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Old January 11th, 2009, 03:07 AM   #136
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Hi Richard...

Any comparisons between the color quality of your light and the one marketed by FloLights?

The FloLights require a minus green filter to attain a better match to daylight.

Nice work on the light design/manufacturing.
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Old January 11th, 2009, 07:44 AM   #137
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Hey, Richard

Does the A/B plate include a power tap connection, to maybe power two lights off the same battery?
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Old January 11th, 2009, 06:11 PM   #138
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Dean,

Thanks for the kind words! If you want to use the fixtures by themselves, with custom white balance on digital mediums, minus green isn't necessary. It's mainly necessary when mixing them with full spectrum sources like HMI, CDM, fluorescent, real daylight or real tungsten. At this point, you should count on 1/8 minus green for just about any of these type of LED fixtures that use the lower cost 5mm round daylight LEDs. Using RGB LEDs or other similar "mixing" tricks in other fixtures we will be able to obtain a better LED product that can mix well with other light sources.

Brian,

On the battery plates, yes there is a D Tap and I would think that should work although I didn't think of it as a test. If I get a moment, I'll pick up a D to D cable and try it.

Dan,

Thanks! A lot of hard work went into this.
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Old January 11th, 2009, 08:51 PM   #139
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Richard, I'm looking to replace my existing two Lowel hot light setup (Totalight in 24x36 Photoflex video softbox box and iLite in 12x16 Photoflex box) with equiv type LED's - this item looks like it will meet my needs to replace my Lowel Totalite - what's the equiv light output in relation to a totalite? I use it primarily in my Photoflex video softbox for doing interviews and wondered what the light quality was in relation to my 24x36 box - I currently have to back it off because of the amount of heat the thing generates and I would like to have the light be daylight balanced and cool to work with in tighter shooting situations.

I need a two light kit that is compact since all my shooting is on location (and eventually to remote locations) and I'm not totally sold on the LightPanels - especially since they are so expensive in relation to this product. I would match your product with a lightpanels micro as a hair light and double duty on camera light for my two light kit.

If this meets my needs, February won't get here soon enough
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Old January 11th, 2009, 10:31 PM   #140
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I'll probably be the last person to say that LEDs are superior to fluorescent or HMI/CDM lighting--at this time. There will always be tiers of products and no one product will serve well for all uses.

You have to remember, we are in a very early stage now with LEDs--especially the smaller 5mm ones like this. Think where fluorescent was 10 years ago and you have the picture with LEDs. Fluorescent manufacturers didn't care about CRI back then. It was much harder to find a usable fluorescent tube for video/film at that time. Fluorescent was for early adopters back then. Today its so much more advanced and getting more and more common to find a good tube with good color temperature and color rendering. LEDs are now for early adopters and those that need something compact, solid state and with a high leverage for power input vs. light output--which if you consider them from a LUX / footcandle output to watts consumed, they beat all other lighting. And, DC operation is easy with them. I see them, as I have said many times, as a specialty fixture for use in those situations where batteries/low voltage DC power would help out a lot because of lack of normal power mains.

That being said, these fixtures will work fine as an equivalent to a 650w fresnel (wherever you might use that) and wherever you can control the other light in the room (windows, practicals, etc.). Just remember, LEDs like these work well by themselves or mixed with similar ones to themselves but aren't great for mixing with other tungsten, real daylight, flourescent or HMI. So, view them like that and you will have a great portable source that can work off batteries when necessary. Your tota mixes well with other light, including daylight if you gel them, because they use tungsten and that's a full spectrum source. A good fluorescent or HMI will do the same. Another issue is that the output is very hard compared to your diffused softbox tota. Adding diffusion to the LEDs will weaken them. I would think that the best thing to use for diffusing somewhat would be a cracked ice or prismatic plastic panel like used on some ceiling or fluorescent fixtures, but it will be harder to get that big surface emanating light like a 24 x 36 softbox and be as strong. LEDs can have a very strong output but they can be weakened quickly by something like a silk.

If you're not needing to work off batteries or super portable isn't of the greatest necessity, I'll still recommend a fluorescent or CDM/HMI any time for energy efficient soft or hard light, great color rendering and ability to mix with other fixtures well. Plus you can't beat the cost effectiveness of fluorescent and CDM for shear output and cost per lumen too.
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Old January 12th, 2009, 12:19 AM   #141
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Richard - the needs I have for shooting with a light source entails having portability as a paramount feature - hence the reason for asking about this light as a primary source - The softboxes are secondary - I can use diffusion scrims if needed and have in the past, but I need a soft light source that can be used either off a DC or AC power source. I figure with one of these lights along with a smaller light for hair/rim/background, this compact kit will travel well and meets the needs of how I shoot as a self contained video shooter (solo video journalist).
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Old January 12th, 2009, 12:22 AM   #142
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Fluos do just fine as soft lights, so there may not be much need to soften LED lights...

However, I'd very much like to find a cool (as opposite to boiling-hot tungsten) hard light source like fresnel, hopefully in LED version.

Equivalent of 650W-1K Lowel DP light without all the heat would be cool. OK, bad pun :)

Anything like that on the horizon?..

PS - just read Cliff's post above, and it seems like Richard is being torn in two different directions here :)
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Old January 12th, 2009, 02:27 AM   #143
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Alex,

HMI lights don't have infrared in their beam, so while the fixture itself gets hot, the light from an HMI doesn't heat up the talent. So, that horizon you seek is technically here already. Cool lights' 150w HMI fresnel produces the equivalent light of a 650w arri tungsten with a daylight gel, only draws 150w and isn't hot for the talent.

Oh, and it doesnt cost much more than the arri fixture either. pretty crazy.
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Old January 12th, 2009, 06:48 AM   #144
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Alex and I have talked about the 150 cdm before and I think he would prefer LEDs. Many think the CDM 150 is a great size but Alex thought it was too big for his needs. You just won't get much smaller than that I'm afraid to get anything useful and that can do everything a fresnel can do. Focusing, wide beam, narrow beam, projection, hard shadows--it's hard to beat that form factor. There just is no such thing as a single point source LED fresnel at this point and I don't think there will be for a long time. We have looked at a 100w LED but the problem is that it would require a huge and heavy heat sink to keep it alive. There goes portability and weight. Its okay for street lights because you can hang the heavy heat sink on it and they can cost justify the extra cost of the LED too. Thus, if we tried to use that, the form factor of the fresnel would be totally different to make the wide/narrow beam functionality. It would be too expensive, too heavy and not what you want (at this point).

Put an array of LEDs together and you approximate some of what you're looking for but there are multiple shadow issues so you can't use it everywhere you would normally use the single point light source fresnel (tungsten or HMI/CDM). Like for "cookies" for instance or when you need a hard shadow across something. LED arrays won't do that.

We're not really torn, its just realism and that each of these tools still has its place in the arsenal: flo's and hmi are far from dead. I know its not what many want to hear but its just too early--we have some more advancements to go before its what you really want to replace everything.

When designing fixtures you have to know what people are expecting in each form factor and when people say the want a "fresnel" there are certain behaviors they expect from that. Hard shadows, projection, wide or narrow beam, etc. The single point light source of an HMI/CDM or tungsten bulb is all that we have that can do that well and cost effectively right now. If you can settle for an array of LEDs for just general lighting of a subject, and you can control the other lighting in the environment (or add gels where necessary to adjust the fixtures) then the LED fixture will be just fine.
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Old January 12th, 2009, 06:55 AM   #145
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Quote:
Originally Posted by Cliff Etzel View Post
Richard - the needs I have for shooting with a light source entails having portability as a paramount feature - hence the reason for asking about this light as a primary source - The softboxes are secondary - I can use diffusion scrims if needed and have in the past, but I need a soft light source that can be used either off a DC or AC power source. I figure with one of these lights along with a smaller light for hair/rim/background, this compact kit will travel well and meets the needs of how I shoot as a self contained video shooter (solo video journalist).
My thinking pretty much too. We made this for the person that travels a lot and can shoot in controlled circumstances. The flood panel will be great for that. We have a spot panel too, but ultimately for guys like you or Dan Brockett, you'll want an even smaller spot than this panel for use as hair / rim / back light and keeping things small, minimalistic and super portable. Something with maybe 150 LEDs or less in as small a package as possible. That's one of our next products because we hear this story a lot and we know what people are looking for. Can you use our 600 LED spot panel as a hair / back / rim light? Of course, but its a bit of overkill though and you'll find yourself reaching for the dimmer a lot. I ran some tests with that and it's large but still small enough it can be positioned behind someone's head and obscured for the rim effect. It can also, of course be placed up on a stand behind the person for the hair light. You can put it on the floor and shine it up against the wall for a beam effect as well, although I think a fresnel still excels the best for that effect.

Anyway, all these instances are where the smaller 150 or less LED spot would come in really handy. Or we could do it with 3 or 4 1w LEDs--that's certainly another way to go as well.
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Old January 12th, 2009, 06:13 PM   #146
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Given the nature of the kind of work I produce, and working self contained, this light appears on paper to really be ideal for my needs (could have used it yesterday on a shoot) - specifically for the head and shoulders type interviews typically done.
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Old January 18th, 2009, 03:43 PM   #147
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led lights

Hi
I had tested this led light and i thing it is very good (The one with 60 degree head) Camlight
*keep shooting*
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Old January 20th, 2009, 12:29 AM   #148
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Some Impressions Of The New Coollights LED 600s

Hi all:

I received the LED 600 lights air freight from Richard in China last week. Both lights came packaged nicely. The nylon bags that the lights come in are very nice, black ballistic nylon with a white Coolights logo silk screened onto the front with an adjustment strap. The bag also features plenty of room to house the power supply for the lights.
http://www.dvinfo.net/conf/attachmen...1&d=1232432579

A very nice lanyard with a aluminum caribiner clip is attached to the lights so that the power supply can be hung from your light stand. This adds the benefit of better air circulation around the power supply. As we all know, less heat equals longer life in electronics. Since I am in the U.S., the power supply came equipped with a detachable 12' standard grounded threee prong OSHA cord. The cord is heavy duty and not cheaply made. Not sure what the AC cord supplied for 240 V countries will be like. The power supply itself is variable voltage so it will be the same for all LED 600s the world over. The power supply terminates in a four pin DC XLR cable.
http://www.dvinfo.net/conf/attachmen...8&d=1232432576

The rear of the light panel contains a larger master power switch flanked with five bank power switches. This allows you to vary the output of the instrument without dimming. Dimming in LED fixtures does cause a shift in color temperature in the output, although this varies from instrument to instrument. The light also features a nice rotary dimmer underneath the fixture near the light stand adapter. I like that the dimmer knob is fairly long, it makes it easier to find in the dark or when you are not looking underneath the instrument for it to adjust it. The dimming effect is nice and linear, no major jumps in the dimming percentage. I do not own a color meter so I was not able to measure the color temperature shift as the instrument was dimmed, but I assume that there is some shift.
http://www.dvinfo.net/conf/attachmen...1&d=1232432646

The light will fit into the main compartment of the bag with the included barn doors in place. The barndoors are very nicely done and extend to about 8" on all sides. Since the instrument is square, it seems as if all four barndoors are the same length. This makes folding the doors up easy and quick since you don't have to search for which set of doors are the horizontal and which are the vertical as you would on most lights. Richard has discussed the possibility that he may supply various accessories for these lights in the future that could include color correction panels, diffusion panels and possibly a speed ring for softboxes. The channels that hold the barndoors and would be used to hold these opther accessories are very heavy duty and could easily hold additional weight and width besides the barndoors. The clips that hold the barndoors to the light are spring loaded and heavy duty, much as you would get on an Arri or other professional instrument.
http://www.dvinfo.net/conf/attachmen...1&d=1232432646

The front of the instrument features six hundred 5mm LED lights, arranged in a square. The LEDs are bare, there is no safety glass or protective panel in front of them, although with the barndoors folded over the light, the LEDs are protected during transport.
http://www.dvinfo.net/conf/attachmen...1&d=1232432646

The light stand adapter includes a standard 5/8" receiver that will easily allow the light to be mounted on a standard light stand or C-stand arm. Adapters are available from third party sources to adapt this standard 5/8" receiver to other configurations like junior and senior pins, 5/8" recepticles, etc. The tie down knob is plastic but seems to be large enough to crank down on safely and the light stand adapter feels as if it would hold the additional weight and leverage of a small Chimera or other softbox fairly well without sagging or drooping the light fixture down.
http://www.dvinfo.net/conf/attachmen...1&d=1232432646

I received two LED 600 panels, a 5600k flood panel and a 5600k spot panel. I was interested to see the difference in output between the two so I set them up for some informal testing. I took light measurements and readings with both my Panasonic HPX170 and with my Sekonic L308s light meter. The readings were taken in an otherwise dark room with no ambient or other light. I recorded the following exposure readings in each situation.

These are real world numbers, not laboratory measurements of the lights since I do not have all of the necessary equipment to set up and measure from a truly controlled situation.

I recorded the following exposures. I was impressed with the output levels.

Camera exposure
Camera - Panasonic HPX170 P2 camcorder
ISO: I rated the HPX170 at ISO 500 at 24 fps with a 180d shutter. The readings were taken from the subject position with the Sekonic L308s light meter at exactly 6' from the LEDs to the subject, female with white skin. Besides the light meter reading, I also let the camera meter the subject, I used the camera's zebras set at 75% and 100%. I adjusted the camera to record the highlight areas of the face with a decent amount of peaking at 75% and highlights anywhere near 100% exposure. The readings from the HPX170 and the Sekonic L308s were identical. I metered each light individually and recorded the following exposures.

5600k Flood Panel direct at meter/subject
24fps @ 180d @ 6' = f 4.08

5600k Spot Panel direct at meter/subject
24fps @ 180d @ 6' = f 5.65


I then proceeded to take a different set of measurements to check the actual FC/lux output. Since my light meter does not have FC or lux readouts, I had to do some calculations. I am not sure if these measurements are exact as the EV/FC and lux scales are logarithmic and not linear. Standardized FC measurements are always taken at ISO 100. I recorded the following measurements. Note that these readings were take at a distance of 5', not at 6' as the above camera exposures were.

Flood Panel
EV 8.5 @ 5' = 900 lux = 83.6 FC

Spot Panel
EV 9.5 @ 5' = 1800 lux = 167.2 FC

By this measurement, something seems off. The spot panel does seem a lot brighter than the flood panel but not twice the FC. My calculations may be off here as I am using an EV to lux calculator. In the measurements above, the EV reading is definitely accurate but my calculations in converting to lux and or FC may be off so if you are a stats whiz, please feel free to run these numbers and see if your results vary from mine.

Color Cast
As expected, the LED600 panels do exhibit a small green spike in the color output. Evidentally this is endemic to 5mm LEDs and I can tell you from experience that the LED500 Prompter People panels also exhibit the same green spike.

The stills below were taken with the setup shown below with the spot panel punched through the small Chimera as a key source and the flood panel bounced off of a 42" white flexfill. LED lights have a harder light quality than fluorescents so I would typically not use them without diffusion or bounce. I was concerned that the LED 600s might not have enough output to use as a bounced instrument or for use through a softbox but they surprised me. They worked quite well, both through the Chimera and bounced off of a Flexfill. The samples below are lit only by the two LED Panels, the only ambient light in the room was an incandescent practical shining on the wall (the orange looking wash on the picture) and some twinkle lights on the potted plant. Both practical sources were located about 18' behind the subject so they did not affect the color cast on the subject at all. There was no hairlight or rim light used to separate the subject from the dark BG.
(this still was shot during the day but the test shots below were shot with the same setup at night

The first image was shot at 5600k wb preset on the camera.
http://www.dvinfo.net/conf/attachmen...1&d=1232432646

The second image shows the same image after color correction in FCP's three way color corrector using the grayscale chart the subject is holding.
http://www.dvinfo.net/conf/attachmen...1&d=1232432646

I am going to shoot some images using manual WB, which I suspect will work almost as well as FCP's three way color corrector. You can see that under the 5600k preset on the camera, the lights do have a definite green spike although it was quite easy to correct with the color corrector in FCP. Another alternative would be to mount some -1/8 green gel in front of the lights while shooting. There are three easy and effective solutions to mitigating the slight green spike in the LED600s.

I am continuing to shoot tests with the LED 600s and will keep posting as I discover more and more. Please feel free to PM me or post in this thread if you have specific questions about the lights. Now that I have done some testing, my next challenge will be setting up a decent looking shot using the LED 600s along with possibly some tungsten and or fluorescent instruments. As long as the LED 600s are being used solely to light the subject, I do not foresee problems is adding other color temperature instruments as background and accent lights.

I will be posting a lot more as I explore these lights. I did not order the battery plate that Coollights has available but I am toying with the idea of buying a lower cost battery belt to see what sorts of run times can be achieved in using these lights on location using battery power. More on that later.

Dan
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Old January 20th, 2009, 08:52 AM   #149
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Dan,

I've received my Coollights now too, they are pretty impressive. I took the battery plate option though. One quick question, what softbox are you using on the one in your picture? and how did you attach it?

Dan
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Old January 20th, 2009, 09:19 AM   #150
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Hi Dan:

That is a small Chimera Quartz bank (24" x 36"). It is actually not attached to the LED 600, it is being held in front of it on a separate C-stand. I have been speaking with Richard how users will want an integrated or add-on speed ring for softboxes for these lights so hopefully one will be forthcoming. In the meantime, I may create one for myself.

I already looked through the existing 250 models of Chimera speed rings on the market and none look as though they will fit the 9.75" wide channel on the LED 600 so at this point, I may have to fabricate my own or go to a metal shop and have it done. I am sure that Richard can have them made much more efficiently in China though. Really all that needs to be done is to take the barndoor frame, remove the door panels and weld on four socket receivers for the Chimera rods. Piece of cake.

Best,

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