EOS 5D MK II workaround: Converting 30p into 24p/25p

mattsand said:
I know you're not in paris, and i know for sure lee isn't. I think you said you travel a lot though so who knows. As for joking sorry for the low quality but you still haven't gotten mine. :-)
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Now? Maybe not, maybe yes. Something I know as far as your posts concern. You have a POV about yourself. This is the ultimate starting point for anyone, better than anything else. Your own can be not so far. Or at least, not so. Humbleness is something that also usually helps. Not that I should recommend to you. Keep going on your readings. :thumbsup: :-)
 
Emanuel said:
I've found this:


«You can edit in 30P, then when finished, run the footage through a conversion to 24P. Apple Shake and Motion have Optical Flow technology that works very well for this. It is not frame blending, the frames are completely redrawn using an advanced technology called Motion Vectors. The result is cinema quality. If your footage going in is 180 degree shutter, that will be the angle generated. It works best with Progressive to Progressive conversions since the Interlacing can lead to some flickering between frames.

I do this quite often for TV commercials and DVD's that often look better at 24P in Standard def. That said, I prefer the look of 24P in standard def since DVD's and Plasma TV's will remove the pulldown automatically and thereby increase resolution. In native HDTV environments I prefer the look of 30P for most footage since it just locks in with most Display refresh rates better with less flicker.

Shooting in 30P is the better choice all around since the Optical Flow conversion works best when "down converting" frames rather than raising the frame rate.»


http://cinema5d.com/viewtopic.php?f=13&t=25&p=284&hilit=conversion#p284


«As I've said about 30 times around here lately, (it*) can be easily and perfectly retimed to 24P if you have Apple Final Cut Studio's Motion app, or Apple Shake. The technology is called Optical Flow, and alternately may be called Motion Vectors.

30P is a serious limitation of the camera only if you don't have the right software. Most if not all indie filmmakers have this software. It's like the Photoshop of film making.

In the vast majority of footage, 30P will look better on an HDTV. 24P is only superior in SD when delivered over DVD compression.»

* typo (in the original text it is mentioned 24p) as far as I could understand


http://forums.dpreview.com/forums/read.asp?forum=1032&message=29496902


~ Matthew Thomas

http://www.thomasarts.com (company website)
http://gallery.me.com/thomasarts (company photo working gallery)
http://gallery.me.com/mthomas
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Emanuel said:
The answer comes here:


«You make it sound so easy! If only it was.. :-)

I work in Visual effects, and I've been working in the field for years. I've personally worked with most major compositing packages over this time. Shake and Nuke both have optical flow methods and both are very good (we use them mainly to retime shots, make them longer etc.) and for certain shots, you would be hard pressed to tell it wasn't originally shot like that.

BUT, in order for optical flow to work successfully at all, you have to have footage that lends itself to be retimed nicely in the first place. A good example of a shot that is horrible for retiming, is a crowd shot from waist level stacked on top of eachother. The algorithm to calculate the motion vectors that optical flow uses, will have a hard time tracking what belongs to what, creating artifacts in the rendered frames. This is but one example, many shots with countering motion between parallaxing objects are headaches to deal with.

(...)

Taking my notes above, my point is that software will only work when the footage is agreeable. And even then, it isn't quite the same as film with a 180 degree shutter.. But certain types of shots work much better than others.

I also want to note, that not all 30p footage is the same. The motion blur from standard film is about 2 times faster than 24p, so about 1/48th second per frame. This creates the familiar motion blur we associate with "film". Many 30p sources are shot at faster shutters, creating more crisp "video" looking footage, like Vincent Laforet's latest short film "Reverie". That's the main reason it still looked like video, as beautiful as it was.

30p shot at a shutter speed of 1/48th would be much closer to a film look than using the shutter that they had used at but with 24p output. 24p AND 1/48th are necessary for the look.

Back to the topic, my point here is that to achieve a "film" look, and not just convert video footage to different frame rates, you need to capture the footage the real way. Software as you pointed out, can help, but they are limited and need a lot going for them to be truly successful.»


~ Nordin [ LINK for profile] http://rahhali.com


EDIT -- Here's the link:

http://forums.dpreview.com/forums/read.asp?forum=1032&message=29497059
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There are some further replies on the subject matter:

http://forums.dpreview.com/forums/read.asp?forum=1032&message=29501437

«apples' optical flow is not the same as frame blending. Please look this up on the web or here. I've described it several times lately here in minor detail. Apples' website has a much better explaination. Adam Wilte also has some nice tutorials that explain it.

Optical flow creates entirely NEW FRAMES that didn't exist before. It doesn't just blend and overlay existing pixels. It by default uses the same shutter angle (shutter speed) as it senses in your source footage. So if you are shooting close to a 180 degree shutter in 30P (1/60sec) The optical flow process will turn that to a 48th/sec if you are retiming to 24P.

Using Optical Flow is easy but the files it uses to create the new frames are called Motion Vector files and are essentially 20X larger than the footage files. When you've retimed, you can delete these, but I tend to keep them around for future retiming.

Again, using retiming is a pain. Many will not do it and just complain about the camera because they don't trust that such a feature can look as good as it does. My goal in this forum is to provide people solutions to the limitations of the camera so they can stop complaining and start posting work again.»

~ Matthew Thomas


And here comes the answer:

http://forums.dpreview.com/forums/read.asp?forum=1032&message=29503862
 
bronxjragon said:
seriously, this is the d90 forum..
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Look, Bronxjragon: Since this forum has been started there were discussed both cameras, the d90 AND the 5D. It's basically a forum for hybrid DSLRs and it will be so until somebody creates a separate one for the 5D.

But I can live with the status quo: There are so many issues both cameras share that it makes sense.
 
joe 1008 said:
Look, Bronxjragon: Since this forum has been started there were discussed both cameras, the d90 AND the 5D. It's basically a forum for hybrid DSLRs and it will be so until somebody creates a separate one for the 5D.

But I can live with the status quo: There are so many issues both cameras share that it makes sense.
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not really
 
Who would do and why? :)

Emanuel said:
You are both surely right. I had applied myself to be a mod here (other cameras sub-forum) a long time ago. Despite you can't find native* mods in this part of dvxuser.com -- an excellent moviemaking community since its beginning. However, Jarred is not too much in this extra mood. His business is not to support a DSLR shooters community.

* I mean, outside the DVX or HVX realm.

Another interesting fact is how much free this sub-forum is. Sometimes, it doesn't seem to be owned by one of the RED project heads. I must admit, I have read some unpleasant points, at times. We should all know, this is RED's house too.

On the other hand, the fact is D5 Mark II has immersed D90, as well, a complete new DSLR market has emerged.
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Lee, two questions:

1) What was the shutter speed of the original footage?

2) Where did that guy learn acting?
 
You can inform on the 5d all you want. The more we learn from this new cameras the better. Don't pay attention to the complainers. They are everywhere and all they do is get in the way of progress.
 
I suppose that impression comes from a slow shutter, probably 1/30, but I would like to have the confirmation from Lee about that.

Emanuel said:
They eat kids at breakfast.
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As long as they post it on vimeo that's fine :evil:
 
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