LED panel comparison: color charts, vectorscopes, light loss

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People ask me all the time, “what LED panels do you recommend?” “What’s the color like on that panel?”and “”Does putting an Airbox Softbox on the light affect the color?”, so I decided to do some testing, as scientifically as possible.  What you’re looking at is footage shot of the DSC labs OneShot chart, where each of the color patches is carefully calibrated to match up to the six points on a vectorscope, as well as four skin tone patches that line up with the “skin tone” line on a scope.  A perfect light source and a perfect camera would land each of the dots right on the vectorscope targets. You can observe which way a light is biased by seeing in which direction the six points tend. Distance from the center indicates saturation.  For example, the top target on a scope is the red reference, and if you see the top point on the star significantly to the left of the target, you know that the light source skews towards yellow. One the source that’s used in this sample chart, you can see how desaturated the green point is, indicating an overall magenta cast.

Here is a sample vectorscope with the targets labeled clearly, if vectorscopes aren’t something you look at often.

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The video below is made from the powerpoint I put together of the results.  A video of stills in a powerpoint of vector scopes and color charts?  That’s some exciting viewing! No, but seriously, it’s data that actually tells you something.   If you want to click back and forth to examine those vectorscopes closely, you can download the powerpoint.

•Tungsten source for a control group
•Litepanels Astra, set daylight
•Litepanels Astra, set tungsten
•Dracast 1000 daylight
•Litepanels D-Flood c. 2007 manufacture
•Flolight Microbeam 512

 

 

I plan to add some budget panels to the testing mix as soon as I’m able so we can see how much difference there really is between the cheaper panels and the pricier ones, but this is what we’ve got for now. Also, when I do more testing, I’ll strive to be more precise with the exposure.

My take on the test results:

1) I’m surprised that the leko doesn’t look better. The skin tone looks good, but on the scope, the yellow still looks a little desaturated and skewed towards red, and the magenta skews towards red as well.  That’s not too surprising since it’s somewhat aged bulb and probably burns a little warmer than it ought. It’s possible that a little glare on the surface of the chart threw things off.

2)The Litepanels D-Flood, the original that people refer to as a “Litepanel”,  still works but is pretty outmoded now.  You can see that it’s two stops less bright than the more modern panels.  The color also is a little iffy on the scopes- pretty much all six colors skew one way or another. It looks liek an overall magenta cast- see how the green point is short(desaturated) and is slid way up towards yellow and red.

3)Astra Daylight- most of the points look pretty close to on, except the green again.  Were they making sure to avoid the famous green cast of LEDs and overcompensated towards magenta? My skin tone looks pretty good though.  I’d happily use that on a shoot. I couldn’t perceive any material difference when I put the Airbox on the light. Interesting was that the Astra set to daylight was almost, but not quite as bright as the single-color Dracast panel. One-color panels are always brighter than their bicolor cousins because all the LEDs are devoted to the one tone, rather than having half of the emitters dedicated to each side of the spectrum.

4)Dracast 1000- This was the brightest panel I tested. Also worth noting is that this panel runs a little warm on a standard color meter, around 5000 K.  White balancing the camera to the source made this not very apparent, but it’s something to know about.  On the scopes the blue and cyan points are pulling towards each other, and the yellow is definitely skewed towards red.  I find the yellow square on the chart a little icky looking. The skin tone? Not bad, looks a little pink to me. However, on the scope, the magenta point seems pretty spot on, it’s just that its complement in green that is off-target.

5)Litepanels Astra, set to tungsten. The scopes seem to be more on-target here than in the other lights, except for that yellow point which is skewing to the orange and the red which is oversaturating a little. For a tungsten LED, it’s quite good.  Those traditionally have been the worst-looking LEDs, but they seem to have gotten it right with this one. The skin tone isn’t perfect, it does bring out the reds a little more than I like.

6)In general, there didn’t seem to be much noticeable color shift when I added the Airbox Softboxes to the lights.  FYI! 15% off all Airbox products, Nov 27-Dec 2, Black Friday-Buy Stuff Monday sale. Airbox Inflatable softboxes are a tool to adjust the quality, not the color, so it’s nice to be able to say that they are neutral in color.

7) The Flolight Microbeam 512-  looks like the exposure was a bit off here, but nonetheless, the red looks a little orangey and the blue is kicked towards green. I’ve used that light lots of times on shoots though and I haven’t heard any complaints.

Those are just some impressions, please make you own decisions from the data about which lights have the best color.  I am not a colorist, just a lighting guy trying to get some objective data on these lights. I’d love to hear feedback from anyone more expert than I!

if you’re still curious, here is more information on vectorscopes and the DSC OneShot.

 

LED panel comparison: color charts, vectorscopes, light loss was last modified: by

by Tom Guiney

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