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Old May 18th, 2008, 05:22 PM   #31
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I shoot 99% 30p for exactly the reasons you said. 24p looks lousy to me.
And it used to be said that you have to pan or tilt "slowly" in 24p, now it looks like people are saying don't pan or tilt at all! That's an impossible limitation. Hollywood films DO pan, tilt, dolly, track, they do it all the time. 30p looks nice though. I've embraced it.
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Old May 19th, 2008, 03:08 AM   #32
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Maybe I didn't make myself quite clear about the panning and tilting.

I certainly didn't mean that you must not use these techniques when using 24 or 25fps but you SHOULD apply different methods in doing so, which is why I posted the link to PANNING TIMES as an example. As for zooming, I personally think it shouldn't be used in anything! The zoom was originally invented as a way of only using one lens instead of keep changing. Any 'zooming' was done in between takes for a re-frame. I hate zooms. Very rarely do you see the zoom used effectively.

Alex your suggestion of a guidance document for all those videographers and cameraman even of many years experience such as myself would be excellent. It took me quite a while and lots of trial and error to understand how differently 24 and 25fps on HDV to that of normal video. I imagine its a common occurrence for people used to video to be disappointed with their first foray into 24/25fps HDV.

I have to say on a personal level I found it really fascinating to learn an almost completely new skill after being so at home on video for so many years.

For me, the most important things I learned to get the 'film' look were;

1: Light differently to that of TV (I've been industry trained in Location and Studio lighting and I'd say I use different techniques when shooting 24/25fps HDV)
2: Reduce the depth of field wherever possible (buy a 35mm adaptor as a start perhaps)
3: Pan and tilt differently. According to your subject and remembering your panning times.
4: DON'T ZOOM - Track instead!
5: Spend as much time as you need in composing your photography.
6: Don't rush anything.

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Old May 19th, 2008, 04:38 AM   #33
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I shoot 99% 30p for exactly the reasons you said. 24p looks lousy to me.
And it used to be said that you have to pan or tilt "slowly" in 24p, now it looks like people are saying don't pan or tilt at all! That's an impossible limitation. Hollywood films DO pan, tilt, dolly, track, they do it all the time. 30p looks nice though. I've embraced it.
An often overlooked point in a discussion regarding JVC's 24p and its so-called 'judder' compared to the look of cinema releases is that while the films are shot at 24fps they are in fact projected in the cinema at '48fps' i.e. the frame is doubled, to help smooth out the motion -hence the pan, tilts, dolly movements etc do look a lot better on the big screen. Just ask your local projectionist and he will confirm this (I work in a cinema and the projectionists have all confirmed this vital point).
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Old May 20th, 2008, 11:41 AM   #34
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"while the films are shot at 24fps they are in fact projected in the cinema at '48fps' i.e. the frame is doubled, to help smooth out the motion".

I'm sorry to say, but this is simply not true. I was a projectionist for seven years, and film runs through a projector at 24 frames per second. The confusion may lie in the fact that since the shutter is closed 50 percent of that time, the effective "shutter speed" is 1/48th of a second, but the fact is that the film runs at 24. Even if the film rate were somehow "doubled", there is no way that showing an image twice in a row would somehow create a smoothness that wasn't recorded by the film camera. Well, unless it was run at double speed, which certainly you can't be suggesting, as the actors on screen would move faster than Keystone Kops and talk like chipmunks!



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Old May 20th, 2008, 12:03 PM   #35
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I feel I should clarify something here: I'm actually a documentary videographer so dolly shots and the controlled camera/subject motion discussions are null and void in most of my work. I don't do Digital Cinema but I was looking for a quasi-surreal tone for some of my more engaging story driven pieces.

I start shooting in about an hour on the next piece so I'll need to start (and finish) this story at 60P. I will take all advice given in this thread to heart and will begin to teach myself a "new" way of "filming" in video, just to have the skill set available to me.

Tim: I haven't had time to re-upload the "test" footage. I will endeavour to upload some new footage shot on this piece when I can as well as some more "practical" 24P test material.

I'm not done with this discussion - I just have a real world deadline that I need to meet. Again, thanks to all for sharing and please continue to do so. I learn more each day I log in here.
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Old May 20th, 2008, 01:14 PM   #36
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"while the films are shot at 24fps they are in fact projected in the cinema at '48fps' i.e. the frame is doubled, to help smooth out the motion".

I'm sorry to say, but this is simply not true. I was a projectionist for seven years, and film runs through a projector at 24 frames per second. The confusion may lie in the fact that since the shutter is closed 50 percent of that time, the effective "shutter speed" is 1/48th of a second, but the fact is that the film runs at 24. Even if the film rate were somehow "doubled", there is no way that showing an image twice in a row would somehow create a smoothness that wasn't recorded by the film camera. Well, unless it was run at double speed, which certainly you can't be suggesting, as the actors on screen would move faster than Keystone Kops and talk like chipmunks!

Todd Norris
Todd-

I think you misunderstood my post. The term '48fps' was in inverted commas to indicate that this was not to be taken literally and was refering to 'perceived' or 'effective' frame rate... of course it would be at double speed if it was really 48fps! But I have been informed by both our local chief projectionist as well as from other sources that 'most modern projectors strobe each frame twice, or more, so that the apparent frame rate is faster to reduce flicker by giving the impression of 48fps projection'.... I am not sure if this could be by having an effective shutter speed of 1/48th that you mention or whether this is a modern upgrade that has occured since your time as a projectionist. I will check with our chief projectionist when I see him again to get the correct technical explanation of how this is achieved -whatever method is used it certainly explains why we don't see the 24p motion 'judder' refered to in this topic.
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Old May 20th, 2008, 07:06 PM   #37
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4: DON'T ZOOM - Track instead!
Stuart
Yup.. Try not to zoom, unless you have a reason to. we are of course talking narrative. Kubrick hardly zoomed, but when he did, it was usually a long slow zoom or really long and fast, usually in a very disturbing scene. Today, the rules have changed a little on narratives.. SAVING PRIVATE RYAN/BATTLESTAR GALACTICA etc, have tons of hand held zooms, but that is a narrow stylistic choice.

Now in the defence of zooming, the JVC HDV 100/200 series combined with a Varizoom or the (probably) beetter built JVC zoom control have some really nice slow creeps. I havn't timed it from wide to tight, but I believe it was in excess of a minute. slow and repeatable. Highly recomend it.. however when stowing a Varizoom control for traveling, take the time and remove it from the tripod and bag it... otherwise sooner or later (or me this week) cable snagged while on the dolly going to the shoot, and soooo I had to shorten the 8 wire cable by about 6 inches. Not a big deal, but I did stare at the bare wires before the shoot and said to myself... "That was stupid, next time I'll pack it correctly"
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Old May 20th, 2008, 08:37 PM   #38
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I' mot sure the faster frame rate is to smooth out the image on the big screen as much as it is to shorten the individual dark zones in order to reduce the perception of flicker.

On the other hand, maybe it's the case that the perception of flicker also gives the perception of judder whether the frame rate does or not. Perceptual stuff is all very confusing.

The more I learn about sound and video the more I realize that we don't hear or see anything the way it is because there's so much filtering and processing going on between our ears.

I play tuba and know for a fact that if you look at the energy at different frequencies you'll find that there is almost zero energy at the low frequencies associated with the instrument. The brain will take the higher harmonics in combination and synthesize what we think of as the low notes of the instrument. In long ago times, churches that had no space for the longest pipes on an organ would get organs made with a pair of higher frequency pipes tuned appropriately to generate the perception of the low notes. This is a well known organ builders trick

The human eye is made up of discrete receptors (rods and cones). So there really is no such thing as a continuous image input to the brain.
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Old May 21st, 2008, 03:09 PM   #39
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I stand corrected on the issue of film projectors. You are correct that modern projectors display each frame twice (sometimes three times) before moving on to the next frame. It turns out that the aging art-theater I worked at had an old projector that did not do that. Go figure. Always good to get new information. Thank you.
Perhaps this is supposed to be the appeal of 120Hz HDTVs. Double the scan rate and reduce the perception of flicker.
However, having shot 24p with the JVC HD250 and also with a Varicam, or even a DVX100 for that matter, I have noticed more judder in the JVC compared to the other two. The Varicam is basically indistinguishable from film, in my opinion, in regards to motion smoothness.

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Old May 21st, 2008, 03:39 PM   #40
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I stand corrected on the issue of film projectors. You are correct that modern projectors display each frame twice (sometimes three times) before moving on to the next frame. It turns out that the aging art-theater I worked at had an old projector that did not do that. Go figure. Always good to get new information. Thank you.
Perhaps this is supposed to be the appeal of 120Hz HDTVs. Double the scan rate and reduce the perception of flicker.
However, having shot 24p with the JVC HD250 and also with a Varicam, or even a DVX100 for that matter, I have noticed more judder in the JVC compared to the other two. The Varicam is basically indistinguishable from film, in my opinion, in regards to motion smoothness.

Todd Norris
Really? I figured a Varicam with larger sensors and shallower depth of field is obvious that it would be less, but the DVX100 has less? Hmmm Not what I would have guessed. Unless there is a relation not only to chipsize and lens, but resolution of the chip? Ok.. I guess it makes sense... (assuming same focal length, shutter speed, camera movment etc)

Incidently, where do you set your detail setting on your JVC? I keep mine at min to -8. With Normal I see a lot more of everything I don't like to see. If you are at NORMAL I wonder if that might be sharpening the background and emphasising any juddering you are seeing?
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Old May 21st, 2008, 04:27 PM   #41
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I usually have the detail set to -8 or -9. Yes, at Normal, there is too much detail and everything gets a sort of "ringing effect" around the edges, and I think that makes the judder seem worse.
As far as the DVX100 seeming smoother, it's probably subjective on my part. Both it and the JVC have 1/3" CCD's, but perhaps since the DVX is SD and not HD, there is a softening of the judder effect. Without trying to start any controversial topic here, I am very fond of the "filmic" look of Panasonic's cameras in general. But I've been using the HD250 for almost a year and I'm very happy with it.
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Old May 21st, 2008, 06:10 PM   #42
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Incidently, where do you set your detail setting on your JVC? I keep mine at min to -8. With Normal I see a lot more of everything I don't like to see.
One of the samples Tim Dashwood has online for his ProHD video is on shapening. You can see it on this page by clicking "Sample 1":
http://www.dvinfo.net/prohd/preview.php
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Old May 21st, 2008, 06:53 PM   #43
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Both it and the JVC have 1/3" CCD's, but perhaps since the DVX is SD and not HD, there is a softening of the judder effect. Without trying to start any controversial topic here, I am very fond of the "filmic" look of Panasonic's cameras in general. But I've been using the HD250 for almost a year and I'm very happy with it.
You know.. maybe just to beat a dead horse... I'll shoot some boring panning and zooming this 3 day weekend on the JVC but in SD 24p Wide and see what it looks like, especially after I get it to DVD. I did some methodical testing before and I still prefered the HDV downconverted to DVD more than the SD 24p, but just to see if there was something to HDV being a little twitchier than SD 24p you experienced with your DVX100.

Hmmm... for a lot of what I'm shooting, I might as well be shooting 24p DV Wide anyway since I'm not going to master Blu-Ray for this stuff anyway, and it would save me tons of time on downconverting. Hmmm... need to find a victim I mean a volunteer to run around in the sun repeatedly. Hmm..
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Old May 22nd, 2008, 06:19 AM   #44
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If you've got an HD or HDV camera why choose to shoot in SD just because that's your output?

I'd recommend shooting in highest quality and going down from there, not starting from a low point! And as for the extra time spent downconverting? What extra time?

At the moment we shoot all of our corporate stuff in HDV and it ends up on sd DVD. There is no 'extra' downconverting process. This all happens in the render. Right? Unless I'm missing something completely obvious?

Going off topic here a bit maybe!
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Old May 22nd, 2008, 12:52 PM   #45
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If you've got an HD or HDV camera why choose to shoot in SD just because that's your output?

I'd recommend shooting in highest quality and going down from there, not starting from a low point! And as for the extra time spent downconverting? What extra time?

At the moment we shoot all of our corporate stuff in HDV and it ends up on sd DVD. There is no 'extra' downconverting process. This all happens in the render. Right? Unless I'm missing something completely obvious?

Going off topic here a bit maybe!
Oh, just to save time.. about 1/3 the output render time as downconverting HDV to DVD. Even the SD 24p I shoot with the JVC is 100x better than any of my competitors in two counties, everyone is thrilled if I show up for an event. I just seem to remember that the HDV downconverted to SD DVD widescreen still looked significantly better to NTSC widescreen 24p to DVD. I won't bet a lot on that, but that is what I remember. Now for anything that I"m working on for me (documentary/narrative etc) I always shoot 720p. For some of my projects for friends and families where there is little money, I doubt anyone could see the difference and it would save me lots of time. I still probably wouldn't shoot NTSC since I always want to get the best to a friend or a customer. Now I do shoot NTSC when I'm lead camera on other local broadcast etc, since thier equipment isn't HD and it would be a HUGE waste of time for them. Match the color, shoot, hand over tape and walk away.
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