How to fine tune high speed frame rate/shutter speed to avoid flicker on FS700?

[ebsseattle]

I use the S&Q motion setting from time to time, but haven't yet figured out how to fine tune all the controls when in the S&Q mode. I prefer to shoot with 240 frames per second, but to avoid flicker when shooting under fluorescent lights I would need to have the shutter speed at 1/60 second (or 1/50 second if in Europe). So why do I sometimes get some flicker and other times I don't? I've tried bumping the shooting speed down to 120 frames per second and that seems to fix it a lot. Is there some correlation between the 240 frame per second shooting, the shutter speed, and the lights that i'm not understanding?

As far as fine tuning, it also seems like when I enter S&Q motion mode, I'm no longer able to change the shutter speed. Sometimes it stays set where I left it before entering S&Q and other times goes to something else.

Any help is appreciated!

 

[Kyron]

Not all lights are created equal I'm afraid and flourescent lights are a complete no go for high frame rate recordings.

This article is a great read on the ins and outs of lights and high frame rate recordings and should answer most of your questions about why they flicker.
http://www.personal-view.com/talks/discussion/comment/80562

In S&Q motion you can still change the shutter speed, but you can't make it lower than the frame rate chosen.
Just make sure you're in manual mode, hit the shutter speed button on the left of the camera and shutter speed will highlight on the screen and is changeable with the up and down arrows.

The only options at 240fps is to choose a light source that is flicker free and not at the mercy of alternating current.

 

[John Foundas]

I have found that simply speeding up the 240 footage in the timeline by a few % points will solve most flicker frequency issues.
(480 probably not)
I gives me more confidence knowing that there is a fix if there is an issue. Doing "run and gun" I dont have a lot of time to check the index files after each shot. The buffering time is enough to deal with when things are moving.

 

[ebsseattle]

Not all lights are created equal I'm afraid and flourescent lights are a complete no go for high frame rate recordings.

...

The only options at 240fps is to choose a light source that is flicker free and not at the mercy of alternating current.

That's what I was afraid of. I'll check out the and play around with settings some more but was hoping to find some tricks that would help me avoid these issues from the get-go. It sounds like aside form changing the way fluorescent lights work on a worldwide scale, I'm out of luck.

 

[ebsseattle]

I have found that simply speeding up the 240 footage in the timeline by a few % points will solve most flicker frequency issues.
(480 probably not)
I gives me more confidence knowing that there is a fix if there is an issue. Doing "run and gun" I dont have a lot of time to check the index files after each shot. The buffering time is enough to deal with when things are moving.

That's how I've been dealing with it, a lot of times having to go up to even double speed (or down to 120 fps), but I'm trying to figure out how to capture nice shots in artificial, uncontrolled (i.e. non-professional) lighting, at 240 fps. Sometime 120 just isn't enough when I know 240 is possible.

 

[mainstreetprod]

I have found that simply speeding up the 240 footage in the timeline by a few % points will solve most flicker frequency issues.
(480 probably not)
I gives me more confidence knowing that there is a fix if there is an issue. Doing "run and gun" I dont have a lot of time to check the index files after each shot. The buffering time is enough to deal with when things are moving.

Thanks for that tip- the very first scene in my feature is industrial equipment under fluorescent lighting, and it had a bad flicker. Even though shot at 24fps, when I sped it up 5%, the flicker was reduced to almost nothing. No idea why this works.

 

[John Foundas]

Thanks for that tip- the very first scene in my feature is industrial equipment under fluorescent lighting, and it had a bad flicker. Even though shot at 24fps, when I sped it up 5%, the flicker was reduced to almost nothing. No idea why this works.

(thumbs up)