How to prevent/minimize banding with electronic shutter?

[FrederikB]

I like to shoot bands and artists and usually I use the mechanical shutter. But in this specific case, the performance was acoustic so I used the electronic shutter instead, to not disturb the performers.

But the stage was lit by artificial lights and the image shows heavy banding. How do I prevent this (or minimize the unwanted effect)? It looks like there are 3 different frequencies with the light(s).

 

[D Cox]

I think you have to upgrade to a Z9, or wait until a similar fast sensor appears in a cheaper model.

Meanwhile try shooting at 1/50 second.

Don

 

[Tom Axford]

I would suggest that you post this question in the appropriate Nikon forum. That banding does not look like the usual banding got with most cameras using electronic shutter with artificial lighting. I wonder if it is something camera specific.

 

[iljitsch]

This is because the sensor readout is slower than the speed at which the lights flicker. Indeed a Z9 with its fast sensor readout would do the trick.

Often, in video mode, sensor readout is faster in lower resolutions. Perhaps this also works in stills mode. So reduce your resolution and see if you get better results.

I'll see if I can test with my Nikon Z fc tonight after dark.

 

[iljitsch]

This is because the sensor readout is slower than the speed at which the lights flicker.

...and the shutter speed is faster than the light flicker frequency. If you cut your shutter speed to 1/60 or 1/50 or slower you're probably good.

Often, in video mode, sensor readout is faster in lower resolutions. Perhaps this also works in stills mode. So reduce your resolution and see if you get better results.

I'll see if I can test with my Nikon Z fc tonight after dark.

Didn't work:


Large


Small

But... you can also take stills in video mode:


4K 30 FPS but long shutter time


4K 30 FPS with the same 1/4000 shutter speed like all the others with the banding


HD (1920x1080) 120 FPS

 

[FrederikB]

Thanks for the help everyone. So it's related to the readout speed. Found the specs, 1/20 sec on my Z6 II and 1/270 on the Z9. That's a big difference

1/60 shutter speed would probably induce motion blur in my shots. Would 1/120 help in this case? Or 1/180?

 

[D Cox]

Thanks for the help everyone. So it's related to the readout speed. Found the specs, 1/20 sec on my Z6 II and 1/270 on the Z9. That's a big difference

1/60 shutter speed would probably induce motion blur in my shots. Would 1/120 help in this case? Or 1/180?

Unlikely.

A bit of motion blur is not a disaster; banding is.

Don

 

[iljitsch]

1/60 shutter speed would probably induce motion blur in my shots. Would 1/120 help in this case? Or 1/180?

Depends. My tests were done with Philips Hue lights, which have RGB LEDs that light up in sequence at about 500 cycles per second. So that's higher end LED lights with a high frequency.

Cheaper LED and fluorescent lights usually cycle along with the mains power, so that would be 50 or 60 Hz, but there is often a side effect of the electronics that doubles this frequency. So you could be good up to 1/125 in 60 Hz countries. (Although 2 x 60 = 120 vs 125 could still create some banding.)

I'd say take some test shots and lower your shutter speed until the banding is no longer a problem, and then simply "spray and pray" (i.e., take a bunch of shots quickly) in the hopes that you get a good one with no or little motion blur.

I think with most music 1/60 is fine except for some motion blur in the hands playing the instruments.

Mirrorless cameras often have a "flicker reduction" feature where I believe they try to sync up the shutter with the flicker cycle of the lights. That probably helps, but maybe it doesn't, so try with this and off and see what's better.

 

[John Sheehy]

This is because the sensor readout is slower than the speed at which the lights flicker. Indeed a Z9 with its fast sensor readout would do the trick.

Often, in video mode, sensor readout is faster in lower resolutions. Perhaps this also works in stills mode. So reduce your resolution and see if you get better results.

Cameras generally (if not always) use full sensor readout for stills, and then downsample them for lower resolution, so smaller stills is not the solution. With video, lines may be skipped to improve on frame rate with a limited bandwidth, but that increases aliasing.

 

[John Sheehy]

Thanks for the help everyone. So it's related to the readout speed. Found the specs, 1/20 sec on my Z6 II and 1/270 on the Z9. That's a big difference

1/60 shutter speed would probably induce motion blur in my shots. Would 1/120 help in this case? Or 1/180?

Not unless the light cycles at 120Hz from a 60Hz power supply, in which case 1/120 would work perfectly. 1/180 would give banding, albeit muted compared to a much faster shutter speed.

There's no way around unchangeable strobed lighting with a slow rolling shutter, other than tailoring your shutter speed to the lights. You should consider shutter speed even with a faster rolling shutter.

This is not a simple matter of the shutter speed being slower per se; in the above scenario where 1/120 would work, 1/100 would also show banding; just a bit muted. 1/60, 1/40, and 1/30 would be perfect also like 1/120, but anything in-between will have muted banding, and the general trend is more muting as the shutter speed decreases (exposure time increases) relative to the strobing period.

I don't know if any cameras offer exactly 1/120, so there may be some very muted banding with the closest match (whatever "1/125" is, exactly). Camera shutter speeds can be slightly different than the rounded standard values.

--
Beware of correct answers to wrong questions.
John
http://www.pbase.com/image/55384958.jpg

 

[FrederikB]

1/60 shutter speed would probably induce motion blur in my shots. Would 1/120 help in this case? Or 1/180?

Depends. My tests were done with Philips Hue lights, which have RGB LEDs that light up in sequence at about 500 cycles per second. So that's higher end LED lights with a high frequency.

Cheaper LED and fluorescent lights usually cycle along with the mains power, so that would be 50 or 60 Hz, but there is often a side effect of the electronics that doubles this frequency. So you could be good up to 1/125 in 60 Hz countries. (Although 2 x 60 = 120 vs 125 could still create some banding.)

I'd say take some test shots and lower your shutter speed until the banding is no longer a problem, and then simply "spray and pray" (i.e., take a bunch of shots quickly) in the hopes that you get a good one with no or little motion blur.

I think with most music 1/60 is fine except for some motion blur in the hands playing the instruments.

Mirrorless cameras often have a "flicker reduction" feature where I believe they try to sync up the shutter with the flicker cycle of the lights. That probably helps, but maybe it doesn't, so try with this and off and see what's better.

There is a flicker reduction mode in the Z6 II but unfortunately this does not work when the silent shutter is enabled

 

[MCLV]

1/60 shutter speed would probably induce motion blur in my shots. Would 1/120 help in this case? Or 1/180?

Depends. My tests were done with Philips Hue lights, which have RGB LEDs that light up in sequence at about 500 cycles per second. So that's higher end LED lights with a high frequency.

Cheaper LED and fluorescent lights usually cycle along with the mains power, so that would be 50 or 60 Hz, but there is often a side effect of the electronics that doubles this frequency. So you could be good up to 1/125 in 60 Hz countries. (Although 2 x 60 = 120 vs 125 could still create some banding.)

I'd say take some test shots and lower your shutter speed until the banding is no longer a problem, and then simply "spray and pray" (i.e., take a bunch of shots quickly) in the hopes that you get a good one with no or little motion blur.

I think with most music 1/60 is fine except for some motion blur in the hands playing the instruments.

Mirrorless cameras often have a "flicker reduction" feature where I believe they try to sync up the shutter with the flicker cycle of the lights. That probably helps, but maybe it doesn't, so try with this and off and see what's better.

There is a flicker reduction mode in the Z6 II but unfortunately this does not work when the silent shutter is enabled

The way this feature works means that it wouldn't help for light sources with high frequency flicker and neither in electronic shutter mode with slow readout.

 

[Dem Bell]

Thanks for the help everyone. So it's related to the readout speed. Found the specs, 1/20 sec on my Z6 II

Something doesn't quite add up. Fluorescent light flickers 120 times a second in the US and 100 times a second in Europe, which means that you would expect to see 120/20 = 6 bands in the US and 100/20 = 5 bands in Europe.

The light source is some kind of coloured LED light that left 14 bands in the image in the OP. Why 14? Either the read out time is much slower than 1/20 sec or the flickering frequency is much higher than 100 Hz or 120 Hz.

Frederik, what's the mains frequency where you took this image, 50 Hz or 60 Hz?

and 1/270 on the Z9. That's a big difference

But is still a rolling shutter, so is not going to help here much. It will catch one broad band rather than 14 narrow ones.

1/60 shutter speed would probably induce motion blur in my shots. Would 1/120 help in this case? Or 1/180?

Are you in the US? Under fluorescent lighting that flickers at 120Hz, shutter speeds of 1/120, 1/60, 1/40, 1/30 would catch the whole number of light flicks and will remove the banding. But I am not sure what is going to happen under this weird coloured LED lighting that seems to be flickering at about 20*14 = 280 Hz.

 

[FrederikB]

Thanks for the help everyone. So it's related to the readout speed. Found the specs, 1/20 sec on my Z6 II

Something doesn't quite add up. Fluorescent light flickers 120 times a second in the US and 100 times a second in Europe, which means that you would expect to see 120/20 = 6 bands in the US and 100/20 = 5 bands in Europe.

The light source is some kind of coloured LED light that left 14 bands in the image in the OP. Why 14? Either the read out time is much slower than 1/20 sec or the flickering frequency is much higher than 100 Hz or 120 Hz.

Frederik, what's the mains frequency where you took this image, 50 Hz or 60 Hz?

and 1/270 on the Z9. That's a big difference

But is still a rolling shutter, so is not going to help here much. It will catch one broad band rather than 14 narrow ones.

1/60 shutter speed would probably induce motion blur in my shots. Would 1/120 help in this case? Or 1/180?

Are you in the US? Under fluorescent lighting that flickers at 120Hz, shutter speeds of 1/120, 1/60, 1/40, 1/30 would catch the whole number of light flicks and will remove the banding. But I am not sure what is going to happen under this weird coloured LED lighting that seems to be flickering at about 20*14 = 280 Hz.

Photo was taken in The Netherlands which has a 50 hz frequency.

I found a LED light inside my home and took some photo's. With shutter speeds 1/80 and below I have no banding.

With shutter speed of 1/100 I have banding in the EVF but not on the picture itself. Everything faster than 1/100 I have banding in the EVF and the picture itself.

So 1/100 or 1/80 seems to be the sweet spot.

 

[Dem Bell]

Thanks for the help everyone. So it's related to the readout speed. Found the specs, 1/20 sec on my Z6 II

Something doesn't quite add up. Fluorescent light flickers 120 times a second in the US and 100 times a second in Europe, which means that you would expect to see 120/20 = 6 bands in the US and 100/20 = 5 bands in Europe.

The light source is some kind of coloured LED light that left 14 bands in the image in the OP. Why 14? Either the read out time is much slower than 1/20 sec or the flickering frequency is much higher than 100 Hz or 120 Hz.

Frederik, what's the mains frequency where you took this image, 50 Hz or 60 Hz?

Photo was taken in The Netherlands which has a 50 hz frequency.

I found a LED light inside my home and took some photo's. With shutter speeds 1/80 and below I have no banding.

With shutter speed of 1/100 I have banding in the EVF but not on the picture itself. Everything faster than 1/100 I have banding in the EVF and the picture itself.

So 1/100 or 1/80 seems to be the sweet spspot.

The 1/80 should still show some weak banding. There will be no obvious dark bands like you see at say 1/200, but there will be smooth variation of light across the image. 1/100 should be noticeably better.

How many bands do you see in the images at high shutter speeds? Is it about 5?

 

[lehill]

DPR did an in-depth analysis of a Sony A9 banding problem after Jared Polin found banding in his review of the A9. The article covered a lot of factors like sensor readout speed, mechanical shutter curtain speed, lighting flicker, etc. It's a good article to use as a reference.

What they found in this instance were LED lights flickering at over 7 kHz. I doubt our camera's "anti-flicker" setting is designed to handle stuff like this. So in addition to "mixed lighting", we photographers now have to be prepared to deal with "mixed frequency" situations.

 

[MCLV]

DPR did an in-depth analysis of a Sony A9 banding problem after Jared Polin found banding in his review of the A9. The article covered a lot of factors like sensor readout speed, mechanical shutter curtain speed, lighting flicker, etc. It's a good article to use as a reference.

What they found in this instance were LED lights flickering at over 7 kHz. I doubt our camera's "anti-flicker" setting is designed to handle stuff like this. So in addition to "mixed lighting", we photographers now have to be prepared to deal with "mixed frequency" situations.

That article overlooks aperture dependence of banding when mechanical shutter is used. See this thread for a demonstration https://www.dpreview.com/forums/post/65887363. Electronic shutter with single row readout and the same scan time as mechanical shutter still wouldn't produce the same results as using mechanical shutter.

 

[iljitsch]

LED lights flickering at over 7 kHz. I doubt our camera's "anti-flicker" setting is designed to handle stuff like this.

Not the Nikon Z fc:

Flicker reduction can detect flicker at 100 and 120 Hz (associated respectively with AC power supplies of 50 and 60 Hz). The desired results may not be achieved if the frequency of the power supply changes during burst photography.

I believe how this works is that the camera checks for flickering lights at these frequencies and if it finds flicker, it times the exposure such that it's done in sync with the light flicker so the entire frame gets exposed.

All flickering issues can be solved by sufficiently lowering the shutter speed. Sure, going to 1/20 because you're using the electronic shutter and the sensor readout is 1/20 is not always reasonably possible, but if the flicker is 1/7000 then I'd expect zero banding at 1/1000 and much reduced banding at 1/2000.