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-   -   any reviews on these HMI's? (https://www.dvinfo.net/forum/photon-management/99181-any-reviews-these-hmis.html)

Ralph McCloud July 18th, 2007 06:55 AM

any reviews on these HMI's?
 
Has anyone used these HMI's from Image West? http://www.imagewest.tv/index.asp?Pa...PROD&ProdID=45

Would be interested to hear any reviews. Thanks in advance.

Tip McPartland July 18th, 2007 09:55 AM

Same as Alzo Digital: HID
 
These aren't exactly HMI, which is a trademarked term for a particular design of HID. These are very close, however and are HID which are arc lights with very similar characteristics. The color temperature is lower at 5300K vs. 5600K for HMI. Also the color rendition index is down at around 85 versus 95 for HMI. All that having been said, I have two of them (Alzo Digital brand) and like them very much.

One oddity with these is that they don't have proper mounting yokes but instead mount from the side. This means you have to buy their special lightstand with the stud coming out sideways. This can and will confuse people not accustomed to them. Also they have no slot for dropping in scrims.

With Alzo Digital brand, the 10' lightstands are quite good, the 8' lightstands are almost useless as the base is too narrow, and the stand itself quite spindly.

Tip McPartland

Richard Andrewski July 19th, 2007 04:14 AM

Don't you hate it when someone says "give me a coke" and they really mean "give me any soda of whatever kind"? I never do that. I also hate it when people refer to generic fluorescent fixtures as "kinos" too. While we won't stop people from calling an "HMI" fixture an "HMI" it's still interesting to debunk some of the myths behind all this stuff. Osram certainly doesn't care--it's all great marketing for them either way!

Yes, many products are called "HMI's" but it's really not correct. HMI is a trademark of Osram and is not a proprietary technology or a type of fixture--its just an HID quartz metal halide bulb of very high quality and color rendering capability (but not CRI 95). The bulbs inside might be HMI brand or they might be Phillips or GE but the fixture itself is never an "HMI", its an HID fixture. The main difference between an HID fixture and a tungsten one is a more beefy HID voltage rated socket and a ballast between the bulb and mains which tungsten doesn't need. A UV protection lens helps a lot too. I wonder if that Alzo fixture is really UV protected?

In fact, there are a number of different brands of bulb that all follow the same quartz HID standard that the HMI bulbs set. Phillips, GE, Sylvania, Eiko, Ushio and tons of others all make double and single ended bulbs that are relatively close to each other in operation and type. But calling that "Alzo 800" unit an "HMI" is really pushing it and in particular calling it an "800" is too.

If they mean equivalent of an 800w bulb I'd love to know what technology they have in their bulb because the normal lumens per watt (LPW) for that type is around 70 to 85 with HMI pretty solidly at 85. A couple of advanced Osram 150w G12 ceramic models like the 4ArXS HCD 150W come in at 100 LPW but few elliptical E26 edison MH bulbs come close to that. Alzo doesn't even directly state the real wattage of the bulb they use, they just talk about power draw of 140w. There are no 140w HID elliptical bulbs so it must be a 150w. Why can't they just tell us the bulb? Are they worried we might go to an Aquarium store and buy the same thing for half the price? However, let's try some calculations to see what they were thinking about "800"...

To start, lets figure out the lumens in an 800 watt tungsten at the max of 20 LPW--thats 16,000 lumens. So they're claiming 16,000 lumens out of that bulb. Let's forget for the moment that no 150w HID bulb I've seen puts out that much light.

Next, let's take 16000 and divide by 150 which seems to be the actual wattage of the Alzo bulb and we get 106 LPW. Wow, not even Osram HMI or HCD obtains that efficiency. So it would seem that Alzo is not completely truthful in their claims after all or they've found a new miracle bulb that only they are selling.

Getting more realistic, at best, a 150w HID elliptical bulb like the Alzo one really puts out more equivalent to a 400 to 650w bulb (depending on quality) so it really should have been called the Alzo 600 to be more accurate.

By the way, it's not true that Osram HMI is 5600K. I've done quite a bit of research on all this for my coming products and written some articles about HMI and the technology behind it in a 4 part series in my blog. Teaching people how to build a metal halide fresnel for under $500 which is far better than the Alzo floodlight:

http://www.coollights.biz/wordpress/...egory/articles

Actually, Osram HMI, for the most part falls in the 6000K color temperature and CRI is not 95. So many people using these things everyday thinking they are 5600K when they are really 6000K. Just goes to show that a difference of 400K in that region of daylight isn't very discernible otherwise there would be more talk about this.

Here's the Osram marketing page on HMI:

http://www.osram.com/osram_com/Profe...HSR/index.html

In more detail, take the HMI 575 SEL HR for instance for CRI and color figures:

http://www.osram.com/_global/pdf/osr...mi575WSELe.pdf

And Phillips and GE also make most of their stuff in the 6000K range too to emulate the HMI line. It's not until you get to companies like Sylvania (and Sylvania oddly markets Osram HMI in the states and a more correct version outside like in China), Eiko and Ushio that they actually do it the right way and make bulbs in the 5600K range:

http://www.sylvania-lamps.com/catalo...x.php?id=12670

http://www.ushio.com/products/entertainment/mh-usr.htm

http://www.eiko-ltd.com/Products.asp...x=ESR575-SE-HR

CRI is 90 on average for all these products which is still very good but mostly not 95. And many other models actually come in the 80 to 90 range. Some even fall in the 70 and lower range for "architectural" outdoor lighting or disco lighting use.

Many times, the same fixture companies that are busy calling their fixtures "HMI's" rather than "metal halide" or "HID" or some appropriate generic term are also busy embellishing on claims of CRI too. So its not surprising if fixture or rental company is out there claiming their "HMI" is 95 CRI.

I talked in more detail about a lot of these types of bulbs and their equivalents in my latest article.

http://www.coollights.biz/wordpress/archives/41

If you want something like that but more usable and don't mind DIY, you'd do far better with something like the Lumenlab solution I mention in my articles and an old, used fresnel from eBay.

Jacques Mersereau July 19th, 2007 07:13 AM

Wow, cool info Rich. It appears you have done a lot of work
learning about HMI and other fixtures that output "daylight"
color temp.

My question for you is, if you were going to buy HMI or lights to
be used outdoors what would you purchase or make, while
trying to keep expenses low and value high?

Bob Grant July 19th, 2007 08:19 AM

The term HMI is only used by Osram for some of their HID lamps. The HMI lamps have a shorter arc and more exact CT specifically for film use. They also have a short life compared to their general purpose HID lamps which carry a unique designation to define the lamp design.

But getting back to the light in question.

Check carefully, it almost certainly is fan cooled. If so the fan noise may or may not be a problem for you.

Richard Andrewski July 19th, 2007 11:48 AM

Quote:

Originally Posted by Jacques Mersereau (Post 714163)
Wow, cool info Rich. It appears you have done a lot of work
learning about HMI and other fixtures that output "daylight"
color temp.

My question for you is, if you were going to buy HMI or lights to
be used outdoors what would you purchase or make, while
trying to keep expenses low and value high?

Good question! Well until someone like me actually comes out with a lower cost version, DIY or the used market is the best solution for the moment unless you want to spend several thousand. A better question is why did it take so long for someone to try to do something about it.

We would already have the stuff out if it wasn't for some unforeseen issues which you always have with product development and also the fact that factory capacity in China is at record highs therefore difficult to get some of what you need right now.

If you read part II of my articles, that's where I actually talk about converting a fresnel to a metal halide counterpart if you decide to go the DIY route.

What I'll be coming out with in the fall sometime will basically be a 150w fresnel based on HQI/HCI type technology and a 575w based on HMI type hot restrike. Prices will be vey good. We'll also should have about 2 models of 575w HMI par--one hot restrike, the other non-hot restrike. A 1200w HMI par to follow at some point in the future when we can get the electronic ballast issues sorted out.

Craig Chartier July 19th, 2007 05:19 PM

Simply put, you need to buy from a company that also will service the fixture. We own twice as many ballasts as we do heads because half of our inventory is always in need of repair. Heat and humidity are the killers for these type of fixtures. Go with Mole Arri or K 5600 for smaller fixtures that you will be happy with for along time. Yes it will cost you more, but it will last twice or three times as long before you will need service.

Jacques Mersereau July 20th, 2007 06:50 AM

Have you seen Kobold?
http://www.bron-kobold-usa.com/
At NAB they had one of their lights and ballast set up under a shower
of rain kept both wet. That was pretty impressive.
The other nice thing was that
their housing is so well designed that they can be handled
even after being left on for a long time not in the rain.

BTW, they cost about the same as other HMIs.

Richard Andrewski July 20th, 2007 07:35 AM

The ability to rainproof fixtures has been something around for a long time in the metal halide floodlight market. Lots of those fixtures running year round outside. It was just a question of transferring that "IP" type rating to stage/studio lighting which shouldn't be that big of a deal.

Mark Sasahara July 20th, 2007 11:23 PM

If I'm not mistaken, the Kobold Bron fixtures are more water resistant than most HMI's. That's one of their selling points. Pretty sure that you can't get any other lights as wet without some fireworks occurring.

They're popular with News and ENG folks. I'd love to get some for my kit.

Paul Cascio July 25th, 2007 09:05 AM

Does Osram call thier bulbs "HMI Brand, ...lights"? If no, HMI can become part of the lexicon and they lose thier trademark protection. I'm sure they know that but figure the money they'll make in the mean time will more than offset it.

Is HMI an acronym for a descriptive term?

Richard Andrewski July 25th, 2007 05:52 PM

Quote:

Originally Posted by Paul Cascio (Post 718325)
Does Osram call thier bulbs "HMI Brand, ...lights"? If no, HMI can become part of the lexicon and they lose thier trademark protection. I'm sure they know that but figure the money they'll make in the mean time will more than offset it.

Is HMI an acronym for a descriptive term?

HMI is a acronym for "Hydrargyrum Medium-Arc Iodide” Hydrargyrum is the latin for “mercury". It is a registered trademark of Osram and as far as I know they call them HMI brand.

Ralph McCloud July 26th, 2007 06:39 AM

Quote:

Originally Posted by Tip McPartland (Post 713768)
These aren't exactly HMI, which is a trademarked term for a particular design of HID. These are very close, however and are HID which are arc lights with very similar characteristics. The color temperature is lower at 5300K vs. 5600K for HMI. Also the color rendition index is down at around 85 versus 95 for HMI. All that having been said, I have two of them (Alzo Digital brand) and like them very much.

One oddity with these is that they don't have proper mounting yokes but instead mount from the side. This means you have to buy their special lightstand with the stud coming out sideways. This can and will confuse people not accustomed to them. Also they have no slot for dropping in scrims.

With Alzo Digital brand, the 10' lightstands are quite good, the 8' lightstands are almost useless as the base is too narrow, and the stand itself quite spindly.

Tip McPartland


Are you using your lights to light talent or are you capable of lighting a room with them without the outside being blown out (do you understand?) Can they give off enough light to accomplish this?


I'm trying to light interiors (where there is a lot of outside light coming in) and I also want to be able to capture the outside as well. I am able to do this with "regular" HMI type lights (1.2Ks with ballast, etc.) But I'm looking for a cheaper alternative.

Thanks for any advice. Ralph

Tip McPartland July 26th, 2007 12:05 PM

Alzo HID Brightness...
 
You would need hugely powerful HMIs to compete with direct sunlight, but these work fine with light spilling in through windows and so forth. I'd frame the windows out or cover them with ND plastic.

Tip

Ralph McCloud July 26th, 2007 04:31 PM

saw some "HMI-type" lights today. Review . . .
 
I borrowed a friend's Wescott Spiderlites today. http://www.fjwestcott.com/fjw.com/products/td5.htm

I was hoping to find a cheap alternative to HMI lights to light rooms. These lights are not the answer. They might be useful in lighting talent (if they are placed really close to the talent) But they aren't even remotely powerful enough to light a room with 5600K light and see the outside.


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