DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Photon Management (https://www.dvinfo.net/forum/photon-management/)
-   -   LED test for DIY ring light (https://www.dvinfo.net/forum/photon-management/471346-led-test-diy-ring-light.html)

John Saunders January 20th, 2010 10:32 AM

LED test for DIY ring light
 
So I am thinking about making a large led ring light since they are so expensive to buy. The litepanels cinema one is like $8000 and the mini is $2300. Now I know I will not get the same performance as the cinema (it's a nice light) but I think I can match or do a little better than the mini. I plan to have about 120 broken up into x6 20 led rings. I wouldn't dim them because I am worried about flicker even with PWM so I plan on turning the rings on one at a time for some brightness control. I am planning on spending $300-500 for the leds, cuircut boards, custom metal enclosure and the like.

My first step was to try and pick between the 4 leds I found that I thought would work the best. All of them are about $0.98 each and were rated for about the same output. I set them up one at a time 6 inches away from a color chart and a few colored markers (wanted to see how they rendered the colors). They were all powered at 3.5 VDC that I brought down from a 6VDC 180ma power supply with an adjustable voltage regulator. I then took a picture of each one with a 85mm 1.8 canon lens at 10th of a sec. One picture with the daylight WB setting (I think its 5200k even though the chart I was holding says 5600k) and then another picture with the kelvins set to what the led spec sheet rated them at.

***If you want to download the images they are here Ledtest

All of the pictures:
http://cgllc.com/ledtest/ledtestcomblowres.jpg

What I think are the 2 best (the kingbrights):
http://cgllc.com/ledtest/Kingbrightcomp.jpg

at 100%:
http://cgllc.com/ledtest/Kingbrightcompclose.jpg

Comparing the White, Black, and 50% Grey from Photoshop:
http://cgllc.com/ledtest/Kingbrightcompclosebwg.jpg

So I think I like the 6000K the best but it will need more of an orange gel to use it with other tungsten lights.

Please let me know what you thoughts are and if I should have done the test differently. Thanks.

Giroud Francois January 20th, 2010 11:38 AM

http://www.giroud2.com/download/ring.jpg
http://www.giroud2.com/download/ring1.jpg
http://www.giroud2.com/download/ring2.jpg
http://www.giroud2.com/download/ring3.jpg
http://www.giroud2.com/download/ring4.jpg

cost=60$

John Saunders January 20th, 2010 10:41 PM

That's cool what led did you use? I'm looking to do something a little bit bigger.

In between this:
Litepanels Ringlite Mini

and this:
Litepanels Ringlite Cinema

Giroud Francois January 21st, 2010 03:19 AM

well if i would need so much light, i would not go with led, it is too expensive.
I use my ring light for subject very close from the camera ( 6 feet or less), so in event
i can do a quick interview or gor between people without disturbing and still get correct lighting (and it fits my bag and does not sucks tons of battery)
if you want more surface , i would use led arrays (seame led i used but on a small printed circuit).

http://www.giroud2.com/download/ledring.xls

try DA SH Plastic Mold they are very nice chinese guys, cheap and good products.
they now produce their own leds, but the one i got have very nice cold and warm white.

Giroud Francois January 21st, 2010 03:22 AM

by sticking together some of these modules
DA SH Plastic Mold

you can probably build a big ring for cheap and almost no work.


All times are GMT -6. The time now is 09:01 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network