2008-06-10

PF25 vs. 50i


HF100 - PF25 vs. 50i from Martin Koch on Vimeo.

As far as I know Vimeo changes the frame rate to 24 fps so please download and view the original 25 fps QuickTime version at Vimeo which is deinterlaced (I noticed that iMovie '08 exported the interlaced samples deinterlaced although I didn't check deinterlace source video during export).

To show you real interlaced footage I compressed two short original clips using the Photo-JPEG codec (the Apple Intermediate Codec is not available on Windows machines). The two PF25 and 50i clips are recorded at 1/50 shutter speed. You can clearly see the typical interlace combs in the 50i version. Download the samples at www.filefactory.com/file/c1df3c (200 MB).

I'm not convinced by the interlaced recordings. All versions "stutter" on a LCD but I found this is seldom a problem in real life. Also movies in the cinema are 24p and and no one complains that action movies would look bad. I think the movie people have their tricks to conceal any stutter (e.g. slow shutter speed = motion blur). I'll better learn from them and stick with PF25.

The future will be progressive TV displays that display 50p or 60p though.

12 comments:

Gareth said...

Hi Martin,

I live in Hong Kong. My HF100 is also a PAL version as yours. Therefore, the frame rate can be 50i or 25p. I do not know video much so I am very confused about the terms. From the features set in Canon website, it mentions that the cinema mode ("CINE MODE" in manaul) is 24p:
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&fcategoryid=177&modelid=16187#ModelFeaturesAct
In the user manual, it says, "Combine this recording program with the 25 fps progressive frame rate [PF25] to get the enhanced effect of the 25p Cinema Mode"

Which is correct?

Thanks.

Gareth said...

What further confuse me is that the user manual for US version (NTSC) mentions their "Cinema Mode" is 24p (P. 5). There are three frame rate options in US version: 60i normal, PF30 and PF24 (P. 92 of user manual). In our PAL version, there are only two options: 50i normal, PF25 (P. 90 of user manual). Is 24p shooting taken off from PAL model?

Martin Koch said...

I posted a clarification: http://canon-hf100.blogspot.com/2008/06/difference-between-pal-and-ntsc-model.html

Gareth said...

Thanks for explanations. It helps.

Darren said...

Hi Martin,

OK, so I see that you typically use a frame rate of PF25. Would you ever use 50i?

Also, I'm interested in your experiences with the Program settings (P, Cinimode, etc..) and shutter speeds.

I'm really struggling to know which setting to use for a particular environment, e.g. Indoors and low-light, outdoors and cloudy or outdoors and sunny.

I'm at the stage where the footage I'm going to shoot may be a once in a lifetime opportunity, and I want to try and make sure I have the camera setup correctly first.

Thanks for any help!
DJA

Martin Koch said...

Darren, maybe this helps:
http://canon-hf100.blogspot.com/2008/07/what-settings-do-i-use.html

Darren said...

As always a great post!
Keep up the good work... I love reading your stuff

Adam " Vic" Frederick said...

I have a lot video handed to me and I always appreciate properly recorded interlaced footage that I can Smartdeint to 50P/60P. The look is clean and fluid. All other things being equal - crisp beats blurry everytime. 24P is already an anachronism.

brad said...

Hi, I stumbled onto your blog and it has been very useful to me in understanding my hf100(ntsc). I have a question, I primarily use my camera for snowboarding footage(lots of motion) do think 30p or 60i would be better? Would I want to use a high shutter speed to smooth the motion?

Martin Koch said...

I suggest you test it. I never record interlaced so I'm biased. If you want smooth motion you actually want a slower shutter speed with more motion blur. High shutter speeds result in a choppy look.

Olof said...

hi

Found this interesting post and blog. My comment is that that download file above is not available anymore.

Thanks, Olof

Ant said...

Hi Martin, I just found your blog and it has been very helpful.

Sometimes a fast shutter can be desirable to capture fast moving objects - see the Omaha beach scene in Saving Private Ryan.

Cheers,
Anthony