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-   -   HID Spot (https://www.dvinfo.net/forum/photon-management/88725-hid-spot.html)

Christopher Witz March 12th, 2007 07:11 AM

HID Spot
 
I could not help but to buy an HID rechargeable spot light at samsclub this past weekend.... 6000k temp and really bright! even in broad daylight I see it hitting my barn 100' away!

it appears to only have a 35 watt bulb.... but the par reflector beams it nice!

I can't see any odd color to it on video with my z1.... I've done some research and the info on these HID lamps are varied..... CRI not mentioned on bulb or packageing nor anywhere while google searching the light.

just pointing it up at my ceiling in the family room.... it brought the light level up with daylight shing thru the windows.....

might be nice as a spot to go with kino style soft lights.

battery last 70 mins.

The only downside so far is that it will not operate while "pluged in".... your limited to the batt time. also.... they don't like being turned on and off a lot.... they need to cool down to restart.

$89..... hmmmm. I'm temped to go buy the 8 they had on the shelves......

any thoughts?


also... when on..... there's that tanning bed smell... ya know.... like the burning bacteria! so I'd imaging the uv is high.

Richard Andrewski March 12th, 2007 06:18 PM

Hi,

You probably have a high quality metal halide or ceramic metal halide (CMH) bulb in there. MH can go up to 80CRI, but CMH (HMI which is a tradename of Osram belongs to that family and was one of the first commercially successful ceramic metal halide and is mostly useful to video people because of its "hot restrike" capability and high cri) can go to 95 CRI. HID (High Intensity Discharge) is the larger family that includes not only these but also high pressure sodium vapor and mercury vapor which are barely suitable as street lights let alone for video production. The nice thing about these lights is that, while they are hot compared to fluorescent, they are still more energy efficient than tungsten by at least 3 times. A 150w MH puts out about as much light as a 450w tungsten.

Can you turn your spot back on immediately after turning it off? If not, its either a lesser quality CMH or just a regular MH without hot restrike. You usually have to wait about 5 to 10 minutes for those bulbs to settle before they can be turned back on.

In addition, they're great in spotlights, pars and fresnels because they are a hard or point light source and that's what those instruments work with. Fluorescent because of its nature is always soft and is a great, cool and energy efficient softbox/softlight substitute. Your spotlight can work well as a video lighting instrument as long as the CRI is 80 or above. From what you said, it sounds like you got a good one.

Marcus Marchesseault March 12th, 2007 11:01 PM

I have seen Metal Halide lamps with CRI as high as 96. High CRI is not common and the lamps sometimes only work in certain positions (horizontal or vertical). I'm confident there will be an affordable alternative for high CRI lighting that outputs 5500Kelvin with less wasted electricity. HMI is still so expensive that it isn't practical for many people.

Richard Andrewski March 13th, 2007 12:20 AM

If they're that high in CRI they are probably CMH, not just MH. A lot of people just call a CMH a metal halide. See what I mean? There's just so much confusion on this subject that it only helps contribute to products staying high in price.

As for affordability, I think this is going to change pretty soon.

Christopher Witz March 14th, 2007 10:44 AM

I just shot a quick test with the z1....

please don't comment on my guitar playing.... and yes, the strings are old.

F4, 0 gain, 1/6oth sec, daylight CB, ND 1, nothing done in post. ( looks a little cool on the quicktime... looks great on my projector thru appletv.

The test is to show the exposure outside ( high noon today ) the window as well....

spot was bare, and 22 feet away.... foamcore fill card to my right. no other lights on in the room.

http://www.witzke-studio.com/hd/hidtest.mov

Christopher Witz March 14th, 2007 11:10 AM

here's a tighter shot..... brought the light in to 10' and brought the fill card around front a little..... I'm happy for $90! ( needs to be warmed up a tad though.... maybe a 1/4 basturd, or just 3way in post )


http://www.witzke-studio.com/hd/hidtest2.mov

Richard Andrewski March 14th, 2007 04:33 PM

Wow. Looks great and a good find there. What camera are you using--HVX? I'm writing an article on this very subject right now on my website blog. More people need to know about what HMI really is and that there are other choices that are quite a bit less expensive.

Christopher Witz March 14th, 2007 05:48 PM

shot with z1u

So far I'm plesently surprized with the results.... I only wish it would also run plugged into the wall...... it will run off another 12v source if it's at least 3.3amps.

rumor has it... these lights can be boaght for $50 at sams clubs online auction.

hmmm.

Richard Andrewski March 14th, 2007 08:46 PM

Quote:

Originally Posted by Christopher Witzke (Post 641792)
shot with z1u

So far I'm plesently surprized with the results.... I only wish it would also run plugged into the wall...... it will run off another 12v source if it's at least 3.3amps.

rumor has it... these lights can be boaght for $50 at sams clubs online auction.

hmmm.

$50? Amazing. They must have bought them from someone who wasn't successful at marketing them. That's an obscene price. The ballast and bulb alone are worth that in pure cost. I would also say based on what I see in your video that they are at least 80 CRI and giving no green cast at all.

Christopher Witz March 14th, 2007 09:44 PM

When reading in cine trade mags.... I've offen notice the mention of a 5CC of magenta added to the lens of the HD shot features .... i.e vipers and f950's

Any chance this helps with uv? or green spike with HMI's? I try not to put anything but air or a PL in front of my lens..... so would a little CC of megenta in post do the same thing?

also... the housing of this spotlight is a buzz kill..... I mean, I can clamp and angle it on a stand..... but, it looks like I'm going camping after the shoot!

hey.... maybe I could cook smores with UV?

Richard Andrewski March 15th, 2007 12:01 AM

Well I hope that the front of the spotlight has some uv protection glass on it. Usually they do. As for outer appearances, for $50 I guess looks don't count so much.

As for magenta filter, I wouldn't add it to the lens personally. Just gel the light with minus green (which is magenta) if it seems to be a problem but I don't see a problem there, do you? I'm researching this subject quite a bit now and I haven't found one CMH bulb yet that gives a really noticeable green spike but then I'm only ordering stuff 80 CRI and above and the green spike is mostly a problem with low cri bulbs and film. Digital mediums are really forgiving.

I don't shoot any kind of film anymore so its really not an issue for me.

Steve Roark March 15th, 2007 12:20 PM

Quote:

Originally Posted by Christopher Witzke
shot with z1u
rumor has it... these lights can be boaght for $50 at sams clubs online auction.

Actually, it was $54 (plus tax & shipping). :)
I'm always a sucker for diy lighting...

thanks for the tip.

Marcus Marchesseault March 15th, 2007 07:21 PM

Link for the light?

Your videos look convincing.

HID is roughly 4x as efficient as tungsten, so 35Wx4 isn't so bad.

Richard Andrewski March 15th, 2007 07:38 PM

Quote:

Originally Posted by Marcus Marchesseault (Post 642429)
Link for the light?

Your videos look convincing.

HID is roughly 4x as efficient as tungsten, so 35Wx4 isn't so bad.

Actual figures are about 80 to 140 lumens per watt for metal halide or ceramic metal halide for anyone interested.

Marcus Marchesseault March 15th, 2007 07:43 PM

As I recall, studio tungsten is 20 lumens per watt, so what would make HID 4 to 7 times as efficient? That's even better!


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