HVX 200 Panasonic 720HD Help

[KarimV]

Hey,

I'm having an issue when I exported my footage from my camera to FCP. Accidentally the fps came out 60, however I need it to be at 30. The only way I know of changing it is in Quicktime when I export it into another Quicktime Movie, however I heard this may hurt my footage. Is there another way of changing the fps rate?


Thanks

[Gravy]

Just change it on export as you suggested. It shouldn't effect quality; should just drop every other frame.

Try it yourself and see if you can notice the quality difference. That's the only test that matters really.

[Athiril]

If you dont have complex opposing motion where youd need to get in and do masking, I would recommend giving Twixtor a go if you can get a hold of it, perhaps you can do some speed retiming in Motion, I heard that may work half as well as Twixtor too, so that may be worth a shot.

Cutting out every other frame you're going to get 1/2 the shutter angle you shot at in terms of motion blur, so if it was 180 it now will be 90, frame blending will net you your shutter angle you shot at but with other artifact.. which is if you shot at 180 degree, you'll get 90 degree on then off, then on again for 90 degrees, and off again for 1 frame.

That is, some motion blur, a sudden gap and then some more motion blur (object has jumped across the frame in motion blur) for a single frame.

Personally I would live with the 1/2 shutter angle.

[Gravy]

Cutting out every other frame you're going to get 1/2 the shutter angle you shot at in terms of motion blur, so if it was 180 it now will be 90, frame blending will net you your shutter angle you shot at but with other artifact.. which is if you shot at 180 degree, you'll get 90 degree on then off, then on again for 90 degrees, and off again for 1 frame.

Personally I would live with the 1/2 shutter angle.

No it won't. You can't change the shutter angle it's "baked" in to each frame. If he shot at 60fps with a half frame exposure (180 degree, 1/120th) each frame is still going to have a half frame exposure. It will always look smoother though due to the fact it's at 60p the exposure time will of been half of what it would of been at 30p (1/60th).

So if he wanted to shoot at 30 p he's already at a 90 degree shutter. Nothing can be done about it. Unless want to go through CPU intensive motionblur creation.

[Athiril]

"Cutting out every other frame you're going to get 1/2 the shutter angle you shot at in terms of motion blur"


No it won't.

Yes it will, you are wrong.

Cutting out half the frames and you throw away half the motion information, it'd be the same as shooting 30p 90 degree.

[donaldStrubler]

Have you looked into the DVCPRO HD Frame Rate Converter?

Its under Tools > DVCPRO HD Frame Rate Converter.

Thats what I've always used for 60-30 or vice versa

[Gravy]

Yes it will, you are wrong.

Cutting out half the frames and you throw away half the motion information, it'd be the same as shooting 30p 90 degree.

Seriously think about it. You can't get rid of motion blur, the motion blur in each frame is still there. It might make it a bit more steppy (so it will look more like a faster shutter in that aspect). But, the same amount of motion blur is there in each frame.

This is why for example the 5D can never look like 24p even if you change the frame rate. The motion blur just isn't there.

If I can find some time (which is unlikely) I'll get my camera out and shoot some tests.

[Athiril]

Err, shooting at 50p/180 = 1/100th of a second shutter speed.

Shutter speed cant be changed, shutter angle varies with frame rate, it will remain at 1/100th of a second, cutting out every second frame, gives you the same results as 25p 1/100th of a second shutter, which is 90 degrees, the motion blur per frame will be the same in both, not per time interval.

The same shutter angle is used for getting the same motion blur between different frame rates.

360 / shutter speed * frame rate = shutter angle.

http://i32.tinypic.com/15nkrbq.png

And 5D footage will look just like 24 fps if you change it to 24 fps, 24fps is 24fps, 180 degree shutter angle is just the 'default' for general shooting, a starting point, if you cut out every 6th frame and want 180 degrees, you need to shoot at 1/48th, closet being 1/50th, though then you miss an uneven segment in time (not a prob for cutting every 2nd frame, thats even), retiming with twixtor would be something different.