Toronto Photography Meetup Group

Hooray! 24fps support!

Canon EOS 5D Mark II: Statement on Firmware Development

London, 20 October 2009

Saw this, Quite exited.

since they're gonna take so long, i am hoping that they'll also add 720@60 as well.

I don't know much about video so...why would I want to shoot at 24fps if I can do 25. Isn't 25 better than 24?

There are three main frame rate standards in the TV and movie-making business.

60i (actually 59.94, or 60 x 1000/1001 to be more precise; 60 interlaced fields = 29.97 frames) is the standard video field rate per second that has been used for NTSC television since 1941, whether from a broadcast signal, rented DVD, or home camcorder. (When NTSC color was introduced, the older rate of 60 fields per second was reduced by a factor of 1000/1001 to avoid interference between the chroma subcarrier and the broadcast sound carrier.)

50i (50 interlaced fields = 25 frames) is the standard video field rate per second for PAL and SECAM television.

30p, or 30-frame progressive, is a noninterlaced format and produces video at 30 frames per second. Progressive (noninterlaced) scanning mimics a film camera's frame-by-frame image capture and gives clarity for high speed subjects and a cinematic-like appearance. Shooting in 30p mode offers video with no interlace artifacts. The widescreen film process Todd-AO used this frame rate in 1954

[quote="SamObeid"]There are three main frame rate standards in the TV and movie-making business.

60i (actually 59.94, or 60 x 1000/1001 to be more precise; 60 interlaced fields = 29.97 frames) is the standard video field rate per second that has been used for NTSC television since 1941, whether from a broadcast signal, rented DVD, or home camcorder. (When NTSC color was introduced, the older rate of 60 fields per second was reduced by a factor of 1000/1001 to avoid interference between the chroma subcarrier and the broadcast sound carrier.)

50i (50 interlaced fields = 25 frames) is the standard video field rate per second for PAL and SECAM television.

30p, or 30-frame progressive, is a noninterlaced format and produces video at 30 frames per second. Progressive (noninterlaced) scanning mimics a film camera's frame-by-frame image capture and gives clarity for high speed subjects and a cinematic-like appearance. Shooting in 30p mode offers video with no interlace artifacts. The widescreen film process Todd-AO used this frame rate in 1954

[quote="SamObeid"]There are three main frame rate standards in the TV and movie-making business.

60i (actually 59.94, or 60 x 1000/1001 to be more precise; 60 interlaced fields = 29.97 frames) is the standard video field rate per second that has been used for NTSC television since 1941, whether from a broadcast signal, rented DVD, or home camcorder. (When NTSC color was introduced, the older rate of 60 fields per second was reduced by a factor of 1000/1001 to avoid interference between the chroma subcarrier and the broadcast sound carrier.)

50i (50 interlaced fields = 25 frames) is the standard video field rate per second for PAL and SECAM television.

30p, or 30-frame progressive, is a noninterlaced format and produces video at 30 frames per second. Progressive (noninterlaced) scanning mimics a film camera's frame-by-frame image capture and gives clarity for high speed subjects and a cinematic-like appearance. Shooting in 30p mode offers video with no interlace artifacts. The widescreen film process Todd-AO used this frame rate in 1954

Via Youtube: Canon 7D test comparing 24p and 30p

24p http://www.youtube.com/watch?v=VoI6NVEpX_4
30p http://www.youtube.com/watch?v=e7wZwbXhhjc

You can see the difference when the cars drive by. The cars start to "lag" a bit with 24p.

There are many discussions about this online..
http://www.dvinfo.net/forum/jvc-gy-hd-s ... p-30p.html

http://forums.dvdoctor.net/showthread.php?t=41932

http://www.dvxuser.com/V6/archive/index ... 31546.html

Unless Canon made a horrific error, then no, there should not be a difference. Light travels at the same speed, frame rates are the same, etc. The only thing that I can think of that would create anything remotely close to a "sync speed" problem is the use of a different shutter speed. Changing the shutter speed with a video camera works similarly to still cameras. Main uses of a shutter speed change with a video camera helps with things like exposure, recording monitors, and more. This is referred to as a component called synchro scan. I can try to get into more details but I'm kinda lazy... Google is your best friend.

The problem arises when shooting with multiple cameras because different cameras do not have exactly the same clock rate. Take the example of a clapper, followed approximately 5 minutes (or so) later with a balloon popping. Say two cameras are recording these two events.

Camera 1 starts, rolls for 20s, sees the clapper at 0:0:20:12 (HH:MM:SS:FF), but camera 2 sees it at 0:0:23:01

say the ballon pops exactly 5.000 minutes later in real time.

Camera 1 may record the event at 0:5:20:12

but Camera 2 may record the event at 0:5:23:03, a few frames early or late

Trying to sync these different footages together in some editing program will be difficult.

This timecode drift is not consistent, may grow or shrink with time, but sync'ing different video clips can generally be a pain, especially with cams whose timecode generators are not accurate.

This has nothing to do with frame rates, nor shutter speeds.

If you want to know more, the appropriate search term is timecode sync or sync drift.

Professional camera setups have either an external timecode generator that ensures that all cameras maintain the same timecode for every frame shot, or cameras that can generate a timecode sync signal so frames are interchangeable from camera to camera, and editors get to live longer.

Incidentally, some modern clappers have timecode displays which are really useful for film shoots, because the film media cannot store digital info like timecode.

Hmm.. wow, thanks for the info! I never knew.

Mike -- that's exactly what I'm talking about (or trying to talk about). Thanks for the insightful response and search tips! Peace