LED Flicker on Video

[Uriahdemon]

Hi, I have recently bought the following PARS and have been using them without issue for a little while now. http://www.prolight.co.uk/ftp-in/LEDJ210_Manual.pdf

 

I have a show coming up and a couple of the chaps who intend to video it say they have experienced LED flicker off these fixtures. Is there any quick fix for this or do I need to get some different PARS.....??

[Caerdydd]

Depending on the quality of the cameras and the adjustments available on them it may be possible to dial in a shutter value that will remove the flickering. Failing that then it would be changing the fixture.

 

Would it be fair to say they are lower end led pars?

[indyld]

The solution is either to adjust the camera shutter if possible or the hack is to fiddle with the LED intensities until it goes away. All LEDs flicker if they have a dimming capability and as a general rule, the cheaper they are the more obvious it is - particularly on camera.

[timsabre]

Lock camera shutters at 1/50 and will be fine. Unfortunately some cameras will adjust exposure by raising the shutter speed and higher shutter speeds will show up flicker in the leds.

[Dave m]

LED lighting in theatres does tend to flicker more than LED lights for film and TVThe colours also tend to look weird to the camera

 

I did a gig at the Brighton Dome a few years ago where the stage preset was a blue and there was a red carpet.Blue lighting always tends to bleed on camera but the red carpet went into a kind of purple acid tripIt looked fine to the eye

Once the show got going it was ok as more white light came up but I had a few nervous moments

[Karel Bata]

You're in the UK with a 50Hz mains source?

But actually that shouldn't really make any difference as the unit gives the LEDs a 400Hz refresh rate. So is your camera perhaps set to 30fps, or (a bit fancy) 24fps? Try 25 or something that divides into 400, and the shutter set to 180 degrees. The lamp could be faulty. It happens.

[timsabre]

But actually that shouldn't really make any difference as the unit gives the LEDs a 400Hz refresh rate. So is your camera perhaps set to 30fps, or (a bit fancy) 24fps? Try 25 or something that divides into 400, and the shutter set to 180 degrees. The lamp could be faulty. It happens.

All led fixtures are different. You can't rely on it being 400Hz, especially the cheaper ones. I had some with a 150Hz refresh which I could see by eye.

 

[Karel Bata]

I'm only going by the spec sheet the OP posted - see up top.

 

I've no idea how reliable Ledj fixtures are, but if the spec says 400Hz and it turns out not to be I'd send it back.

[dmxlights]

I have the (6) LEDj Q colour as well. I have also had the same problem as the OP and I also have other LEDj lights and I have no problem with them. I also have cheep LEDj lights and mean cheap they where 30.00 pound each and I have no problem with them at all. Even my showtec led bars do not cause any problems.

I have taken all the led lights I have as RGB or RGBW and have done tests with them and out of all the only one that I had problems with is the LEDj Q colour.

 

here is a list of lights that I have or tried.

 

Showtc lightbar 12 LEDj led zoomLEDj BurstStairville LED Flood panel 150LEDj Q Colour

Showtec LED par can (par 64)Cameo CLP64Q8W

Out of the above list the only one that causes any problem is LEDj Q Colour

 

 

I have tried other Q Colours that I do not own and they also do the same. So it not been down to been cheap they are just a bad design. I have listed cheap led lights in my list and do not have any problems with them

Edited January 27, 2020 by dmxlights

[Uriahdemon]

On 1/27/2020 at 6:17 PM, dmxlights said:

I have the (6) LEDj Q colour as well. I have also had the same problem as the OP and I also have other LEDj lights and I have no problem with them. I also have cheep LEDj lights and mean cheap they where 30.00 pound each and I have no problem with them at all. Even my showtec led bars do not cause any problems.

I have taken all the led lights I have as RGB or RGBW and have done tests with them and out of all the only one that I had problems with is the LEDj Q colour.

 

here is a list of lights that I have or tried.

 

Showtc lightbar 12 LEDj led zoomLEDj BurstStairville LED Flood panel 150LEDj Q Colour

Showtec LED par can (par 64)Cameo CLP64Q8W

Out of the above list the only one that causes any problem is LEDj Q Colour

 

 

I have tried other Q Colours that I do not own and they also do the same. So it not been down to been cheap they are just a bad design. I have listed cheap led lights in my list and do not have any problems with them

Thanks for this.  I totally forgot I posted this one night hence the extremely late reply

[Uriahdemon]

Thanks very much to everyone for their helpful input to my issue. I apologise for coming back months later on this however as we all know the urgency to get my lights up to speed kind of blew away on the breeze.....  Like many of us.

I now want to get something done about the problem and bought a brand new LED PAR to test.  This has a refresh rate of 17.7 Khz as opposed to the problem child which was 400hz.  I video'd the old PARS which had the flicker and then the new one on an iphone but on reviewing the video could not see any flicker.

Has anyone got any good ideas for testing lights for flicker please....??

Edited December 23, 2021 by Uriahdemon

[Dave m]

iPhones vary the shutter speed instead of varying the iris- basically they don’t have one.

so using a phone to check is a waste of time

[Uriahdemon]

4 minutes ago, Dave m said:

iPhones vary the shutter speed instead of varying the iris- basically they don’t have one.

so using a phone to check is a waste of time

Thanks Dave, that is much appreciated.  I will give my digital camera a go.