LED lighting causing banding on A7s at new venues. at DVinfo.net

Michael Bradshaw · May 4th, 2015, 10:54 AM

Hi, a couple of the new venues I've been to lately seem to be using LED uplighters in the ceiling to provide ambient light. It looks very nice and all that but it's a nightmare for the cameras. I'm getting very noticeable banding on my A7s, not quite so obvious on the FS100's, but still too noticeable for my liking.

I'm certain a client is going to comment on this eventually. Any ideas what I can do in terms of camera settings or even in post?

For those of those local, it's Galgorm and The Merchant that are most obvious. I'm worried that as more venues are refurbished this is going to become a more frequent issue.

Thanks, M

Peter Rush · May 4th, 2015, 11:26 AM

I've had similar and not just with the A7s but with the NEX EA50 at a venue in Halifax - Awful LED lights all across the ceiling behind drapes - in certain areas of the room I got strobing which I could not resolve despite trying many shutter speeds.

Paul R Johnson · May 4th, 2015, 11:52 AM

A lot of these have rather strange implementation of PWM dimming - and you may find one of the shutter speeds more friendly to it. However, many different types of LED product may be in action, so some could be made more steady and the others get worse.

Michael Silverman · May 4th, 2015, 12:52 PM

Here's a helpful article on flicker from LED lights:

David Satz - Gaffer, Lighting Designer - About flicker problems

I've read that DSLRs are more prone to this than traditional video cameras and cinema cameras. I shot a wedding last year and my 70D picked up an LED flicker but my C100 did not which sounds similar to your experience with the FS100 not showing the flicker.

Clive McLaughlin · May 4th, 2015, 01:13 PM

Quote:

Originally Posted by Michael Bradshaw

Hi, a couple of the new venues I've been to lately seem to be using LED uplighters in the ceiling to provide ambient light. It looks very nice and all that but it's a nightmare for the cameras. I'm getting very noticeable banding on my A7s, not quite so obvious on the FS100's, but still too noticeable for my liking.

I'm certain a client is going to comment on this eventually. Any ideas what I can do in terms of camera settings or even in post?

For those of those local, it's Galgorm and The Merchant that are most obvious. I'm worried that as more venues are refurbished this is going to become a more frequent issue.

Thanks, M

Hi Michael - Galgorm Renaissance Suite by any chance???

I always get flicker and banding there. Really annoys me - no shutter speed eliminates it.

Clive McLaughlin · May 4th, 2015, 01:14 PM

Ha, just read you already stated its the Galgorm. I mentioned this on our NI videographer group ages ago? Are you in it? I'll send you an invite.

Anthony McErlean · May 4th, 2015, 01:43 PM

Quote:

Originally Posted by Michael Bradshaw

For those of those local, it's Galgorm , M

Is that Galgorm Ballymena?

Michael Bradshaw · May 4th, 2015, 04:52 PM

Yup, The prestigious Galgorm resort and Spa as James says! Yes Anthony, near Ballymena.

And yes Clive, its that new suite upstairs. The Four Seasons suite isn't too bad but the main room in the Merchant has them as well. It's a real pain. I may have add something to my contract or start mentioning it to clients.

Michael Bradshaw · May 4th, 2015, 04:54 PM

Even worse is the way they make the guests faces all blurry? Har, Har.

Clive McLaughlin · May 5th, 2015, 06:27 AM

I mentioned it to James one time - not a complaint, just happened to say. He was not impressed!

I wonder if they are dimmable, and maybe if the dimmer switches were adjusted slightly it might help.

I only got that banding, near the front entrance of the Renaissance Suite, but lighting around teh ceiling edge in main room flickers like crazy when it's ever in shot.

Paul R Johnson · May 5th, 2015, 08:20 AM

I'd bet they're too bright, so they've been dimmed severely! Some of the newer LED are too bright on DMX level 1 our of 255!

Christopher Young · May 6th, 2015, 11:41 AM

As a lot of you are saying this LED lighting is becoming more and more of an issue for a lot of shooters. Read the following from lighting gaffa David Satz and weep bearing in mind that 0 = no flicker and 99 = massive flicker:

"LED lights

LED lights are different from the classical light sources we discussed so far. LEDs react very fast to voltage changes, even faster than discharge lamps, therefore LEDs are flicker waiting to happen! Similar to the other lights, it depends on the power supply, how strong the flicker is. LEDs usually are supplied by d.c. voltage provided by a mains adapter. Quality adapters generate a very well stabilized voltage, providing flicker-free light. Cheap adapters have a certain ripple, similar to electronic fluorescent ballasts. LED lights can also be operated on transformers or connected in series directly on mains power (for example christmas lights). These lights are flickering intensively.

Serious trouble starts, when LED lights are dimmed. LEDs usually are dimmed by chopping the d.c. supply voltage and varying on and off time. This leads to a massive flicker, even when using quality mains adapters. This not only applies to dimming (for example car stop lights), but also to multicolor LEDs. These LEDs consist of several individual LEDs of different colors. When displaying non-primary colors, the different color channels are dimmed.

For incomprehensible reasons, many manufacturers use frequencies different from the mains frequency for dimming, usually between 30 and 200 Hz. This leads to serious flicker problems, even when shooting on 24 fps! So always measure the flicker factor AND the frequency when shooting with LED lights.

Typical flicker factors of LED lights:
lamp type flicker-factor
LED dimmed at 50%: 99 %
LED on transformers: 40 - 70 %
LED, low cost supply: 0 - 15 %
LED, quality supply: 0 - 3 %"

He has some suggestions on how to minimise the flicker issues with his tables of safe shutter speeds / angles at various frame rates on his web site at:

David Satz - Gaffer, Lighting Designer - About flicker problems

Regardless I still find dimmed LEDs are often a disaster to shoot with in some modern and updated venues. My 1'x1' LED panels have dimmers and are flicker free so flicker free LED lighting can be achieved. Sad but true these venues are obviously driven by the bottom line which often means the cheapest solution and in the process video production requirements don't even get a look in.

Chris Young
CYV Productions
Sydney

May 4th, 2015, 10:54 AM	#1
Michael Bradshaw Regular Crew Join Date: May 2010 Location: Newtownabbey, UK Posts: 66	LED lighting causing banding on A7s at new venues. Hi, a couple of the new venues I've been to lately seem to be using LED uplighters in the ceiling to provide ambient light. It looks very nice and all that but it's a nightmare for the cameras. I'm getting very noticeable banding on my A7s, not quite so obvious on the FS100's, but still too noticeable for my liking. I'm certain a client is going to comment on this eventually. Any ideas what I can do in terms of camera settings or even in post? For those of those local, it's Galgorm and The Merchant that are most obvious. I'm worried that as more venues are refurbished this is going to become a more frequent issue. Thanks, M Attached Thumbnails

May 4th, 2015, 11:26 AM	#2
Peter Rush Inner Circle Join Date: Nov 2008 Location: UK/Yorkshire Posts: 2,069	Re: LED lighting causing banding on A7s at new venues. I've had similar and not just with the A7s but with the NEX EA50 at a venue in Halifax - Awful LED lights all across the ceiling behind drapes - in certain areas of the room I got strobing which I could not resolve despite trying many shutter speeds.

May 4th, 2015, 11:52 AM	#3
Paul R Johnson Inner Circle Join Date: Nov 2005 Location: Lowestoft - UK Posts: 4,045	Re: LED lighting causing banding on A7s at new venues. A lot of these have rather strange implementation of PWM dimming - and you may find one of the shutter speeds more friendly to it. However, many different types of LED product may be in action, so some could be made more steady and the others get worse.

May 4th, 2015, 12:52 PM	#4
Michael Silverman Major Player Join Date: Nov 2014 Location: Charlottesville Posts: 255	Re: LED lighting causing banding on A7s at new venues. Here's a helpful article on flicker from LED lights: David Satz - Gaffer, Lighting Designer - About flicker problems I've read that DSLRs are more prone to this than traditional video cameras and cinema cameras. I shot a wedding last year and my 70D picked up an LED flicker but my C100 did not which sounds similar to your experience with the FS100 not showing the flicker.

May 4th, 2015, 01:14 PM	#6
Clive McLaughlin Major Player Join Date: Sep 2012 Location: Belfast Posts: 823	Re: LED lighting causing banding on A7s at new venues. Ha, just read you already stated its the Galgorm. I mentioned this on our NI videographer group ages ago? Are you in it? I'll send you an invite.

May 4th, 2015, 04:52 PM	#8
Michael Bradshaw Regular Crew Join Date: May 2010 Location: Newtownabbey, UK Posts: 66	Re: LED lighting causing banding on A7s at new venues. Yup, The prestigious Galgorm resort and Spa as James says! Yes Anthony, near Ballymena. And yes Clive, its that new suite upstairs. The Four Seasons suite isn't too bad but the main room in the Merchant has them as well. It's a real pain. I may have add something to my contract or start mentioning it to clients.

May 4th, 2015, 04:54 PM	#9
Michael Bradshaw Regular Crew Join Date: May 2010 Location: Newtownabbey, UK Posts: 66	Re: LED lighting causing banding on A7s at new venues. Even worse is the way they make the guests faces all blurry? Har, Har.

May 5th, 2015, 06:27 AM	#10
Clive McLaughlin Major Player Join Date: Sep 2012 Location: Belfast Posts: 823	Re: LED lighting causing banding on A7s at new venues. I mentioned it to James one time - not a complaint, just happened to say. He was not impressed! I wonder if they are dimmable, and maybe if the dimmer switches were adjusted slightly it might help. I only got that banding, near the front entrance of the Renaissance Suite, but lighting around teh ceiling edge in main room flickers like crazy when it's ever in shot.

May 5th, 2015, 08:20 AM	#11
Paul R Johnson Inner Circle Join Date: Nov 2005 Location: Lowestoft - UK Posts: 4,045	Re: LED lighting causing banding on A7s at new venues. I'd bet they're too bright, so they've been dimmed severely! Some of the newer LED are too bright on DMX level 1 our of 255!

May 6th, 2015, 11:41 AM	#12
Christopher Young Trustee Join Date: Apr 2008 Location: Sydney Australia Posts: 1,567	Re: LED lighting causing banding on A7s at new venues. As a lot of you are saying this LED lighting is becoming more and more of an issue for a lot of shooters. Read the following from lighting gaffa David Satz and weep bearing in mind that 0 = no flicker and 99 = massive flicker: "LED lights LED lights are different from the classical light sources we discussed so far. LEDs react very fast to voltage changes, even faster than discharge lamps, therefore LEDs are flicker waiting to happen! Similar to the other lights, it depends on the power supply, how strong the flicker is. LEDs usually are supplied by d.c. voltage provided by a mains adapter. Quality adapters generate a very well stabilized voltage, providing flicker-free light. Cheap adapters have a certain ripple, similar to electronic fluorescent ballasts. LED lights can also be operated on transformers or connected in series directly on mains power (for example christmas lights). These lights are flickering intensively. Serious trouble starts, when LED lights are dimmed. LEDs usually are dimmed by chopping the d.c. supply voltage and varying on and off time. This leads to a massive flicker, even when using quality mains adapters. This not only applies to dimming (for example car stop lights), but also to multicolor LEDs. These LEDs consist of several individual LEDs of different colors. When displaying non-primary colors, the different color channels are dimmed. For incomprehensible reasons, many manufacturers use frequencies different from the mains frequency for dimming, usually between 30 and 200 Hz. This leads to serious flicker problems, even when shooting on 24 fps! So always measure the flicker factor AND the frequency when shooting with LED lights. Typical flicker factors of LED lights: lamp type flicker-factor LED dimmed at 50%: 99 % LED on transformers: 40 - 70 % LED, low cost supply: 0 - 15 % LED, quality supply: 0 - 3 %" He has some suggestions on how to minimise the flicker issues with his tables of safe shutter speeds / angles at various frame rates on his web site at: David Satz - Gaffer, Lighting Designer - About flicker problems Regardless I still find dimmed LEDs are often a disaster to shoot with in some modern and updated venues. My 1'x1' LED panels have dimmers and are flicker free so flicker free LED lighting can be achieved. Sad but true these venues are obviously driven by the bottom line which often means the cheapest solution and in the process video production requirements don't even get a look in. Chris Young CYV Productions Sydney