View Full Version : 1/50 in 25p


Jon Turner
March 28th, 2005, 05:12 PM
i have read that you get closer to a 'film look' when shooting in 1/50 shutter speed in 25 progressive, as this emulates a film camera shooting 48 in 24fps.

my question is, why does a warning light come on the xl2 when you shoot in anything but 1/25 during 25p mode? this would suggest that canon recommends shooting in 1/25 in 25p.

why should this be the case? are we somehow bucking the system by shooting 1/50?! or can using the wrong shutter speed cause genuine problems in post? or is it that for most videographers the motion blur characteristic of film is not something they want to emulate in the first place?!

what is it, fellas?!

Chris Hurd
March 28th, 2005, 05:34 PM
Howdy from Texas, Jon,

<< why does a warning light come on the xl2 when you shoot in anything but 1/25 during 25p mode >>

Don't think of it as a warning light. It's simply an indicator that you're operating outside of the usual default mode. The light is telling you, "just so you know, as a friendly reminder, we're in a special situation here."

I just wish those viewfinder lights could be custom configured to what I would like then to be. Now that would be handy!

Richard Hunter
March 28th, 2005, 10:03 PM
Jon, I think it's just a mistake. Canon have set the default shutter in 25p to 1/25s, and this is wrong because it is too slow for any photography where there is movement. The corresponding shutter speed for 24p is 1/48s, and it does not make any sense that there should be such a big difference in shutter speed when you go from 24p to 25p.

Chris, this is not just an issue with the viewfinder light setting. When you switch modes on the camera, selecting 25p often causes the shutter speed to default to 1/25s. If you don't notice and correct it, you can end up with unusable video.

Richard

Jon Turner
March 29th, 2005, 05:08 AM
but why is 1/25 the default setting? presumably canon thinks this is the optimum setting? and yet everyone i've communicated with says the same - that 1/50 is the the way to go in 25p mode.

Richard Hunter
March 29th, 2005, 06:30 AM
<<<-- Originally posted by Jon Turner : but why is 1/25 the default setting? presumably canon thinks this is the optimum setting? -->>>

Or maybe they just made a mistake? That's what I think anyway.

Richard

Jon Turner
March 29th, 2005, 08:13 AM
richard, it's almost as if you're saying canon are fallible, or something... ! ;-)

ok thanks for your comments!

Richard Hunter
March 29th, 2005, 12:48 PM
Nooooooooooo! Where did you get that idea from? :)

Richard

Geoffrey Engelbrecht
March 29th, 2005, 01:50 PM
This 1/50 sec setting is just to emulate the appearance of a film camera.

Why should a setting to emulate a film camera be the "correct" default? The XL2 is after all a video camera ... isn't it? ;-)

If I understand correctly when you shoot at 1/25 sec with 25 fps then you should have no delay between between the shutter and capture. Motion is blurred but there is no strobing of the image. When you shoot at faster shutter speeds then there is strobing of the image because there is a delay between when the shutter closes and the next frame is taken.

Therefore it makes a lot of sense to me that 1/25 sec is the default for 25 fps. But then I'm shooting video and not film. :-)

Marty Hudzik
March 29th, 2005, 02:57 PM
<<<-- Originally posted by Geoffrey Engelbrecht : This 1/50 sec setting is just to emulate the appearance of a film camera.

Why should a setting to emulate a film camera be the "correct" default? The XL2 is after all a video camera ... isn't it? ;-)

If I understand correctly when you shoot at 1/25 sec with 25 fps then you should have no delay between between the shutter and capture. Motion is blurred but there is no strobing of the image. When you shoot at faster shutter speeds then there is strobing of the image because there is a delay between when the shutter closes and the next frame is taken.

Therefore it makes a lot of sense to me that 1/25 sec is the default for 25 fps. But then I'm shooting video and not film. :-) -->>>

If that was true then shoudn't the XL2 in NTSC have a default of 1/24 instead of 1/48? At the bare minimun there seems to be some inconsistency between the 2 regions.

Geoffrey Engelbrecht
March 29th, 2005, 03:55 PM
What is the default shutter speed for 30 fps on the NTSC model?

24 fps on the NTSC model is not exactly the same as 25 fps on the PAL model. 24 fps is specifically aimed at people trying to simulate film hence the default you suggest makes sense also. 25 fps can be used for this but also for standard progressive video which I would assume 30 fps is a better option for in NTSC land.

Don't miss my meaning about truths. I'm just challenging the belief that the default should be the simulation of film. I figure it is a personal esthetic choice what shutter speed to choose.

But I can understand the logic given the default for interlaced video is 1/50th sec that for progressive video where each full image is recorded half as frequently that the shutter speed be half as fast.

Richard Hunter
March 30th, 2005, 10:13 AM
Hi Geoffrey. The big problem with 1/25s is what you say already - motion is blurred. I tried shooting with the camera on this setting when I first got it, and the results were unusable whenever there was any movement. I agree that shutter speed is a personal choice, but I can't imagine enough people preferring to choose 1/25s that it should be the default for PAL cameras in 25p mode.

Richard