Coollights HMI 575w series question
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Cool Lights
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I'm running out the door to catch a plane so I don't have time to give the detailed answer this deserves but I will pick this up later...
Macville
Well-known member
According to all my research, along with many discussions with Richard, a 575 won't do much in direct sunlight. Even a 1200 PAR isn't going to compete that much (especially when you defuse it.) It seems that a 4K is more what you need. Of course, this all depends on how you are using the unit (outside in direct sun vs inside to bring up levels to equal out light coming in windows, etc.)
A PAR has a more efficient reflector than a Fresnel. Therefore, at the same wattage the PAR will produce more light--of course it's not as focusable (you have to switch out PAR lens for different focus.)
Matthew
A PAR has a more efficient reflector than a Fresnel. Therefore, at the same wattage the PAR will produce more light--of course it's not as focusable (you have to switch out PAR lens for different focus.)
Matthew
puredrifting
Major Contributor
Matthew:
You are correct. I did a shoot at Disneyland in bright sunlight and we ended up needing a 4k HMI to key with and we used 1200 watt PARs for rim/hairlight. I normally never would shoot in bright daylight but that was what the client wanted to so we did it. A 575 watt HMI will be close to useless in bright daylight. In shade, might function marginally.
If I would have had more time, reflector boards and a butterfly would have worked better but the rigging time is longer and I didn't have the time.
Best,
Dan
Macville
Well-known member
How did you use the sun in that case? Side, front, or helping with the hairlight in the back?
Matthew
puredrifting
Major Contributor
Hi:
Sun as key, 4k as fill and two 1200 watt PARs as hair/rim. Looked pretty good, if I do say so myself. We shot all of the footage, then the client "decided to change directions in the video based upon a new Disney dictate that kids don't like to see younger kids in videos, they only want to see tweeners and teens" Whatever.
Dan
Macville
Well-known member
I'm guessing that you had a wider shot instead of a close up to need a 4k as a fill. Pretty impressive.
Matthew
Cool Lights
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Let's start with the original question. So much of manufacturing is being able to control the costs of ALL the parts that go into a unit. The more parts you control down to the lowest cost possible, the more it is possible to either profit or pass the savings onto customers. Of course, as you can see with most of our fixtures we do the latter. In the case of the CL-MP0575 575w "Sportlight" par I don't (unfortunately) control all the parts. We found the fixture in China and the maker is very "proud" of it. I still wanted to offer it though. We are having it modified over the way I found it though. The original ballast and ignitor combo, while darn reliable was super noisy so we are dealing with that issue. Next, we are changing the reflector because the one he used in the original is not that great and could be much better. My new prototype puts out a bit more light than the original thanks to the new reflector. Lastly, we will add a proper ballast to head cable on the lamp like we've done on our other products like the CDM 150 and the MF0575 Fresnels. One thing I really liked on the original model that you don't see too often in PARs is a focusing mechanism that can retract the bulb into the reflector. This acts somewhat like a mechanical dimming feature. Considering you cannot dim any HMI bulb beyond 50%, to dim further than that requires a trick of some kind--usually mechanical and this is an example of that kind of thing. Very nice. The par also comes with the lens set so that work is already done and it is a very well done and usable set too.
Next question. What is the difference between the fresnel and par? The main difference between any fresnel and a par is usually the reflector / bulb configuration and lenses used. First of all, both are in the "spotlight" class of film or video lighting. This means they produce a round and fairly good beam. A par (stands for Parabolic Aluminized Reflector) has the most efficient kind of reflector you can find: parabolic. The bulb usually sticks through the middle of the reflector and the actual point of light should be optimally in the sweet spot of the parabolic reflector to be the most efficient. An HMI par will usually have available a safety lens to protect from the heat of the bulb as well as a set of lenses which will usually contain a wide beam, narrow beam and diffused lens. These lenses should be easy to put on and take off usually on some kind of accessory holder or snap in type.
The fresnel isn't too bad but the reflector configuration is never the same. You basically have a mirror and the bulb posed in front of it all on a focusing sled. Then in front of all this you have a fresnel lens which is fixed and not easily removable or interchangeable with other lenses. The fresnel is a very "utilitarian" device that puts out a good amount of light, but given the same wattage, same bulb, same ballast--the par will generally be stronger thanks to its reflector. People will describe the HMI 575w Par to be brighter in other words than the equivalent fresnel of the same wattage. Fresnels are still very usable though.
On the other comments. Everyone's right on. A 575w (even the par) won't do you much good outside. It'll quickly be overpowered by the sun. I think of the 575w as a good indoor light for equalizing daylight coming into the room although a 1200w may be needed in some situations where there are a lot of windows and you can't ND them.
A 1200w may be usable outdoors with some good overheads but the 4000w is generally thought of as the minimum for most outdoor work as Dan pointed out.
It all depends how wide a shot you need to fill. A 1200 par will fill a medium shot nicely. I have used two 1200 pars together thru a diffusion frame with a 12x12 grifolyn or a 4x8 foam core bouncing sunlight and it will do a nice job if your shot is not too wide. If your shooting backlit to the sun this combo looks awesome.
Richard will your 575 work like a bug lite with a bare bulb in a chimera?
Richard will your 575 work like a bug lite with a bare bulb in a chimera?
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Cool Lights
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Hi Robert,
Not yet. We need to engineer a glass beaker protection around it to be safe and that'll cost a bit of money to not only make the mold but also to make the minimum first order quantity of them. Unless of course we happen to find such a beaker existing but thats difficult. Its such a specialized item and really has to be durable and stand up to the heat of a 575w bulb.
Not yet. We need to engineer a glass beaker protection around it to be safe and that'll cost a bit of money to not only make the mold but also to make the minimum first order quantity of them. Unless of course we happen to find such a beaker existing but thats difficult. Its such a specialized item and really has to be durable and stand up to the heat of a 575w bulb.