Need Help In Regards to 24P

[BDery2906]

Hey there.  Need some serious education here please.

 

First of all, I own and shoot with a JVC GY-HM700u.  Has a Fujinon 17x lens.  I love this camera. I have been shooting video for a long time.  I come from a news background with a huge love for film.  

 

I do mini documentary production with inspirational topics.  I shot my first short last year and did it in 24p.  I loved the look.  That infamous "film look".  However some images were jittery.  Come to find out, it's called the "strobe look".  I had the camera set to 24p.  Shutter set to 1/48.  Most of my shots were static and I don't even think I did any pans.

 

So what did I do wrong?

 

I did some tests with the same camera, shot a mock interview with some kino lights.  And the motion around the lips was real jittery.  I have been told that may because of the lights flickering at a speed that the camera with the frame rate, it got picked up.  I have an arri kit and haven't tested it with those yet.

 

It has to be some obvious thing I am doing wrong.  I have seen so many video clips with the same camera shooting in 24p and it looks so dang good and natural.

 

I shot my last educational documentary in 60p and it looks beautiful.  But its that HD video look and when I go to shoot my next project I want this 24p problem solved.  

 

Hope anyone can help and point this guy in the right direction.

[mcrockett]

Is it video coming right out of your camera where you're noticing the issue, or is it after you edit and render the new video?

[BDery2906]

Both.  I see the flicker in the viewfinder and the LCD viewfinder.

[mcrockett]

Hard to say. What happens if you boost your shutter speed, understanding of course that you may have to raise your ISO, but just as an experiment?

[BDery2906]

I'm not shooting on a DSLR.  I boosted the shutter up to 1/60 and still got the flicker.

 

[rs170a]

I have a 700 as well but have never gotten into the 2p "look" so I do all my shooting in 60i.

There is a forum dedicated to this and a few other JVC cameras so I suggest posting your question there. I've done so a few times and the folks there are very helpful.

http://www.dvinfo.net/forum/jvc-gy-hm-600-700-800-series-camera-systems/

 

Mike

[Aviv Vana]

Perhaps you are in the UK and 25p (instead of 24p)is your way to go? Light frequencies are different there. I'm no expert on this topic but it's worth a try.

[BDery2906]

I'm not in the UK.  I'm in the US.  

[onehorn]

Electric current in the U.S. runs at 60 cycles per second. Florescent lights are notorious for causing flicker (and also audio hum from time to time)  The flicker effect is easily noticeable if shooting a CRT TV screen or a computer monitor. It will look as if the TV screen is slowly rolling even though in reality it is not.

 

It can be very difficult to adjust shutter speed to match the lighting flicker, especially if you are after a specifc look.

 

Sometimes shooting at 50i or 60 i will eliminate the issue. You can still convert to 24p later using the 2-3 pull down method.

 

Or you use your own lighting to help aleviate the issue.

 

[dcasler]

I shoot training videos at 1080 60i AVCHD and render at 1080 24p H.264 (M2TS) and get good results. You might check your editing suite to see if it has a "motion blur" effect or similar. It interpolates between the "strobe" pictures and adds some blur in the direction of the difference between the two shots and might help smooth things out without a loss of clarity.

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