manofhg Loc: Knoxville, TN

Not sure what category to put this in, but this is more of a video question than picture taking. I was shooting indoors, documenting something for my church. I was shooting both pictures and video. I started noticing horizontal banding across the screen during the video shooting and once I got home, I could see that some of my pictures suffered the same fate. After researching the cause, I believe that it was caused by the shutter speed being too fast for the type of lighting due to 60 Hz, but maybe over 1/250 shutter speed. While looking at the specs for the photos affected/not affected, the slower shutter speeds (around 1/160 was fine) were generally okay while the high speed were pretty bad in some cases.

That answers my question for the pictures, but I'm still puzzled by why the video was affected. Since my video only records at 30 fps or that is how it is advertised, then I would have been at the very low end of shutter speed and based on the reasons stated above, I shouldn't have seen any affects. I do realize that the shutter does not actually move during the video shooting.

I've attached a picture that shows the banding I'm speaking of. It was a captured frame from a vid. The banding is always across the long length of the frame, therefore they are vertical if shooting in portrait.

(Download)

PHRubin Loc: Nashville TN USA

While frames are seperated by ~1/30 seconds, its duration is much shorter. In fact, fast enough to see the effects of 60 Hz blinking. The banding results from the fact that the frame rate is not syncronized to the line voltage rate.

bleirer

For stills you can turn on flicker detect on some cameras.

manofhg Loc: Knoxville, TN

Thanks for commenting.

I'm wondering though if when I set my stills to a slower shutter speed such that it fixes the stills, will the video be fixed as well. I'm thinking this because any settings I use for stills sets the levels for the video. Guess I'll have to try and see.

manofhg Loc: Knoxville, TN

Thanks, but don't think my camera has that. I use a 5D III.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

The solution also includes setting the proper capture frame rate.

https://www.fullexposure.photography/how-to-stop-camera-light-video-flicker/

I think you are correct - the 5D Mk III doesn't have an anti-flicker mode.

camerapapi Loc: Miami, Fl.

I am of no help regarding movies but if shooting JPEG images banding could easily be the result of working in 8 bits. Edit with 16 bits and you will not see banding again.

burkphoto Loc: High Point, NC

Banding can occur whenever the light source is cheap LED or fluorescent or sodium vapor or mercury vapor, powered by AC, and the shutter speed is faster than the line frequency of the power.

Video in the USA runs 24fps (for film productions recorded on video) or 30fps (there are more precise, fractional speeds for true video, but 24 and 30 are good enough for discussion here).

The usual and customary setting is what is called a "180 degree shutter angle." In the case of 30fps video, that equates to 1/60 second shutter speed. The idea is to get just a tad of motion blur that "joins" frames of moving subjects together, so movements don't look jerky or clipped, as if photographed under a disco strobe light.

The best advice I can give you is to use a shutter speed double the frame rate, up to the line frequency of the power. That should avoid MOST banding. However, if the building has cheap 277-volt fluorescent lights, powered from two phases of a three phase 480-volt feed, you most likely will see banding or slowly cycling color shifts in video, anyway.

manofhg Loc: Knoxville, TN

Thank you all those who responded. When shooting pictures, at 1/160 second shutter speed, I really didn't notice banding. When shooting faster, it became like the image above if I was very fast. I now know that the cause for the banding in the pictures, but if the video rate is 30 fps (or 24) should the video be affected when I change to a high shutter speed for pictures? If I do change the settings for pictures, the brightness for the video is changed as well or controlled, but I don't understand how if the frame rate is always 30. Maybe it is adjusting the aperture for when I make shutter speed changes. Outside or in natural light, it is fine since the light isn't constant. Incidentally, I was shooting in a gym so I think the lights are sodium or merc vapor.

burkphoto Loc: High Point, NC

See my answer above. Know also that the frame rate is controlled electronically, separately from the shutter. They are independent of each other. You can use 30 fps with 1/250 second (but you may not like the results).

Best let video be video and stills be stills.

You should not get banding in daylight or under quartz-halogen lamps (continuous light sources).

PHRubin Loc: Nashville TN USA

When you set stills to a lower speed (>1/60 sec) it gets a full cycle or more within the exposure. As I stated, with video although frames may be seperated by more than 1/60 sec, each frame is much less than the seperation time, or frames per second. So it only sees a part of the cycle per frame. I don't know what the exposure PER FRAME is when shooting video.

burkphoto Loc: High Point, NC

On a traditional "pro video" camera, the exposure time is called "shutter angle." The normal shutter angle is 180 degrees, which equates to a shutter speed of half the frame rate. Frame rate 24, shutter angle 180 is 1/48 second. Frame rate 25 (Euro-video), shutter angle 180 is 1/50 second. Frame rate 30 (USA...), shutter angle 180 is 1/60 second, and so forth.

The higher the frame rate, the less "cinematic" the effect (traditional film frame rate is 24.000 frames per second, with a true 180 degree shutter).

dSLR and MILC users with video can use faster shutter speeds (narrower shutter angles). The exposure is reduced, but the frame rate is the same. The electronics merely transfer the exposure they get to still photos at that rate. The EFFECT is jerky video, but video that is better for motion analysis. To a point, sports scenes look better with less inter-frame blur.

Some recent digital still cameras that record video give the user the option to set true shutter angles. The Lumix GH4 and GH5 can set shutter angles of 11 to 360 degrees. (At 360, the frame rate and shutter speed are the same.) What the camera is really doing is calculating an exposure time (shutter speed) that equals the shutter angle the user sets. It's an electronic simulation of the shutter in a film movie camera.

manofhg Loc: Knoxville, TN

Thanks again to each have just responded. I'll have to try out different shutter speeds for still when shooting vid to see the effect. I don't think that the 5DIII has the option for "true shutter angles" but I'll look into it. Also, I don't think it has much faster than 30 fps ability either. Since I'm now convinced by all the advice that it is a light type issue combined with shutter speed, I need to check it out in lights that I can see the effect in pics and vid, then slow the shutter speed and check the vids for how they respond.

TriX Loc: Raleigh, NC

An excellent explanation of a poorly understood subject. Thanks!

burkphoto Loc: High Point, NC

You’re welcome. Video with mirrorless is one of my interests. I have twins who are would-be filmmakers.