GH13 Wedding flash photography & florescent flicker

T

tipdrinker

Member
Hi,

I've just started out doing some wedding videos with my gh1 (since hacked) that I got with a kit lens for $350 and I have noticed some issues.

One is that when I was filming in the church I had black bands across the frames. It's caused by the archaic florescent lights. Everywhere I read it's said to make sure the shutter speed is set to 50 but my camera was so I'm not sure what to do. Is there a way of removing it in post in premier cs5?

Also in some parts of the wedding where there is a lot of flash photography at the cutting of the cake, first dance etc and when a flash goes off it seems to light up half of the frame while the other half is unaffected which looks quite ugly. does anyone know how to fix this in future when i'm filming? Should I drop the shutter speed to 25 or increase it?

Cheers, would appreciate the help as I've another wedding in a month :)

You can see the flash problem on my first wedding highlights video at around the 40 second mark.

 
As far as the camera flashes, welcome to world of DSLR. That is the result of rolling shutter, where your camera processes the information by scanning across the frame. Traditional video cameras use a global shutter where all of the information is captured at once. It's simply a limitation to cope with for now. I actually don't mind the flashes, and I think it's just one of those things that you get accustomed to over time.

As to the fluorescents, I'm not sure - but maybe someone else can chime in. The video looks very nice BTW!
 
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Thanks for the compliment. That's grand re rolling shutter. As long as I'm not doing something wrong :) still puzzled regarding the fluorescents. BTW I just uploaded the wedding I was on about...

 
tipdrinker said:
One is that when I was filming in the church I had black bands across the frames. It's caused by the archaic florescent lights. Everywhere I read it's said to make sure the shutter speed is set to 50 but my camera was so I'm not sure what to do. Is there a way of removing it in post in premier cs5?
Click to expand...

What you have to do with fluorescent lighting is to make sure that you expose each frame at the same place in the power cycle. In other words, in a 50Hz country, you expose at 1/50 second. In a 60Hz country, you expose at 1/60 second. Or some even multiple. So in a 60Hz country, you could use 1/120, 1/60, 1/30, etc. The major symptom of a mismatch is the dark bands. So I'm guessing you were in a 60Hz country shooting at 1/50th, which won't do well because each frame will be exposed during a different part of the power cycle.

Can you remove this in post? If you are willing to work each frame individually, you can perhaps do some fancy masking and levels matching, but it's very slow and very labor intensive. I don't know of any automatic way to do this. But just because I don't know of a way doesn't mean there's not one. Just sayin'.
 
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