L.E.D. lighting creates stripes?
Jan 13, 2018 11:43:29 #
petercbrandt
Loc: New York City, Manhattan
Can anyone advise why L.E.D. lights lit up in a room would create horizontal stripes through a photograph ? Then I took another photo with my cellphone and there were no stripes. The 1st photo was taken with my Leica V-lux, an all-in-one digital w/ 25-400 zoom. Has anyone heard of this issue?
I will email Leica as well.
I will email Leica as well.
Jan 13, 2018 12:11:58 #
Jan 13, 2018 12:21:34 #
One possibility, if the LED light is being pulsed and your using a fast shutter speed, then a stripe will occur. The light can pulse as the shutter curtain drops. Pulsing a LED is a common and easy method of controlling perceived light intensity due to the nonlinear characteristics of LED's. If your referring to your home lights, most use this method (Pulse Width Modulation) for dimmable LED light bulbs.
If this happens all the time, then try slowing down your shutter speed.
If your light are DC, then others may have a different answer.
If this happens all the time, then try slowing down your shutter speed.
If your light are DC, then others may have a different answer.
Jan 13, 2018 12:32:07 #
Are we talking about ambient room lighting, or purpose built LED studio lighting?
Jan 13, 2018 14:43:16 #
As mentioned above, this sure sounds like the PWM dimming. If there is a brightness adjustment on the LEDs, try turning them up all the way (full brightness).
Different LED controlers achieve PWM dimming using different base frequencies. Many use 120Hz which easily interferes with 60Hz video cams (as well as your shutter at "typical" indoor speeds). I searched high and low to find the D4-XE controller for my last LED lighting project, it uses a selectable 500Hz/2000Hz multiplex frequency. Works great for most indoor shutter speeds. You can get one here if you are able to swap the controller on your LED lights:
https://www.aliexpress.com/item/4-CH-CV-MX512-RDM-Decoder-4-CH-CC-DMX512-RDM-Decoder-with-digital-display-DMX512/32838929657.html?spm=2114.10010108.1000023.40.5817721foJECzZ
It works with standard RGB or RGBW LED tape/strings and even includes DMX functionality. At $25 its a low risk investment. ;-)
Different LED controlers achieve PWM dimming using different base frequencies. Many use 120Hz which easily interferes with 60Hz video cams (as well as your shutter at "typical" indoor speeds). I searched high and low to find the D4-XE controller for my last LED lighting project, it uses a selectable 500Hz/2000Hz multiplex frequency. Works great for most indoor shutter speeds. You can get one here if you are able to swap the controller on your LED lights:
https://www.aliexpress.com/item/4-CH-CV-MX512-RDM-Decoder-4-CH-CC-DMX512-RDM-Decoder-with-digital-display-DMX512/32838929657.html?spm=2114.10010108.1000023.40.5817721foJECzZ
It works with standard RGB or RGBW LED tape/strings and even includes DMX functionality. At $25 its a low risk investment. ;-)
Jan 13, 2018 16:45:29 #
Jan 13, 2018 17:16:26 #
petercbrandt wrote:
Can anyone advise why L.E.D. lights lit up in a room would create horizontal stripes through a photograph ? Then I took another photo with my cellphone and there were no stripes. The 1st photo was taken with my Leica V-lux, an all-in-one digital w/ 25-400 zoom. Has anyone heard of this issue?
I will email Leica as well.
I will email Leica as well.
I've heard of this sort of thing with Sony cameras using "electronic shutter". What kind of shutter were you using??
Jan 13, 2018 18:06:43 #
petercbrandt
Loc: New York City, Manhattan
my digital camera must be using a digital shutter. one hedgehog member suggested a slower shutter speed. i think they may be right. i have noticed that when shooting in Program mode my camera starts up suggesting the fastest shutter speed. i'll watch that next time more carefully. thanks everybody !!!!
Jan 13, 2018 18:39:33 #
rehess wrote:
I've heard of this sort of thing with Sony cameras using "electronic shutter". What kind of shutter were you using??
This can happen with almost any digital camera. With PWM, if the dimmable LED pulses (flashes) during the time the first and second curtains are in motion (rolling shutter mode) then a horizontal stripe will be recorded. This also happens in electronic shutter mode. But the effect is slightly different because the CCD is read sequentially pixel-by-pixel, row-by-row. It's not brand specific, it's device specific.
Jan 14, 2018 07:06:12 #
rwilson1942 wrote:
LEDs do flicker. Watch a high speed - slow motion shot of LEDs, and you will see them flickering. Even regular video of cars lights will show the flicker.
https://www.youtube.com/watch?v=C12QxTJL1KU
https://www.youtube.com/watch?v=MUJydM4kO6w
https://www.youtube.com/results?search_query=flickering+leds+on+cars
Jan 14, 2018 10:03:50 #
Jan 15, 2018 05:35:15 #
https://www.youtube.com/watch?v=xWqL-xtVmuQ
This is a how to build your own LED panel. It uses a voltage regulator and a potentiometer to dim the led panel without pulsing. With this, you may be able to hack a conversion for your panel.
This is a how to build your own LED panel. It uses a voltage regulator and a potentiometer to dim the led panel without pulsing. With this, you may be able to hack a conversion for your panel.
Jan 15, 2018 09:28:10 #
SalvageDiver wrote:
This can happen with almost any digital camera. With PWM, if the dimmable LED pulses (flashes) during the time the first and second curtains are in motion (rolling shutter mode) then a horizontal stripe will be recorded. This also happens in electronic shutter mode. But the effect is slightly different because the CCD is read sequentially pixel-by-pixel, row-by-row. It's not brand specific, it's device specific.
I heard of this issue with Sony electronic shutter last summer; I have not heard of it reported for physical shutter.
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