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Old June 25th, 2009, 12:48 PM   #1
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Addressing Motion blur in Progressive modes.

Hi,
The motion blur during pans and on moving objects when shooting in Progressive mode is something I don't understand. Is there a way to check that? Shooting interlaced on my HM100 gives a much cleaner footage but it has that 'videoy' look. Progressive addresses that but the picture goes for a toss no thanks to that blur. I was really excited about shooting progressive, but is there a way to fix that since I intend to shoot something in 24p or 25p and transfer to film later? At this rate I'd rather stick with 50i...
Thanks...
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Old June 25th, 2009, 01:09 PM   #2
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24p/25p in all cameras, (film/video) should be 1/48th and 1/50th shutter speed generally. 60i/50i should be 1/60th and 1/50th as well. There is about the same amount of blur to be honest. What is really happening is there are less frames per second in 24/25p compared to 60/50i interlaced fields (notice I didn't say frames.. ) that make up a supposed 30/25 frames that at no time ever really exist. So interlaced video seems smoother, but it also has lower resolution and your HDTV is making the odd or even lines as to how what it thinks the lines would be. A good 24/25p SD looks as good a many 1080i cameras for that reason.

Now if you referring to "Juddering" in panning and zooming, that is something you can deal with while taping. old rule (80+ years?) panning or having subjects cross the film plane should take 5 seconds or longer on typical 4:3 or 16:9 aspect ratio. Longer for wider format cameras. You can pan faster as well, (whip pans).

There is a speed that many of us used to pan and zoom with 60i/50i cameras that don't translate well to 24/25p cameras.. so short story, pan and zoom a little slower or faster.
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Old June 26th, 2009, 11:57 AM   #3
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Thanks Alex..

I'll try with different shutter speeds as you suggested and keep you posted. But as you may know, it's won't be always possible to control the movements within the frames.

So you suggest I keep shooting in progressive if I want to convert my footage to film later?? Even seeing shots frame by frame, I'm worried that blur or the 'juddering' will copy directly on film, and will be even more prominent on the big screen..
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Old June 26th, 2009, 05:56 PM   #4
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For any fast motion I would use 720/60p.
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Old June 27th, 2009, 12:55 AM   #5
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since film is 24p 1/48th second standard, i would advise to experiment a lot with it and get used to it.... I shoot everything from sports and action etc in 24p 1/48th. It forces me to be a little better camera operator to remember what I used to do with 16mm and 35mm film. Have to unlearn a lot of bad habits from video 60i.

If you shoot 60p at 1/120th, if you are NOT planning on footage for slow motion later, then you will have UGLY shutter speed issues if your final 24p etc. If you shoot 60p at 1/60th then you have nearly as much blur as you were saying you didn't like. 1/100th still starts looking like the action scenes of SAVING PRIVATE RYAN... so be careful and use your ND on Max in daylight.

If your friends have kids, go tape a soccer game or softball etc and shoot an entire game and experiment. The reason I suggest it since you really won't have control over your subject so it makes you make decisions on the fly. Some will be good, some will be bad, but you will learn from it. Focusing, zooming, panning, shutter speed, frame rate etc.

Also if you end up distributing via iTunes (largest legal music and video content in the world) the only HD content they do is 720p @ 24fps. 30fps or 60i HDV comes out as 960x540 @ 30fps. not bad really.. but it's closer to European PAL than HD. You might find later that the magical "HD" might sell more content as well. Just a feeling of mine.... since I buy or watch HD before SD.
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Old June 27th, 2009, 12:47 PM   #6
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Alex, first of all a lot depends on your output. If it is broadcast application 30/60 frame rate is a must. I worked on several docs like this: YouTube - Oregon Field Guide Ice Climbing - Part 1 and a lot of them were filmed just in 60i.
I also worked on some ski and mtn bike projects- all of them filmed in the past in 60i, however on the recent Red Bull shoot by Bella Coola B.C. 720/60p was used a lot.
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Old June 27th, 2009, 05:23 PM   #7
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Alex,
your insights are a real eye opener. Something I am beginning to learn to deal with...It's all in the shoot stupid..not just the cam. LOL. Interestingly I dug up another article that mirrors your exact sentiment, maybe of interest to other readers like me out there.

Thanks for your help, and am looking forward to deriving more out of your tos and fros with Robert ;-) Keep it coming guys.
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Old July 7th, 2009, 03:36 AM   #8
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Quote:
Originally Posted by Amir Jaffar View Post
It's all in the shoot stupid..not just the cam. LOL.
Well not exactly. There are many reasons why low-cost HD cameras shooting at 24, 25, and 30 show far more judder (both "sampling" judder and "2-3 pulldown" judder) than do CineAlta and Varicam cameras.

If you want to understand why this is the case, click to Broadcast Engineering at:

Broadcast Engineering and Digital Television

Now search for "mullen" and select the "24p judder" story OR simply click to:

24p judder

The advice of "correctly select shutter-speed" and "shoot right" will never enable you to duplicate the judder of 16mm or 35mm film stock or that of an expensive HD camera with an expensive lens. The advice can certainly help you, but only $$$ solves the problem fully. There's a reason why folks rent HD cameras and carefully choose prime lenses when they plan to shoot HD to go to film.

You might want to ask yourself a couple of questions:

1) what is the real chance you'll have the money to finish to film?

2) does the subject matter really lend itself to 24p/25p GIVEN judder will be high. Are you sure 720p50 isn't going to look better in the end?
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Last edited by Steve Mullen; July 7th, 2009 at 04:41 AM.
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Old July 7th, 2009, 07:18 AM   #9
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You can also use panning speed charts if you're using 16/35mm adapters.

I have a German one, but you can google and find items like this: Panaflex users' manual - Google Books

I don't know if anyone has computed a panning speed chart for 1/3 lenses

Most of you panning/motion problems can be solved with careful pre-production (except in surprise documentary situations, e.g.), as is true for many depth-of-field issues.

This wonderful site has some great resources & tips !
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Old July 8th, 2009, 01:48 PM   #10
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oh well.. bust goes the bubble... again.

you are right Steve, no amount of permutaion and combination of shutter speeds or aperture settings etc. improves the judder on my HM100. I guess as you said, it's the 1/4th inch CCDs that are the culprit here.

However, can you please tell me if I shoot in 1920X1080 50i, ( which does not judder btw) will I be able to successfuly transfer my footage to 35mm film? assuming I manage the audio separately. I mean wouldn't an interlaced film transfer from a 1/4th inch camera be better than a progressive transfer?

Thanks.
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Old July 8th, 2009, 02:25 PM   #11
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Amir, I just don't see why do you insist on shooting 1080? 1080 resolution with these cameras (as well as many others) is achieved via pixel shift. However they record 720 native. I filmed ski and mtn bike footage and the best results were achieved (mostly with HVX200, 2 days with HM100) in 720/60p. (not in 1080/30 or 24) I also shot some footage with GY-HM100 and for faster motion I used 480/60p option, as the matter of fact the footage looked better then 720/30 or 720/24p in regard of motion blur.
I don't understand this obsession with "film look". From a historical perspective it doesn't make any sense. Way back when all the news footage was shot on 16mm film. But now nobody expects "film look" in the news, the video look is what everyone expects. I mean if you want that "film look", shoot film. 99% of the content will end up selling a few hunded to a few thousands of copies on a DVD or will be distributed on the web or will never see the world beyond edit bay. So I'd say don't sweat over the technicalities (to a degree, after all it should look decent), and have fun with it.
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Old July 8th, 2009, 02:48 PM   #12
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well, to go with Robert's post, "film look", so to speak, is not just dof and controlled motion blur. what distinguishes a theatrical motion picture from video newsreels or tv documentaires is another approach to lighting, blocking, composing in the frame and movement in and out of it, instinctive or deliberate use of film grammar, sophisticated camera movement, and many more criteria. also, not all stories deserve a 35mm or widescreen treatment.


Furthermore, cult films such as Aronovski's "Pi" were shot in 16mm; more recently, the lovely "Once" by John Carney was shot with a standard HVR-Z1. so - film look has a little to do with the camera and a lot with the director's and DP's ability to stage and direct.
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Old July 8th, 2009, 03:10 PM   #13
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Claude, I don't know if you had a chance to see a documentary "The Bridge" THE BRIDGE ::: The Movie ? This doc was shot with XL2's and for one moment I was not thinking how this movie was shot. I think there are numerous samples of other movies (Slumdog, Jesus Camp, Deliver us from evil, Gabriel and many more), shot on simple equipment. The most watched Discovery program "Deadliest Catch" is shot in HDV with Canon A1's (mostly). I'd say content, content, content. Like you pointed out: lighting, shot selection, captivating story, interesting characters, and not forget edit will make a great documentary or a film.
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Old July 8th, 2009, 03:18 PM   #14
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Robert, this looks like an amazing movie, i MUST get hold of the dvd.

as you say, story, characters, content - an issue many filmmakers struggle with, especially with docus, myself included.

luckily, my present producer pushes me hard on story development, and he's right.
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Old July 9th, 2009, 04:24 AM   #15
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Hey Robert..
Guys shooting FICTION will always be obsessed with the film look. You can't help that. You just get conditioned that way having grown up admiring, learning and seeing movies - movies that were shot on film. They'd rather die than see their film looking like an afternoon soap.. YUK! (which btw are shot on high end cameras too) Haha.

But the harsh check on reality is that film is expensive to shoot on for Indiemakers. So it's no wonder our excitement knew no bounds when we came to know there are affordable cameras out there that can emulate the film look without us having to shell out big bucks for stock, processing, developing, telecine etc. - not to mention the long and cumbersome process involved. And a film judder in the footage is the easiest way to achieve that ;-)

Shooting on non film stock cameras is the future, sure.. but the filmmakers are taking that route only because they are convinced that the new cameras give them that look. Even if Lucas, shooting on HD, was intending a video only release , he still would have perhaps converted it to film and then back to video before releasing it on DVD.

And you are right.. Sure you dont' need film cameras or film look for shooting mountain bikes or nature. Ditto for newsreels and documentaries. But dramatic film making does require those..even if going by the fact that audience doesn't really care what format it's shot on as long as the content is captivating enough for them.. But as a filmmaker I'd still want to give it to them with a film look and not video - even if it's high end. I can't say why? it's just built in the psyche. or like you said obsession. haha.

Regards..
btw the hot pixel on my HM100 still needs to be fixed :-(
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