Thoughts on these LED lights

[j1clark@ucsd.edu]

Do you have a good link to where I can learn how to use the vectorscope for this purpose? What should I be looking for? (a link is fine you don't have to type the whole thing! some people here are TOO nice

Adobe OnLocation has scopes. While it may not be a hardware solution, it may be cheaper for you.

I believe Final Cut Pro has some scopes as well.

If you have firewire capable cameras, then the OnLocation can give you the 'live' monitor function. Otherwise, you have to capture a clip, and analyze non-realtime.

 

[Tobias Deml]

I got an LED flashlight at the 99c-store ... it has 11 LEDs inside. Meaning, 500 LEDs cost less than 50$.

Did anyone here experiment with building an apparatus like that yourself? And if yes - how did you wire it?


Gentle

 

[rallymatt]

I got an LED flashlight at the 99c-store ... it has 11 LEDs inside. Meaning, 500 LEDs cost less than 50$.

Did anyone here experiment with building an apparatus like that yourself? And if yes - how did you wire it?

Why? $130 more gets you a real fixture.

 

[KevinP]

Have you checked the color balance of the fixture yet?

The one I bought from Prompter People was 4300K.

Totally unusable.

Why unusable? - Just white balance to the light.

 

[j1clark@ucsd.edu]

Why unusable? - Just white balance to the light.

I don't know what the other poster had in mind when they claimed LEDS, or at least these 'consumer' LED based lights are 'unusable', but I'd probably think if there is a problem it is not only in color temperature, but also the spectrum, as in are there any spikes or 'holes' in the spectrum, such that color's 'go weird', when illuminated with the light...

Think Sodium Vapor, which is not only a problem in 'color temperature', but it also has a narrow spectrum, and so, things end up registering as some sort of 'monochromatic' value.
(And I think some varient of that was used for a 'chromakey' type process...)

 

[GRENCH]

What do you think about this for white balance:

http://www.colorright.com - looks pretty sweet to me.

I don't understand something - the Auto WB averages for 18% gray so when I use the custom WB do I need to use a 18% card or a white card ?! Whats the white card for and whats the gray card is for?!?

It worked great for me. I was shooting in Puerto Rico and had to get a gaffer I meant there to rig a softly lit scene using a home made tandom series of light defusion. We had a number of different temperatures ranging from 3200k to 4300k. This Color Right temperature corrector was a big help.
Chack out the raw footage. No perfect but far better than to results I was getting with out using the ColorRight corrector.

http://www.colorright.com

Hey Grench,
For some reason I'm not getting notified of posts.
I'm still doing some comparisons but a simple -5 on the green axis does a good job.
I used that setting on an film interview last week, the subject was very pale which can show the green cast pretty well, and it looked good.
I've been shooting outdoor locations this week so no LEDs, but I want to try some variations when I get back.
An easy way to test is to sit a subject and do a bunch of variations as stills, load them on your screen and use a well balanced image as a reference.
It helps to narrow it down quickly for the next batch.
Anyway, a simple -5 to -7 green certainly works well for starters.

Thanks jimagin! I will try this setting out.

 

[KevinP]

Gray card for exposure white card for WB, got it!

Yes but not 100% essential - you will get the same white balance from a grey card as you will from a white card. This is because the grey card has no colour bias - same as a white card.

The grey card is exposed at 50-55% and the white card 95%~ - exposing one will give you the other.

White balancing from cards tinted R G or B will give you a (opposite) cooler or warmer image.

 

[I_am_Thunderslam]

I just bought a set of the 500 LEDs and one 1000 LED, the lights aren't too bad! If you want to read it, here is a review I put up a while back. All my tests were with done the Panasonic AF100.


I just received my set of 3 Ephoto(also known as Fancier and a million other names) LED 500 lights a 100 LED light. I was a bit skeptical about buying these at first, but after reading a good review by the guys at cheesycam I couldn't help myself, these lights were so cheap and lit so well, even when put up against a Litepanel!
Ok, so I received them and I immediately set them up. I had heard that the lights have a bit of a green spike, so I also picked up some 1/4 minus green gels, just for the sake of safety.

As I began my set up, I noticed that the lights used something of a regular computer power cable to power the lights, this makes me wish I'd have ordered the lights with the dimmer, as they have a 12v DC input as well as XLR power inputs, however, they cost a smidge more than I'd prefer to spend on a gamble such as this. The good thing about the lights I have is that at least they are only 50w a piece, which will make it easy to find a cheap source to power them, such as an inverter connected to a car battery or a small 1000w generator will do(which will also power most all of your other stuff too! stick with a Honda generator, they are the quietest from my experiences.)

The build of the lights are quite solid, a bit thicker than your Litepanels, but good enough. There are also some flimsy barn doors and some handy rails along the sides of the lights for easy mounting at any angle. Unfortunately there is no dimmer on these lights, only 4 channels in which you can control by flipping switches to reduce the amount of projected light.(If that sounds difficult to imagine, it's ok, I'll show them in the video)


For my initial tests I used a Panasonic AF100(which I will post later). The three 500 LED lights can easily brighten a 12x15 room, which to me has already proven it's worth if I say so myself! When i post my footage, you will see that I will cycle through the F-Stops on a Nokton 25mm 0.95, Tokina 11-16mm 2.8, and a Zeiss 50mm 1.4 ZF.2(this lens has a cine mod, so I will just smoothly and slowly dial the iris for you).

All in all, I say that these lights are quite the deal, even though I do wish that I would have gone with the dimmable lights as they seem to have more features. I think I may get the LED 600 or 900 next, which have built on V-mount battery connections as well as the dimmer, and the 12 dc out!