some of the things we do possible. China is such a huge market for components, where better to prove it can be done for less. Yes, you’ve been lulled to sleep gently by the songs of Arri, Mole, Lowell, etc. The songs of the Land of Magic Ballasts where the Flying Spaghetti Monster in league with the Bulb Wizard keeps everyone from entering except those with “the Knowledge” of those “Special Components.” Components like reflectors that are more reflective, special aluminum that has more “alu” and less “minium” than other fixtures, bulbs that are more bulbous and of course, more “balsy” ballasts. All these analogies seem kind of silly? Well that’s how the established manufacturers pricing structures and reasons behind them look to someone that’s acquainted with engineering, components, etc. Just plain silly–there’s actually not any magic going on inside these things.

Let’s all say together: “I was wrong. It’s not always the case that something has to be expensive to be good and it doesn’t always have to be manufactured in Germany either.

Yes, I can find just about anything I want here and if I can’t find it I can have it made pretty reasonably. You can think of China as the “Great Equalizer.” They don’t have a Statue of Liberty as such, but there’s an implied one that would have an inscription like: “Come one, come all, tired or full of energy, race and creed are irrelevant, you can find anything you need here; just bring enough money to meet our minimum order quantities!”

Goals for the Hardlight Series

As the first step in establishing the Hardlight series, I embarked on finding some existing fixture bodies to shorten our development cycle. My goals were well thought out. I wanted to offer fresnels and pars in the Hardlight Series and I wanted to do it with some general guidelines:

– mass-produced fixture bodies and accompanying accessories that are already well-known and recognized by the market

– fixture bodies available at the lowest cost thanks to their common availability

– reasonably compact units for the sake of portability

– locate the factories that produce the desirable fixture bodies for the pars and fresnels, make deals and specify changes

– use standard and well-known types of bulbs and sockets

– build prototypes to prove we have the best design before manufacture

– find the sources of the “magic ballasts and bulbs”

More specifically, my goals for the first fixtures in the Hardlight Series were:

150w Metal Halide (MH) Fresnel

575w MH Fresnel

150w MH Par

575w MH Par

1200w MH Par

All fixtures should have accompanying accessories such as barn doors, stand mounting hardware, interchangeable lenses for the pars, UV shielded lenses on all instruments and small and compact whereever possible using very sleek, cast aluminum designs for the sake of strength and heat resistance. Ballasts should be as quiet as possible. Bulbs should have the longest life possible. The fixture should use standard ballast and bulb types to allow you to use Cool Lights bulbs or Osram, Philips, GE, etc. if you so prefer. Carrying cases should be available or standard on the more expensive models. As you’ll see in the following chronicle, some things got changed along the way but the basic goals stayed the same.

The Pars

So, what separates a par from a fresnel–what is a par anyway? Really, a par is an “abbreviated” spotlight. Several different stage/studio instruments all use the same “ellipsoidal bulb/mirror placement at their heart but with different lenses and other options. It’s the lenses and other options that separate them from each other. When you think of a par, think of a flash light or a car headlight. You have an ellipsoidal mirror with a hole in the center through which the bulb peaks through. The bright shining point of light in the center of the mirror in combination with certain lenses gives you the par light.

The crudest par instrument in the stage and studio lighting arsenal is the “par can” which comes in many different sizes. Its not a problem to use tungsten with these simple instruments as the dangers from open face halogen are relatively minor compared to those of a metal halide instrument (exploding bulbs, UV emitting, etc.). While some manufacturers have used this body for a metal halide par, I personally wouldn’t do it–its just not safe enough for my liking. So when I embarked on this mission, to find the ultimate fixture bodies for my par models, there were several criteria I went by. Number 1: I wanted cast aluminum body for strength–to stand up to both the heat and potential bulb rupture. Number 2: I wanted changeable lenses for differing effects.

My first stop was one of my existing manufacturing partners where I know their inventory of fixtures pretty well. They had a commonly available, cast aluminum, attractive par fixture that I believed would be perfect, at least for the lower wattage pars. I’m not talking about some cheap, pressed metal “par can” here.

This is a relatively thick aluminum, tough fixture with a great ellipsoidal or par type reflector and bulb arrangement and has an interchangeable lens set as well. I ordered my first prototype with a G12 socket to try out a simple 5300K (CRI 80) single ended metal halide bulb and ballast combination I obtained. The effect was beautiful. Absolutely, a stunningly bright, 13,000 lumens worth of light streaming through my workshop area giving some of the nicest looking, focused, shadow-casting hard light you can find. In addition, as anyone who has worked with HMI or metal halide will tell you, that while the bulb and fixture become intensely hot during operation, the light that is cast from the fixture is a “cool” light. If you built my metal halide fresnel in the last two parts of this series, take that instrument along with a 650 or 1000 watt tungsten fresnel and place them side by side.

A Cool Light?

One thing you’ll instantly notice as you walk into the light of one or the other of the two fixtures is the amount of heat in the beam from the tungsten fresnel and the lack of heat in the metal halide one. In addition, if you want the same strength of instrument to try this exercise out on, choose a 250w metal halide fresnel and a 1000w tungsten fresnel for the best comparison (or alternately a 150 MH and 650w tungsten). At 86 lumens per watt (LPW) or so, the 250w metal halide is putting out about 21,000 lumens of an uncomfortably bright, but cool light usually of “daylight” color temperature. It’s drawing 250 watts and definitely radiating 250 watts of heat from the fixture itself (which acts as a heat sink for the bulb) and also some very mean ultraviolet radiation too that we hope is being filtered by the lens of our instrument.

On the other hand, the tungsten model is drawing 1000 watts to put out 20,000 lumens assuming the best case of 20 LPW. It’s light is not only very “warm” in color temperature but uncomfortably warm to bask in too. Guess what else? The tungsten model is only available in, a “tungsten” color of 3200K; but our metal halide version is available in a tungsten color as well as the more well-known daylight color too. These are most of the reasons I so appreciate this techology. It is the “fluorescent” of hard lights and its really hard to find a more efficient hard / point light source at this time than metal halide. Anyway, back to our par prototype.

Moving up to 575w

After I got the 150w model working and learned a lot about what changes I might want to make, I set about changing it to run a 575w, pro-level, HMI clone bulb with a G22 base. This bulb has hot restrike capability and I acquired an relatively inexpensive, hot restrike, 575w electronic ballast. I quickly figured out though the changes necessary to the bulb/socket area of this fixture would be enormously expensive though to accomodate the relatively huge G22 HID type socket. What this meant was we probably wouldn’t be able to do hot restrike with this particular par body, but we can run a GX9.5 base 575w cold strike (non-hot restrike) bulb. We can still have our 49000 lumen, 575w light, but we just have to wait a couple of minutes after we turn the fixture off before we can expect it to relight again. Inconvenient, but not the end of the world. At this point, I realized it would make the most sense to have an “economy” line of cold restrike and non-dimmable fixtures and a more “premium” line with those more advanced features; but even the premium line should be priced way under current “HMI” pricing. Target price for this unit is $699 with set of 3 lenses, barndoors, ballast, lamp cable and non-hot strike bulb. An extremely good value! We came very close to my original target price of $599 with this model only off by $100.

The SportLight 575w

SportLight 575

When I realized I wouldn’t be able to offer one do all, 575w fixture because of the socket issues, I set about trying to find another option with a G22 socket for another 575w model par. I was also searching for our 1200w model and was beginning to believe I might need to create a new model, set of molds, etc. to make all these ideas happen when I found what I call the “SportLight” 575w from another factory here in China. It’s got most all of what I was looking for and will be an ideal offering once a few small changes are made to it. It also has classic looks like many other portable 575w versions and one thing I really appreciate in a par: a focusing mechanism to move the light further into and out of the reflector.575w Par with Lens and Barndoors

On a par, this focusing has a bit different function than in a fresnel. The further back into the unit the bulb goes, the further out of the reflector and voila, you have dimming without color temperature change! This, in combination with the dimming to 50% available on the included electronic ballast means you can change the intensity to around 15% or so which is very rare for a metal halide instrument unless it has a similar mechanism. In addition, the back part is removable and could have a protective glass beaker offered as a future accessory which would allow the fixture to be used in a lantern configuration with a space light or china ball type diffusion arrangement.

The LensesThe SportLight is about 17″ long from front to back and includes a built-in safety lens and a set of 3 easily changeable lenses (wide angle par, narrow angle par and diffused–that just slip right in front on the accessory holder) and safety cables to attach to pipe grids or the lenses to keep them from falling. Also includes a hot restrike ignitor and ballast and of course, barndoors. We’re in the process of developing a special custom road case just for this light to keep it in good shape while you’re traveling. This will include a trolley with pull up handle for extra convenience. The SportLight Ballast

The ballast (about 13″ x 6″ x 3 1/2″ and weighs 2 lbs) is not completely noiseless as it has a fan, but we are including a 30 foot lamp cable to allow you to place the ballast a distance from where the action is taking place (and open microphones will likely be). The target price for the SportLight 575w is $1999 with all these accessories included. Quite a ways from my original target of $599 to $899 for the 575w model but then this has a lot of features and the craftsmanship is incredible. In addition, even at this price, it is still way under such pars as a CNC 575w or even a K5600 400w model but has many of the same features that come standard where these manufacturers charge large premiums for extra accessories.

Here’s one last view of the SportLight with one of the easily changable lenses and barndoors. Quite a beauty!

SportLight 575 with Barndoors and Lens

The Elusive 1200w Par

HMI 1200w ParOf course, as you know, I also have a 1200w par on the list and was actively looking for a solution there too. As it turns out, there aren’t that many par fixtures around that would be suitable for the extremely hot 1200w metal halide “HMI” type bulbs. Most engineers I talk to tell me it’s very hard to make a portable 1200w solution since the fixture must act as a heat sink for the bulb; thus, you need a lot more fixture to keep the bulb life as long as possible. All the same, I am determined that it should be as small as possible. The lens should optimally be a 12″. Unfortunately, we still don’t have the ultimate low cost solution for the 1200w model other than this one model I found pictured here. It uses a fresnel type body and a different front with larger safety lens and par reflector. For sure, it can be offered more reasonably than most 1200w pars (around $2600 with electronic ballast, bulb, barndoors and 1 extra par lens) but still not in the price point I want to offer and not at the level of portability I would like either. I was originally shooting for around $900 to $1400 and I’ll continue that quest. I eventually get what I want because I don’t give up easily.

Fresnel Prototyping

Original 575w fresnel prototype

In the meanwhile, during this same period, I was also searching out for fresnel bodies to use for the fresnels of this series. I had an idea early on that I wanted to use the famous “blueline” models that are floating around the market. These are super attractive, compact models that just seemed to be the natural choice for my metal halide fresnels. It took a while to find the factory that made them here in China but while I was searching I found at least on other model I evaluated to be the 575w fresnel in our series. It started its life as a 1000w tungsten model with a G22 socket so there really wasn’t so much modification to be done. The socket was a tungsten model (yes there are special HID versions of many of these sockets to withstand the high voltages of the starting pulses of metal halide bulbs) that would work for the 575w G22 base bulb for temporary prototyping with no problem–it just isn’t a long term solution though. Also the mirror needed adjusting as the center or point of light in my metal halide bulb was different from the 1000w tungsten bulb this model was made for. Again, it could work without the adjustment and adaptation for my metal halide bulb but that is not an optimum solution.

The result was okay but not great especially from the standpoint of size–the lens is an 8″ and it just seemed so big and bulky. In addition the barndoors were a bit flimsy and the lid on the front for accessing the bulb compartment wasn’t totally fitting correctly. One thing I really loved about it though were the super well-defined shadows it put out. Just what we love in a fresnel: for instance, the ability to close the barn doors to a rectangle and you get a very sharp rectangle of light on the wall. It really has a great lens and focusing mechanism. This concept is being lost somewhat more and more as some newer fresnel lenses are incorporating varying degrees of diffusion which I think is a big mistake. We need at least one instrument in our repertoir that puts out clean shadows with sharp edges. You simply can’t depend upon a par for that. The fresnel is classically used in those instances where we want clear shadows and many of these more modern fresnel lenses just aren’t what they should be.

We talked a bit about what a Fresnel is in the last part of this series. Let’s look inside of one of our new models this time though and see the differences.

Inside a Fresnel

Inside the 300w ModelI was ecstatic when I finally found one of the factories making the models I really wanted. Available in 150w, 300w, 650w, 1000w, 2000w and even 5000w models. I chose 300w, 650w and 1000w sample models to experiment with. The clunky 1000w black model above was relegated to the junk closet. I broke open the 300w first because I had high hopes for putting our 150w G12 bulb in that. No go. Just too small. You can see in the picture at the left the innards of one of these 300w units.

Basically, operates just like all fresnels: the sled that moves back and forth with a screw drive mechanism operated by a focusing knob on the back of the unit; a mirror and in front of that a socket for the 300w halogen quartz bulb both mounted on the sled. Moving the sled back farther from the lens makes the light narrower and moving it towards the lens makes it a wider beam. Optimally, the point light source of the bulb should be exactly in the center of the mirror. The lens is, well, a fresnel lens–that’s why we call it a fresnel. Anyway, back to our product development.

All the models of fresnelsMy 150w metal halide bulb was quite a bit taller though than the 300w halogen so it would take major modifications to this model to make it work. Doable perhaps in the future but not for now. I next chose the 650w model to modify for the 150w bulb. This was doable; as is using a 575w G22 bulb in the 1000w model. Now, it’s just a question of getting the factory to modify them to my specifications. As a further incentive to the factory and to our customers, I came up with the idea of offering the tungsten line as a special order item (non-stock for the most part).

So why would a company named “Cool Lights” offer tungsten fresnels? Can you imagine one of these with “Cool Lights” on the side? I couldn’t, so I never had this plan before; but I thought of the idea when I was planning for buying the quantities necessary of fresnels that we would need to buy in order to keep the costs low and therefore offer the target prices I wanted to. If I bought the quantities of metal halide fresnels necessary it would be a really expensive order because we would also have to buy the corresponding amounts of ballasts and metal halide bulbs too. That’s when I thought of offering the tungsten models as well. The factory 150w tungsten modelsdoesn’t care so long as we buy the quantity of fixture bodies necessary to make it worth their while to manufacture them. So we order a certain quantity of 650w and 1000w models and some are planned to be metal halide and some will be tungsten. We’ll even offer the rarer, tiny tungsten halogen 150w (as well as the more common tungsten 300w too) “pepper” models pictured on the left which find so many uses that they have a place in practically any kit.

Seems a win/win situation for everyone involved, especially our customers as we’ll be able to offer these tungsten versions for quite a bit less than they go for in the USA now. In addition, we’re making changes to them that seem worthwhile and almost intuitive. For instance, we’ll offer them with an IEC plug adapter on the back so it’s easy to change the power cord from one country to the next. Also, a handle on the back of the unit to keep you from burning your hand while adjusting the fixture angle. Color of the front and back of the unit will be black for the tungsten models and dark green for the metal halide versions. Barndoors will be included with all models and the metal halide ballasts will be universal voltage to work anywhere in the world.

Target prices for the 150w and 575w metal halide fresnels will be $399 and $699 respectively and will include the barndoors, ballast, lamp cable, and one bulb. With the 150w model, you’ll have a choice of 3000K or 5400K. On the 575w fresnel and par you will get a bulb in the range of 5600K to 6000K included–details on that to still be worked out.


We’ve been very busy trying to fulfill our goals and promises. These fixtures should be available in the September timeframe. Keep watching on the site for special offers and pricing. We have a new and interesting pre-order reservation process which we will be trying out soon and I’ll describe in more detail as we get all those offerings ready. This will be a very unique opportunity to, once again, do things differently from all the other manufacturers and provide even further savings for those that choose to participate.

In the next and last installment, I will talk about the bulb choices using Osram as the reference and then showing some equivalents available–all to underscore our committment to using only standards and not proprietary solutions.

(c) Copyright 2007 All rights reserved. May not be used in part or total without the express permission of the author in writing. Waiver of damages:This information and all included material are provided as is, and Cool Lights USA can not under any circumstances be made responsible for any damage, injury or losses caused directly or indirectly by implementation of the information in this article.

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