GH2 How do you fix this? (Video)

The LEDs are flickering because of the frequency at which they normally cycle (usually around 60Hz, but I'm not sure for that keyboard). What FPS/shutter speed are you shooting? If you're shooting at 24p, try a shutter speed of 1/40. A more detailed explanation of what's happening is below, if you happen to be interested:

When you see an LED glowing, it's not actually continuously emitting light - it flickers on and off very quickly in order to appear like it is, usually something like 60 times a second. So if you're filming and your shutter speed is faster than the frequency of the LEDs, you can capture frames where the LED is off, making it look flickery on the resulting recording. Dropping your shutter speed should help somewhat, as it means there's more time for the LED to turn back on for any given frame and emit light to the sensor, making the LED appear lit in each frame.
 
I was shooting at 1/125 because im recording 720p/60fps.

Ive been told you want x2 fps for shutter speed.

if i lower it like you said, it does goes away but is this optimal?
 
It's your only option for removing this sort of issue, unfortunately. How low do you have to go to get rid of it in this situation? Anything 1/120-1/100 should be OK.
 
aonavy said:
I dont think I have had this issue in the past.

the leds on PC blink. why is this?

GH2 with flow motion hack

filmed with 4.5mm-12mm CCTV lens

http://youtu.be/XrFULm78Ge4?hd=1

thanks
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Reading your questions on the forum, I'd politely say that you should spend the weekend researching and reading all you can about dslr shooting and the GH2.
its best to research all you can and try and soak it all up!
 
This is a general filmmaking issue not GH2 related. You would get the same problem with a Red or an Alexa. You will see this same sort of issue with Neon lights and some street lights as well. The only solution is to lower your shutter speed.
 
IronicCatfish said:
When you see an LED glowing, it's not actually continuously emitting light - it flickers on and off very quickly in order to appear like it is
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That doesn't sound right, especially with LED lights being in pretty common usage as on-camera and set lights these days.
 
Jim Simon said:
That doesn't sound right, especially with LED lights being in pretty common usage as on-camera and set lights these days.
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Fortunately, there are flicker-free LED lights on the market, which are also called rectified lights. They turn on and off (flicker) even more rapidly than non-rectified lights, at a rate of about 120 Hz per second. The flicker of rectified LED lights is virtually undetected by the human eye, and even though they flicker, they are called non-flickering or flicker-free. It would be more accurate to say they are imperceptible flickering lights! Unfortunately, rectified LED lights are less efficient than non-rectified lights, which is still a small price to pay since they are so much more efficient than any other type of light on the market anyway. Another ‘bonus’ of rectified lights is that they are much brighter than the non-rectified lights, by as much as 30% – 40%.
 
DPStewart said:
Fortunately, there are flicker-free LED lights on the market, which are also called rectified lights. They turn on and off (flicker) even more rapidly than non-rectified lights, at a rate of about 120 Hz per second. The flicker of rectified LED lights is virtually undetected by the human eye, and even though they flicker, they are called non-flickering or flicker-free. It would be more accurate to say they are imperceptible flickering lights! Unfortunately, rectified LED lights are less efficient than non-rectified lights, which is still a small price to pay since they are so much more efficient than any other type of light on the market anyway. Another ‘bonus’ of rectified lights is that they are much brighter than the non-rectified lights, by as much as 30% – 40%.
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good information right there!!

Thank you
 
aonavy said:
the flicker calc is great! Thank you


Ive never knew about this. I dont have many LED lights. Thank for all the information you have provided
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But really this goes for any type of light. Except it wouldn't be a flicker for other types-- it would just make a weird repeating wave appear on the video. This is why you typically want to shoot at 1/60 in 60 Hz countries and 1/50 in 50 Hz countries.
 
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