Frame per Second - banding

dancook said:
I don't know, there's all sorts, general light bulbs and spotlights setup by organiser. The odd candle :)
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I wondered if there was a light that cycyled its frequency and your frame rate needed to be low enough to catch an entire cycle per frame? Just a thought
 
boyfalldown said:
I wondered if there was a light that cycyled its frequency and your frame rate needed to be low enough to catch an entire cycle per frame? Just a thought
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Well as mentioned in OP, I was on 24 fps for the video above,

I believe lights are typically either 50/60hz - so my 30fps and 120fps did not cure it.

I'm thinking if I shot 25fps, it would be in sync for 50hz - other than trying it out next time I go, it's just guessing on my part
 
For most lighting, you don't need to capture an entire sinewave of the mains, just the same amount in each frame. So try 25p/50p in 50Hz regions and 29.97p/59.94p in 60Hz regions.

However, with that sort of flicker you'd expect the entire lit part of the image to change. Yours looks like interference between 2 lights or perhaps an electronic ballast causing a beat frequency with the camera.
 
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I think this is caused by LED stage lighting being out of sync with ambient lighting. You might find that it's not possible to get rid of it entirely with you shutter speed selection. You may have to sync you shutter speed with the stage lighting and then turn of some of the other ambient light sources to get rid of it.
 
ah5168 said:
I think this is caused by LED stage lighting being out of sync with ambient lighting. You might find that it's not possible to get rid of it entirely with you shutter speed selection. You may have to sync you shutter speed with the stage lighting and then turn of some of the other ambient light sources to get rid of it.
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Does my shutter speed affect the video then? I thought maybe it would just take on the FPS of the video, and ignore the shutter speed.

the options have been updated in a firmware probably, but here's some similar look to what I See

View attachment 109185
 
Shutter speed does affect video, as a general statement, but it depends on whether it's configurable with the camera in question. It's usually referred to as degrees in videography, with 180 degrees meaning the shutter is open for half the length of each frame. e.g. with 30 frames a second, and a 180 degree shutter angle, the shutter is open for ((1 second / 30) / 2).

Shutter angle / shutter speed during video defines how much movement blur there is in each frame of the video, leading to more or less natural feeling of movement.

NB: I'm not a videographer, everything above is probably a hatchet job.
 
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You need to sync the opening and closing on the shutter with the strobing of mains powered lights. In theory multiples of of 50 should give you this 1/50s, 1/100s but you sometimes get better results as 1/60th multiples. Just experiment and see which gives the best result. General rule of thumb is that the shutter speed should be double the fps but with an DLSR you are not tied to this you can shoot 25 fps and 1/25s second if you wanted just try some options to get the look you want.

I should mention that you may get some frame to frame changes in brightness if the shutter speed and frame rate don't relate to the mains frequency. So if you went for say 25 fps and 1/40s shutter speed you might get some variations in brightness.
 
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when i use my nikon d500 in 4k video mode no problems no matter what the lighting conditions this model has a flicker detection to help combat light flicker
does your camera not have anything like that ?
maybe you camera video is not up to hard light conditions
read the manual see if there are any pointers in it
 
holty said:
when i use my nikon d500 in 4k video mode no problems no matter what the lighting conditions this model has a flicker detection to help combat light flicker
does your camera not have anything like that ?
maybe you camera video is not up to hard light conditions
read the manual see if there are any pointers in it
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No, and the manual doesn't tell me more than I'm already figuring out.

With the Leica SL, you have a choice between a wide variety of resolution settings including two different 4K resolutions (4096 x 2160, often referred to as 'cinema 4K', and 3840 x 2160, the resolution used in UHD television sets). Except for 4096 x 2180, which is only available with a frame rate of 24fps, all other resolutions can be combined with different frame rates. This allows them to be matched e.g. to the prevailing mains frequencies, or to ensure especially smooth rendition of moving subjects with the higher frame rates. All frame rates are of the progressive type.

MP4 MOV 4096 x 2160 /24p 4096 x 2160 /24p 3840 x 2160/30p 3840 x 2160/30p 3840 x 2160/25p 3840 x 2160/25p 1920 x 1080/120p - 1920 x 1080/100p - 1920 x 1080/60p 1920 x 1080/60p 1920 x 1080/50p 1920 x 1080/50p 1920 x 1080/30p 1920 x 1080/30p 1920 x 1080/25p 1920 x 1080/25p 1920 x 1080/24p 1920 x 1080/24p 1280 x 720/120p - 1280 x 720/100p - 1280 x 720/60p 1280 x 720/60p 1280 x 720/50p 1280 x 720/50p 1280 x 720/30p 1280 x 720/30p 1280 x 720/25p 1280 x 720/25p 1280 x 720/24p 1280 x 720/24p
 
Can you remember or tell from you metadata what the shutter speed was set to.
 
Looks like the 1/160th may have been the problem then. Might be better to pick 25 or 50 fps then use shutter speed priority to maintain 1/50s or 1/100s respectively if you still get some banding try 30 fps and 1/60s, if still doesn't solve the problem go back to your first settings and try turning off some of the light sources.
 
Could always try setting to AE.

Also ProDad's ProDrenalin program may help in cleaning the banding from the existing vid.
 
ah5168 said:
Looks like the 1/160th may have been the problem then. Might be better to pick 25 or 50 fps then use shutter speed priority to maintain 1/50s or 1/100s respectively if you still get some banding try 30 fps and 1/60s, if still doesn't solve the problem go back to your first settings and try turning off some of the light sources.
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Can't turn off light sources and can't use shutter priority. But I am using manual, so that's fine.

Also think I need to change the shutter steps as from memory not sure 50 and 100 appear!
 
Yes you should have shot at 25fps if the lighting is something standard and you don't have any control over it. This is to match the 50hz of UK electricity
 
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