movie studio 2023
movie of stage show but on stage LCD screens cause movie flicker on playback
i filmed a stage show but they used LCD for the backgrounds
now when we watch the video the screens have the bars scrolling so movie unwatchable
is there anything within the software that could cancel or correct this annoyance
thanks folks hope you can help
Brian
Hi Brian.
This is mainly an in camera problem where the frame rate is not the same or a division or multiple of the frequency controlling the lighting. In mixed lighting conditions sometimes this is unavoidable.
My cameras have anti flicker settings but can only be set to either 50 or 60Hz.
Once you have a problem like this there is no guaranteed method I know of that can entirely eliminate the problem.
You can try the following and it may need either fine tuning or may not work.
First hopefully all the footage is on one or the first two tracks of the timeline. 🤞 If the footage isn't on one or the first two tracks then the same trick will be relevant but it will be up to you to sort out the additional problems.
First First copy and paste the whole track/s and contents to another track/s (It's better if the sound and video are on separate tracks)
Then enlarge the time on the timeline and pull one set of objects on the pasted track back by one frame.
Mute the sound track of that selection.
Then using the Chroma key tool on the lower track try to blend the two tracks together. I would start by trying the Mix option and blend around the 50% mark. If that doesn't work then try Stamp at 100% blend and back it off. Then if those don't work try either the black or white options. Adjust sliders to best effect.
A still will look blurred but the video motion should not.
Sorry I don't have any appropriate footage to show the desired result.
What should happen is you will get a slightly blurrier video but with less flicker. When I say blurry I mean more akin to motion blur and not much of it. Ideally there should be a blend mode in the program with choices similar to those you get in photo editing programs rather than having to resort to using Chroma key but sometimes you have to try to work with what you have.
The idea being is while some frames are dimming the blended layer will not be and as the brighter the frames get the corresponding ones get darker and hopefully even them out.
It works better with blended layers but the Chroma Key effect may work. The other blend modes I haven't highlighted in the image above will not work.
Good luck.
Ray.
[Edit]
I should add. If the stage had mixed lighting, any type of incandescent lighting along with the LCD problem this may produce other problems instead.
Ray,
I think i will not get involved
a friend was asked to take stills of an amateur production in a theatre
his photos are excellent
but then they asked for video
this is not his area
he took the footage and its great till he pans round and the rear of the stage is a large lcd screen then it produces the power bars of the lcd
the guy did not get payed for his work it was a favor
i think to try and help him with the video would be a bit of a chore so on this occasion will just step back
your knowledge is amazing
i may now experiment with chroma key to get to grips with it
Thanks Ray
we are 50hz mains in uk
Hi Brian.
Large LCD screens were the bane of my my life when taking images for sports or event organisers. Quite often they are used to relay the event or give scores and are nearly always in view somewhere within a frame. It's a lot easier correcting stills than video when this type of thing goes wrong and nearly always easier to get right in camera than in post. LED stage lighting is another one depending on the dimming method. It's an easy mistake to make and we have all done it at some point. I can't say I blame you but sometimes it's fun to try.
[Edit]
Yes but the screens are often 60 Hz (If they are not large TVs) then you can't win easily.
Ray.
fab pics, great quality
I've posted here in the past about LCD lighting being a pain and I've used the technique Ray has suggested but in a slightly different way:-
I use 3 tracks of the video on tracks 1, 2 and 3 each 1 frame advanced (i ungroup tracks 2 and 3 and remove the audio) - track 3 in the original place, track 2 advanced 1 frame and track 1 advanced one frame further.
Then reduce the transparency of track 2 and 3 to around 50%
This will darken the final video so it's a good idea to increase the Gamma in track 1.
There is motion blurring as Ray said there would be but it's not too bad and the end result is a lot better than the original (please note my videoing prowess 😏)
Original
With the above technique
But of course the real answer is to use Neat Video - well worth the money in every respect.
AndyW
Hi Andy.
The use of Chroma Key is a fudge for MMS and VPX. Ideally you need a video editor that allows different blending modes on the overlaying track. Then Multiply or Overlay can work much better. Three overlapping tracks produces too much motion blur to be comfortable to view for me but that is very subjective and personal to the viewer.
Ray.
@CubeAce Agreed but it's free and it is an improvment whether two tracks or three.
Just been playing and I've come across something I don't understand. It works to a degree in that it's an improvement in reducing flicker/scrolling and it only seems to work if the original video is interlaced.
If your file it is interlaced, right click on the video in the timeline and select properties. Open the video tab and under "Intermediate Images" change it to "Full Frame (non-interlaced)"
I'd be interested if others can try it and see a slight(ish) improvement or if it's just my imagination.
AndyW
@spuddy13, @CubeAce, @me_again
Hi
. . . . I think i will not get involved . . . .
I am of the same mind if the strobing is bad enough that Neat Video cannot fix it. Neat Video can do a very good job, however it is not a 'cure all'.
There is another related issue that is rarely discussed, and should be taken in to account when presenting video having this strobing issue and that is the viewing audience, in particular anyone who suffers from Photosensitive epilepsy.
Any viewer who suffers from PE may be affected by the flickering/strobing in the video, AndyW's original clip above is a good example of strobing.
. . . . screens are often 60 Hz .... then you can't win easily . . . .
Very true unless the camera shutter is locked to the screen refresh clock, see this blog, which is one of many on this issue, for ways to minimse this issue.
John EB
this has been interesting topic
great discussion
i think if it was my own footage i would take it further
but i don't possess the footage its a friends
i wanted to help but on this occasion i remain silent
thanks folks
the knowledge in this forum is amazing
B
@johnebaker @me_again @spuddy13
Hi John.
In the instance of my comment on the refresh rate of a screen of LED bulbs on a dimmer, sometimes, depending on the type of dimmer and when mixed with an incandescent light source of a different fixed frequency, then often, one of the two of them will cause flickering to a greater or lesser degree. That is what I meant by a situation you can't win easily. I have found with some modern power LED stage lighting that video will go in and out of strobing as various coloured spot lights go up and down in in strength and frequency. Often on opposing sides of an artists body on a stage. One place that has this really under control is Harry Potters world. Their lighting system is on another level and very camera (video or still) friendly. Then again, a place that is primarily a film studio should get that correct. I'm hoping over time and such tech gets better, cheaper and more widely available as frequencies of such lighting and screens rise, that eventually all of these problems will be a thing of the past.
Looking at the latest DJI camera sensors and processing techniques, noise in low light is already almost a thing of the past.
Ray.
Hi Ray
. . . . of a screen of LED bulbs on a dimmer, sometimes, depending on the type of dimmer and when mixed with an incandescent light source of a different fixed frequency, then often, one of the two of them will cause flickering to a greater or lesser degree. . . .
I was referring to Brian's issue which is LCD Screens.
With dimmer controlled domestic and non-video stage LED lamps the situation is worst with those that are driven at the mains frequency
LED lights for video use are different and do not 'flicker' when dimmed, they are usually driven at high frequency, eg 10 kHz - 20 kHz or more.
. . . . the latest DJI camera sensors and processing techniques, noise in low light is already almost a thing of the past. . . . .
They do appear to have cracked that one. I have been looking at the Action 4, it is impressive, not upgrading, yet, I am quite happy with the Action 3.
John