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-   -   S5 horizontal bar issue (https://www.dvinfo.net/forum/panasonic-lumix-s-g-gf-gh-gx-series/538470-s5-horizontal-bar-issue.html)

Bill Parker December 14th, 2021 04:04 PM

S5 horizontal bar issue
 
Hi. My S5 has developed a problem with a horizontal bar that rolls up the screen. It's a dark band. I've switched lenses, reset the camera, swapped batteries, turned off the lights - nothing seems to work. I even recorded it to see if it went through to the recording and it did. Has anyone else had this issue or have ideas how I might address it? thx

Rainer Listing December 15th, 2021 04:37 PM

Re: S5 horizontal bar issue
 
No takers? Hoping I'm wrong, but my guess is it's something serious, like needing a major electronics fix. Also hope your warranty is still active. I also have an S5, so I'm interested to see any other suggestions and how you get on.

Pete Cofrancesco December 15th, 2021 04:55 PM

Re: S5 horizontal bar issue
 
Rolling bars are often caused by led lighting that pulses. If the camera sensor read out is slow it shows up as rolling bars.

Bill Parker December 15th, 2021 09:35 PM

Re: S5 horizontal bar issue
 
That's exactly what it was. I just lowered the shutter speed and it went away. Never seen that before. that video was really helpful. Thanks!

Rainer Listing December 16th, 2021 02:02 AM

Re: S5 horizontal bar issue
 
That was going to be my suggestion but you said you'd turned off the lights. Glad you got it solved.

Christopher Young December 17th, 2021 07:15 PM

Re: S5 horizontal bar issue
 
Quote:

Originally Posted by Bill Parker (Post 1966682)
That's exactly what it was. I just lowered the shutter speed and it went away. Never seen that before. that video was really helpful. Thanks!

Basically, if you stick to a shutter speed that matches your power line frequency, 60Hz in the US and 50Hz in most PAL countries which respectively are 60th and 50th of a second or multiples of those like 120th and 100th you shouldn't see those issues. High-frequency lighting can also cause those issues. I've filmed a lot on navy warships and a lot of them run a 400Hz electrical system. This can cause a nasty flicker. If your camera has a function like ClearScan, found on some Sony cameras but also on other brands but under different names, you can incrementally dial in a shutter speed to sync the shutter rate to the lighting frequency.

Another good point to keep in mind is that if you are shooting for a 60Hz production in a 50Hz country bump your shutter speed to 100th as this is a multiple of 50 and you will eliminate the 10Hz frequency flicker that can plague your vision if shot with an off-speed shutter. Conversely shoot at a 60th in 60Hz countries if your production has to be a 25 or 50p production.

Chris Young

Pete Cofrancesco December 18th, 2021 10:26 AM

Re: S5 horizontal bar issue
 
Quote:

Originally Posted by Christopher Young (Post 1966692)
Basically, if you stick to a shutter speed that matches your power line frequency, 60Hz in the US and 50Hz in most PAL countries which respectively are 60th and 50th of a second or multiples of those like 120th and 100th you shouldn't see those issues. High-frequency lighting can also cause those issues. I've filmed a lot on navy warships and a lot of them run a 400Hz electrical system. This can cause a nasty flicker. If your camera has a function like ClearScan, found on some Sony cameras but also on other brands but under different names, you can incrementally dial in a shutter speed to sync the shutter rate to the lighting frequency.

Another good point to keep in mind is that if you are shooting for a 60Hz production in a 50Hz country bump your shutter speed to 100th as this is a multiple of 50 and you will eliminate the 10Hz frequency flicker that can plague your vision if shot with an off-speed shutter. Conversely shoot at a 60th in 60Hz countries if your production has to be a 25 or 50p production.

Chris Young

The issue has less to do with the frequency of the electricity. In my experience it due to inexpensive led lighting. When these lights are dimmed the banding becomes worse. I don't understand completely the mechanics of it and even if you did under certain type of lighting there is very little you can do to fix it. If you're filming an event such as a theater performance or wedding reception it's not an option to light the scene with your lights. If the banding is really bad I've found reducing the shutter speed only changes the rate at which the bars roll. Generally full frame sensors are more susceptible because it takes longer to read out the sensor.

Christopher Young December 19th, 2021 02:57 AM

Re: S5 horizontal bar issue
 
1 Attachment(s)
If the rolling bar interference is due to off frequency LEDs causing the issue, which is often the case with a lot of the nasty cheap LEDs that venues are re-equipping themselves with, is to use cameras with variable scan shutters. Something we have had to do frequently with broadcast cameras for years, since the '80s. Variable frequency shutters. It's the only way around the issue. Though that solution still falls down in venues where they have a couple of different frequency LED frequencies running simultaneously. You can dial one frequency out but not both together. In most situations with single frequencies, I find the answer in mirrorless cameras today is to use a Sony or similar that has a variable scan shutter that can increment up or down in 0.1 Hz steps. Sync the shutter speed with the lighting frequency and your problem goes away.


Chris Young

Example of a variable speed shutter setting on a current Sony a7 series camera is below.

Pete Cofrancesco December 19th, 2021 02:11 PM

Re: S5 horizontal bar issue
 
Agreed having a camera that has variable shutter and knowing how to access and change those settings is vital if you do a lot of live venue work. Because these bars are near impossible to fix in post.


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