Light Experiment

900rr · Dec 17, 2013

Hi everyone
I am experimenting with light painting as you can see below

. I was wondering if someone could recommend specific light source that performs better than other, and ISO recommended for this type of photography. Attached pictures are made with LED light. Thank you in advance .

deeky · Dec 17, 2013

LED is what makes it a dashed line rather than a solid one - just the way they work. If you want a solid line find a light with a regular incandescent light bulb. Not sure if that is what you are asking, but there you go.

Braineack · Dec 17, 2013

LEDs emits light on a wavelength, and not a continuous light like a filament bulb would, so you're capturing that when you move the LED rapidly.

Geaux · Dec 17, 2013

ISO low and shutter long. Draw to hearts content.

Josh66 · Dec 17, 2013

Just move the light more slowly...?

I've done this with an LED light and never noticed any breaks in the line...

I do need to mess around with it some more though. That was a test for a shot I planned on doing, but never actually did.

It was ISO 100, f/8, and probably around 4 minutes.

480sparky · Dec 17, 2013

Braineack said:
LEDs emits light on a wavelength, and not a continuous light like a filament bulb would, so you're capturing that when you move the LED rapidly.

Um... a wavelength does not just 'turn on and off' all by itself.

Plus, the filament of a normal bulb in your house, actually DOES pulse due to the AC sine wave.

My guess is the OP is using an AC-to-DC converter to drive the LED. If so, it's going through a rectifier that may cause the pulsing.

minicoop1985 · Dec 17, 2013

I have some sort of LED flashlight I bought years ago because they're indestructible (was doing HVAC work and going through a plastic flashlight a week) called an LED Lenser or something similar that works VERY well for this kind of thing. Now that I know what white balance is :lol:

I should reshoot some of my light painting car pics. Anyway, you've got a good grasp on it, it looks like. I like how the first one looks like a globe.

Braineack · Dec 18, 2013

Sorry, I didn't mean wavelength so much as the low refresh rate they cycle at, probably, 60Hz. 60Hz means it recycles every 60th of a second, which is pretty slow and the refresh rate can be captured if you move them fast enough on a long exposure--it's literally pulsing.

Incandescent bulbs glow from a hot wire--it's always glowing--so no matter how fast you move the bulb, it won't produce a pattern in that manner.

amolitor · Dec 18, 2013

Dimmable handheld LED lights (headlamps, flashlights) turn the LED on and off, at variable rates. Varying the duty cycle is how they adjust the apparent brightness.

Some other LED lights will be continuous, some will be pulsed. It depends on how the thing is powered. There's noting inherent to LEDs that prevent them from producing continuous light.

Braineack · Dec 18, 2013

gotcha. I just know enough to get myself into trouble.

deeky · Dec 18, 2013

I'm with you Braineack. I know led Christmas lights will flash. Plug a string in and twirl it. From what I am gathering, battery operated lights are DC, so will not flash? Or is it the electronics of the led and not that power source that make them cycle?

Hope this doesn't come off as a highjack - question was about light source.

minicoop1985 · Dec 18, 2013

Apparently it depends on the light source. My battery powered LED flashlights don't pulse like that (I have a few junky ones in addition to my good one). I have seen ones that do pulse though.