Shutter speed choice for C100 PF

[Al Bergstein]

Given that the C100 is shooting this PF version of 24 and 30p, do we still set, as a rule, the shutter speed at double the frame rate, or because it's a 60i hybrid, we should be setting it at 120???? It seems to work fine for me at 48/50 or 60 but it just crossed my mind today. Thoughts?

[John Steele]

I changed my shutter in settings to degrees and set it at 180, it should always be correct no matter what frame rate I shoot in that way. Don't think you'd treat the PF modes any differently to true progressive though.

John.

[Al Bergstein]

Thanks John. Will do.

[Matt Davis]

PsF mode is progressive, so yes - sticking to half the frame's duration is still 'safe'.

Setting the shutter to 180 degrees does seem a totally logical solution, but 'a word to the wise':

If you get a monitor in shot, you should be shooting at 1/60th regardless of FPS. Unless of course it's a Samsung, in which case you'll need Electronic Shutter Control (ECS) to fine tune it to remove the flicker. Ditto you need to be careful at 24fps that you use 1/60th under certain types of lighting, and if you're shooting NTSC in Europe, you'll need to use 1/50th - which you CAN do if your shutter increments are set to 1/3 stops rather than 1/4 stops. IIRC, LOL.

The 180 degree rule worked well for film cameras in the 'simple' days of film, but now we have to deal with a lot more Fluoro, LED lighting (not nice stuff - the weird architectural and effect lighting that crops up in our backgrounds), computer monitors, computer monitors from Samsung (:rolleyes:) and off-speed slomo/timelapse effects. Not all of the pitfalls of odd funky lighting are visible on the LCD panel attached to the C100, and a separate good quality monitor is a very reassuring thing.

[Darren Levine]

more times than not i stick to 1/60 when shooting 24frames, it's not significantly different in motion, but can keep flickering away and also makes it a fraction easier to pull stills from video

[Gary Huff]

I always shoot 180 degree shutter, or 1/48 for 24p. Why are you shooting 24 PSF if I may ask? The 24p option will give you native AVCHD 24p, otherwise you'll have to remove the interlacing with 3:2 pulldown remove in After Effects, Cinema Tools, or Compressor. A lot of initial C100 complaints because of people shooting in 24 PSF without realizing they needed to process all their footage (it even bit me the first time out).

[John Armando]

Hi to all, seems like we have some c100 pros here so I want to take advantage with some questions. I just picked up my new c100 last week (I already brought it to Canon for the AF upgrade). I hope these questions don't make me sound too ignorant...... My apologies if this has already been answered somewhere else.

Can someone explain the different frame rates that this camera has (60i, pf30, pf24, 24p) what on earth is the difference between pf24 and 24p? And how does the shutter speed relate to these?

I shoot only weddings. Having said that, does it not seem practical to shoot everything in 60i? For reasons such as slow motion, and doing quick pans, etc. My eyes don't see that "filmic" beauty in shooting 24p that everyone talks about. When I set the camera in 24p I get that strobe effect even if I'm slowly panning. To be honest, I don't do much panning but what happens when I shoot the bride and groom moving around or walking or dancing at the reception, won't this screw the editors up when they try and slow mo it? Is it just me that doesn't grasp the concept of shooting like film?

Also, I'm curious to hear from wedding shooters as to what picture profiles you guys use. For me, so far it's a toss up between Wide DR and EOS standard. Any thoughts on these?

Thanks in advance to all for your help!

[Matt Davis]

John, briefly:

Cinema uses 24p, which is also known as the flicks for good reason. Film school 101: pans should take 7 seconds to get object from one side of the screen to the other. You can break that rule for effects. 1/48th is traditional shutter speed, you'll never tell the difference between 1/48th, 1/50th and 1/60th unless you're looking for technical limitations like fluorescent lighting or computer screen issues or filming in Europe. All are legitimate.

24p is true 24p, but the American video systems have interesting issues, so 24p on a video system rather than cinema is actually 23.976 fps - so 24P is 24P, 24PsF is 23.976 frames per second and is actually the safer choice if you think you may go to DVD or BluRay. Taking 23.976 to 24p is absolutely fine for cinemas.

30fps is of course 29.97fps due to the same ever-so-technical 'Connecticut Yankee' clever solution to technical issues. I shoot this for web-only and US stuff. It has just enough extra frames per second to take the edge off the sputtering of uncompromisingly shot 24/25p. If ever there were a 'what's best to shoot for web, video and DVD/BluRay' format, this is it. Unless of course you want to do a European release. LOL.

Then we go through the looking-glass and get into interlaced...

Interlace is a cheat used by 'cathode ray tube' TV sets that required chemicals that glowed when hit by a beam of electrons. Big, hot-running brutes with high voltages, imposing size, and they've pretty much gone the way of the dinosaurs. We all watch by LCD, LED and OLED now, none of which need - or 'do' - interlacing. They sort of interpolate it. They make stuff up.

If you shoot 60i and play it back on a cheap LCD TV, it will look at each frame - it is composed of two fields - and take the first field and make that into a frame. Hold on, that field only used 540 lines. Now it's being displayed at 1080 frames. What happened?

If you're lucky, the TV sort of 'made up' in-between lines, but your original 1080 resolution is actually more like 768 line resolution - sort of like 720p, remember that? If it did the cheap and nasty thing, it just doubled up the 540 lines to make a picture that has less vertical resolution than Standard Definition PAL.

So, although we get 60fps motion from 60i, it looks softer and less oomphy than 'real' 60p.

I only use the interlace modes for slomo - and remember many cameras only do slomo at 720 - which is why they're getting that from the 1080i, downsampled correctly... we see the conspiracy now. HDMI can either do 720p60 or 1080i60 because functionally - they're the same! No free lunch in Engineering. Except lasers. But I digress.

When you split a progressive frame into an interlace signal - which is what PsF is all about - there can be tears before bedtime. Applications like Premiere Pro and FCPX don't see that and may want to interpret your 1080PsF24 or 1080PsF29.97 as if it had to be de-interlaced - which they do for you. Deinterlancing a non-interlaced image is BAD FOR THE PICTURE. So we have to watch out for that. It can be fixed in a few mouse clicks, but you have to know what to look for and when to fix it.

Canon C100 PsF – the fix | Travelling Matt

[Al Bergstein]

Thx all. Superb thread.

[Gary Huff]

Absolutely do not shoot 24PF. Matt is incorrect, there is no 24.00 mode on the C100. The C100 does not shoot 24.00fps like the C300 can. There is native 23.976 (24p) and then there is 23.976 in a 60i container, which is the 24PF option. There is no reason to *ever* shoot with this setting, and if you do you will have to remove 3:2 pulldown via After Effects/Cinema Tools/Compressor. Premiere Pro/FCPX do not remove 3:2 pulldown last time I tried.

[John Steele]

Gary, Matt stated that 24P is 24 and 24PF is 23.97, so there is a 24 mode on the C100 which is the true 24P mode.

John.

[Gary Huff]

Yes, I know that Matt stated that. There is no 24.00 on the C100. Both 24p and 24PF are 23.976. 24p is AVCHD 23.976 and 24PF is AVCHD 60i with 23.976 embedded via 3:2 pulldown.

[John Steele]

Ahh got it :)

John.

[John Armando]

Thank you all but I'm a bit confused. So should I shoot 24p for 24fp?? Again this is just for weddings being edited with Final Cut Pro. I believe the editor still uses slow motion. Would that be a problem.

Thanks again guys!

John

[Matt Davis]

Originally Posted by Gary Huff

Absolutely do not shoot 24PF. Matt is incorrect, there is no 24.00 mode on the C100. The C100 does not shoot 24.00fps like the C300 can. There is native 23.976 (24p) and then there is 23.976 in a 60i container, which is the 24PF option.

Thanks Gary - I stand corrected! :-)