A Big Dilema...

[Polanski]

In a couple of months, I'm planning to shoot a feature length movie, and I have to decide which of these two cameras use. 5D Mark II or GH1.

I have been analizing some 5D footage and it's incredible the quality of the image, the range, but It has two drawbacks: It's 30p and I want 24p. I have also noticed some kind of ghost in the image... I don't know if it is something that has to do with the shutter speed or if it's a fake blur.

On the other hand, GH1 is 24p, but the compression is terrible and also some weird artifacts due, probably, to the big compression.

Is there a shortcut to convert 30p to 24p without too much hazzle. I've been reading about Twixtor, but it takes forever. Also, I would like to know about the ghost on double image that sometimes appears when there's too much motion.

I'll appreciate any comment that throws some light into my conundrum.

Thanks

[morgan_moore]

This ghosting ?

Are you talkng about moving people - I think people dont really get that the rolling shutter causes distortions - its my new bugbear

Im wondering if shooting with a high shutter speed and somehow softening - getting rid of the strobing in post by creating extra frames could help

I think you want to go 5d - compression is a killer IMO

Then youve got to work out focussing

S

[Kholi]

Definitely Mark II my friend. No doubt about it. You can easily conform to 24P, just takes some dedication to your project which you should have anyway.

Won't have to worry about difficult pulldown situations, etc etc.

Better in lowlight, better 1080P in general. Your lighting budget decreases with this sucker.

5D!

[Zak Forsman]

what are some of the good techniques for doing 30p > 24p conversion. i've tried using compressor to straight-up re-time it, but it just drops every 5th frame and looks stuttery... is there a special technique? frame blending of some sort?

[Kholi]

There are two techniques over at Cinema5D for Compressor, and Twixtor workarounds.

Both look pretty good and should look better with a 1/50th shutter, now that we've got shutter control.

Sweet.

[Zak Forsman]

thanks,,,

[morgan_moore]

compressor has drop downs from frame blending to interpoation to a setting that my computer wont even run

good better best on the options tab

I made this crummy vid - ignore the watermark on the screengrab software

http://www.vimeo.com/4145787

S

[Elton]

There are two techniques over at Cinema5D for Compressor, and Twixtor workarounds.

Both look pretty good and should look better with a 1/50th shutter, now that we've got shutter control.

Sweet.

I don't know why people think 1/50 is going to be the best shutter for a 180 degree shutter angle look when the ultimate goal is 24p conversion.

You are exposing 30 frames per second, and as far as I can tell, 1/60 shutter is what you really want for that signature motion blur. Unfortunately, it's been much harder to dial in that shutter speed with the current MKII's exposure compensation mode, so most users have only been able to get 1/50 shutter consistently.

Now that we can actually select 1/60 with the new firmware, in the near future I think you will see more 5D2 clips converted to 24p that have the motion blur tagged.

1/50 looks slightly slurry, IMO. I've been much happier with 24p conversions from 30p/ 1/60 footage.

[Kholi]

I don't know why people think 1/50 is going to be the best shutter for a 180 degree shutter angle look when the ultimate goal is 24p conversion.

You are exposing 30 frames per second, and as far as I can tell, 1/60 shutter is what you really want for that signature motion blur. Unfortunately, it's been much harder to dial in that shutter speed with the current MKII's exposure compensation mode, so most users have only been able to get 1/50 shutter consistently.

Now that we can actually select 1/60 with the new firmware, in the near future I think you will see more 5D2 clips converted to 24p that have the motion blur tagged.

1/50 looks slightly slurry, IMO. I've been much happier with 24p conversions from 30p/ 1/60 footage.

Cool Thanks

[Martti Ekstrand]

what are some of the good techniques for doing 30p > 24p conversion. i've tried using compressor to straight-up re-time it, but it just drops every 5th frame and looks stuttery... is there a special technique? frame blending of some sort?

Have you set the interpolation method like this?

[morgan_moore]

that is too slow for me but 'the best' I use the one above

S

[squig]

You guys could shoot a feature with this update in the US and do 24p in post. But I don't think it's gonna work for the rest of us. There seems to be very little info about shooting with it in the 50hz world and without a 1/25 shutter I just can't see it working in an uncontrolled lighting situation.

[kwoff]

I don't know why people think 1/50 is going to be the best shutter for a 180 degree shutter angle look when the ultimate goal is 24p conversion

Isn't the reason for this that 1/50 is the closest shutter speed to shooting 24p at 180º (i.e., one half of 1/24 of a second, which equals 1/48)? Since motion blur is dependent on the length of time the shutter is open for each frame, 1/50 should yield motion blur that is closer to what you would get at 24p 180º. 1/50 is closer to 1/48 than 1/60 is.

Am I missing something?

Kevin

[Polanski]

All this is really making sense to me. I know for sure the 5D should be the choice for a movie length feature. Nevertheless, it's kind of scary the time it's gonna take to process this footage to 24p using any of the tools available today. BTW, I'm on PC, I'm not MAC guy.
I have already setup two machines for this project. They are dual quad, 8gb of memory and a few TB hard drives configured in a RAID.
I'm planning to use Edius for editing and after effects for compositing and grading.
Why Edius you may be asking? Well, after testing most editing applications, I concluded that Edius is faster and can read almost any format in market today. It also have the capability of playing out REAL TIME to external monitor at 24p through the card that comes in the bundle for only 1,200.
I'll be ordering the 5D next week to get familiar with it before the shooting. BTW, don't, guys, have a link where I can download RAW footage that I can check and see which will be my best choice for converting to 24p.

Thanks for all your inputs...

[Matthew Bennett]

The only thing that makes twixtor fail is very fast motion through the frame... but most of the time it's pretty great.

I'm REALLY looking forward to the ramifications of this update...

[Elton]

Kwoff,

I just go by what my eyes tell me, and in my experience with the 5D2's 1/50 shutter is that it has just a teensy amount of excessive motion blur for each frame to look like 180 degree shutter.

The fact is that your frame rate is not originally 24fps, so those extra frames from 30p need to have a shutter equal to 180 degree angle for the originating frame rate, which of course is 1/60 for 30fps.

It makes sense to me; when you shoot 60p for 24p overcrank, you don't shoot 1/50, 1/60 or even 1/100 shutter, that would most likely look a tad bit slurry and video-ish. Most shoot a 1/120 shutter for a filmic feel--the same principle applies to 30p to 24p conversions.

[Daniel L.]

It's impossible to shoot 1/50 or 1/48 at 60p. The lowest possible shutter setting at 60p is 1/60.

1/60 means that 1 second is split up into 60 sections. 60 fps means 60 sections per second. If you shoot under 1/60 at 60p you would overlap your exposures and not really have 60 unique frames.

Shutter speed defines exposure time, thus the amount of motion blur. 1/60 is always 1/60th of a second, independent of frame rate. This has to look the same at 1 fps, 6 fps, 24 fps, or 30 fps.

[Daniel L.]

Here is an example... Used different values to help simplify. Changed the font to something that would allow an ASCI demonstration. If this is a mess on your end it's a font problem.

[10 frames per second (FPS)]
0:00-----------------------0:01
_______________________________
|1 |2 |3 |4 |5 |6 |7 |8 |9 |10|
_______________________________

[1/5 shutter]
0:00-----------------------0:01
_______________________________
| 1/5 | 2/5 | 3/5 | 4/5 | 5/5 |
_______________________________

1/5 shutter only fits 5 exposures per second, so every 2 frames at 10 FPS would be duplicates. That's not 10 fps, that's 5 unique FPS. That's why 60 fps at 1/50 shutter is not 60 fps.

If you want the motion blur of 24 FPS with a 180 degree shutter at 30 FPS shoot at 1/48. It does not mater what your frame rate is. Well.. It does, but that's another subject.

Feel free to correct any mistake on my part :)

[Polanski]

Did I misundertand or with Twixtor I have to convert to 59.94i and then back to 23.976p?
Or can I go from 30p directly to 24p?
what's the real process here?