Video / wide light based on LED emitter "cake"?

OS74

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Feb 10, 2009
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Hi all!

What are the pros and cons of using a composite emitter for a general wide light for video and photo background lightning?

For example DX has heaps of variants from 10 -100W. I was thinking about just making an aluminium puck with a recess for the emitter and an O-ring grove and a acrylic lid on top.

Many of these are quite high voltage with 10 led in series. Also I don't know if the quality of light is too poor("white" enough). There are also variants with fewer discrete emitters such as XMLs.

Thoughts?

Cheers
/O

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I would say that are OK for DIY at basic step , but in general their quality vary fluctuates a lot . That mean Vf for single led , soldering quality , color ...

https://www.youtube.com/watch?v=UoxexFBmr0E&feature=youtu.be&t=3m48s

I think these leds in massive sale such as DX are not selected in the peak of Gauss bell but in +/- 2 or even +/- 3 sigma if you know what that mean and also price between 2 and 3 vary.

Same process is (was ) with AMD processors ( that is very actuall at high end graphic cards ) probably with Intel too they are made with for example with 8 cores if same is bad they disconnect one core and you have

operating 6 core processor or you have more or less memory or memory bandwidth..... They work for what they are presented but with lower performance and at lower money scale.

Still is there more profit if you sell something not so perfect for less money on an ''undemanding market '', then you put product ( including production costs ) direct in to the bin .

But look good leds have also on DX price
 
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OS74

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True, you would have to expect random quality.

What is a good source otherwise for big high power video emitters?

What are the candiate viddeo emitters anyway? For example looking at a random selected commercial light light-for-me red star. It is using a compact 200W emitter that looks nice, but it is nowhere stated who the manufacturer is.

Cheers
 

OS74

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Right,

What is your experience of these COB, used any? I am thinking that it would be good to use units with a Vf close(-ish) to the battery U around 12V. Many COB in the high power range seem to be 36V or twice that.

/O
 

DIWdiver

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Without having used any of these devices, I would guess that Bridgelux and Cree are the big, dependable names and that anyone else is an off-brand. You'll pay accordingly.
 
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I am thinking that it would be good to use units with a Vf close(-ish) to the battery U around 12V. Many COB in the high power range seem to be 36V or twice that.

:oops: basically these led arrays are build for large infrastructure , public or street lighting where is power grid 110V 60Hz AC or 230 V 50Hz AC so there is absolutely no need for 12V DC .

----------------------------------------------

post 2 video https://www.youtube.com/embed/NjKgPLeJ79Q?wmode=opaque
 
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OS74

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Feb 10, 2009
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Interesting video! I've ordered one 100W module. It is going to be interesting to try it like in these videos. As they are so cheap it is likely something dodgy like this going on.
 
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