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Subject:RE: 24p
Posted by: risce1
Date:5/28/2016 9:30:22 AM

What happens if you pan or someone moves quickly...not that fast movement is part of most church services I have seen...but still, would think you have herky jerky like crazy and that is not fixable

Subject:RE: 24p
Reply by: DonaldT
Date:5/28/2016 9:34:27 AM

Pull down is not related to shutter speed, it is frame rate. DVD specs were designed during the analog video world and had to adhere to NTSC or PAL standards. NTSC standard is 29.97, but film makers wanted to keep their film at 24fps. This allowed them to get better quality compression since there weren't as many frames to compress and then the DVD player adds the pulldown during playback. The flag alerts the player of the frame rate and pull down order.

Subject:RE: 24p
Reply by: risce1
Date:5/28/2016 11:25:43 AM

you tested and found what works for your situation, you bet understand compromise, I do it all the time!

Subject:RE: 24p
Reply by: Serena Steuart
Date:5/29/2016 8:11:19 PM

To answer your question on "why 1/48 sec shutter?", the convention goes back to film.
Film cameras moved the film intermittently through the gate, the film being stationary during the exposure and blanked by a shutter while it was being moved for the next frame exposure. In general the cameras used a rotating disk for the shutter, the open sector being half (180 deg) of the disk. So at 24fps this gave 1/48 sec exposure for each frame. And, of course, always an exposure of half the frame rate. Many cameras could vary the open sector of the shutter, so 1/48 sec at 24fps was not invariant. Of course no camera could have a 360 deg open sector, as you can in video, and as you are using. Film shot using a small shutter opening would look very jerky because each frame would be sharp without any motion blur to merge the action from one frame to the next.
On your camera you may be able to select shutter angle instead of exposure time (old hands are happier with shutter angle) and then you would set 180deg to get 1/48 sec and 360 deg to get 1/24sec.

Message last edited on5/29/2016 8:15:02 PM bySerena Steuart.
Subject:RE: 24p
Reply by: DonaldT
Date:5/29/2016 11:41:42 PM

Well, for that matter, 24p is a convention for film as well. :)

Subject:RE: 24p
Reply by: Kinvermark
Date:5/29/2016 11:45:40 PM

"And we know that video is not film, so the convention for film should not apply to video."

Does your video camera use a lens and shutter? Then it applies!

I would agree that this isn't a technical necessity, however, just an aesthetic one, and thus totally subjective.

Subject:RE: 24p
Reply by: Serena Steuart
Date:6/1/2016 12:27:36 AM

Vidmus, I'm surprised at your hostility. You asked a question and you got the answer. Whether film or video you are representing the world through a series of still images. If you have read up on how we actually perceive the scene around us you will know that our brains are subjectively creating a great deal from the scant information our eyes actually transmit moment by moment. So it isn't too surprising that people make different subjective conclusions about how best to represent the 'real' world via video. People are used to the artificial world created at 24fps in theatres and 1/48 sec exposure per frame is part of that illusion; that is the only reason for using it now. Other people are more used to the illusion of 60 fields per second. You could have seen in my answer to you that using a 360 deg shutter can create favourable motion blur, in addition to giving you an extra stop. But I guess hostility closed your window of comprehension.

Subject:RE: 24p
Reply by: VidMus
Date:6/1/2016 11:36:45 AM

@ Serena Steuart

I sincerely apologize for coming across as being hostile. I did/do not want to do that. Looking at my post I can see that my choice of words were not the best considering you can only read what I post and not hear how I am actually saying it.

This is part of the limitations of text only and not hearing how I am actually expressing it.

I will try to do a better job with my wording in the future.

Because of my very poor speech hearing, I very seldom communicate with others. So I do not do very well with communications anymore.

Peace,

www.dannyfye.com

Subject:RE: 24p
Reply by: Serena Steuart
Date:6/1/2016 7:50:10 PM

Fine.

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