View Full Version : General question about HD footage
Ryan ONeil December 5th, 2009, 04:30 PM I'm somewhat new to the videography world and I've got a question about the benefits of using one type of footage over another. I understand what the terms 1080i/1080p/720p are as well as frames per second.
My question is: what influences you to use one framerate over another? What about 1080i or p or 720? Are there certain conditions that would help decide which to use?
I'm not an artistic minded person. I'm a math person. At least while I'm learning, I'd prefer to have set parameters in which I use certain settings instead of just saying "This looks better." I'm still learning what good video is really supposed to look like.
Thanks for the help!
Milutin Labudovic December 6th, 2009, 05:31 AM 720 or 1080 is just a resolution difference, and as for p or i, it should be i for interlaced and p for progressive or 24 separate frames, like with an old sector cameras. but in practice i think they are all interlaced.
the 24p they say gives you better low light value, on my canon hv30 - i have not noticed any difference.
and as for cinematic look on 24p, i think it is an urban mith. i have not noticed difference, the film look is in post production only.
the good video is supposed for starters to have appropriate WB (make a lot of experiment to see difference) for the condition pictured, but on day light auto WB usually does the job.
then there is inevitable video look on the cameras, which is debated a lot - to avoid it i don`t know how, except in post production - and it is dependent from camera to camera. i have noticed that still cameras usualy have a film looking video, o contre to the video cameras, do it should be differnt.
don`t pan and zoom a lot (or at all) during shooting to get more professional feel, use your camera like a still photo camera, frame a shoot and leave it. let the subjects move in the shoot.
and of course practice makes it perfect, now days cameras are all excellent, and only thing is human/users perception and felling that matters.
watch koyaanisqatsi and baraka, it is grammar of the shoot. with today technology, everybody has a opportunity to shoot frames like in those two movies (do baraka was shoot with exceptional 70mm camera)
practice & experiment
Brian Drysdale December 6th, 2009, 05:52 AM Frame rates tend to depend on if you're from a NTSC region or PAL. Film has traditionally been shot at 24 frames per second and some people in NTSC regions like the look for use in video, in PAL regions they shoot at 25 frames per second for video & TV - 24 fps being the preserve of cinema. 24 fps (actually 23.98fps in the world of video) tends to be used as a universal HD frame rate for TV drama series. In NTSC countries they use 29.97 frames per second (commonly referred to as 30fps).
Progressive frames are whole single frame, they are not interlaced.
Best look here:
High-definition video - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/High-definition_video)
Tim Polster December 6th, 2009, 03:11 PM Hi Ryan,
The framerate is really what you choose and it should be based on your delivery method, how much action will be in your footage and what type of look or "feel" you want to want to achieve.
24p - slowest of the framerates. Does not handle camera motion very well unless very slow. Has a real sense of capturing an atmosphere. Best used for storytelling, drama but can add that look when used in action scenarios. Think NFL films. When you watch a football game live, the footage is shot at 60fps, but when you watch NFL films the game footage seems like a special event that happened in the past. They use 24p and a lot of slo-motion to achieve this. A perfect example of what 24p can add.
60i/60p - fastest of the framerates. Hnadles motion very well. Handles camera movement very well. Has a real "present" feel to it. Like the footage is happening live. Best used for high action like sports and live broadcast. I prefer 60p as you can do more with the footage in post as you captured whole frames instead of fields with interlaced.
30p - well the forgotten framerate. This is a hybrid between 24p and 1080i. It handles motion pretty well and it has a bit of the 24p mistique, but its only native output format is from a computer file. DVD or Blu-ray do not support this format. So anything you shoot has to be interpolated into 24p 720p60 or 1080i for DVD or Blu-ray ditribution. This is a great format for web video.
Hope this helps!
Chris Barcellos December 6th, 2009, 03:19 PM 60 i is 60 half frames (every other line) per second. It is essentially 29.97 NTSC standard for television production.
60p is 60 full frames. P refers to fact that each frame is complete in itself. Thus with 60p, you can slow play back to 24frames per second and get clean slow motion playback.
24p is just that, but shot at 24 whole frames per second. It is more subject to motion stutter, but also is the closest to film shooting, and thus perferred by those looking for the "film" look.
Ryan ONeil December 6th, 2009, 10:04 PM Thanks! Ya'll are definitely answering my questions.
What about shutter speed? I know it affects the brightness of the film. What areas of the film world are different shutter speeds used in?
Tim Polster December 7th, 2009, 12:03 AM Shutter is usually twice the framerate.
24p - 1/48th (use 1/60th for less motion blur)
30p/60i - 1/60th
60p - 1/60th or 1/125th
Ryan ONeil December 7th, 2009, 10:58 PM Never knew shutter was the simple. (I'm sure it can get more complex but still...)
Tim Polster December 8th, 2009, 12:40 AM In my experience, shutter speed is far more for the still world where you only have one frame to deal with and freezing motion is very important.
Video has many frames so motion blur is actually part of the look, plus the frames change so fast you do not get to process as much visually.
You can change it but for the most part those simple guidelines will take care of most situations.
Ryan ONeil December 8th, 2009, 11:55 PM So, what's best for wedding settings? 1)Low light, 2)Outside/sunny, and 3)lighter inside?
Brian Drysdale December 9th, 2009, 06:42 AM The standard settings are what you'd normally use for weddings. Use ND filters to reduce levels in the sun rather than the shutter unless you want the wedding to look like an action scene from "Saving Private Ryan".
Shutter speeds are sometimes reduced (or even switched off) in low light conditions, however, just be aware of blurry motions and if they're becoming excessive. Also, you may wish to set the shutter to avoid flicker from lights (1/60th in 60hz areas or 1/50th in 50hz areas).
This applies only to progressive where you must have the shutter on. With interlace it's usually switched off unless you want an effect or to avoid flicker.
Tim Polster December 9th, 2009, 09:42 AM Ryan I do not know your background, but Brian is correct. In the video world, you would normally only change your shutter when you change the framerate unless you want a special effect like a slow shutter blur.
You mainly only adjust the iris and add gain if in extreme lower light conditions for correct exposure.
If this is new to you, I would not sign up to do a wedding before you get a hold on all of this!
Ryan ONeil December 22nd, 2009, 01:25 PM What codecs do HDV come in?
I've messed with AVCHD but which others are they able to come in?
Robert M Wright December 23rd, 2009, 11:52 AM HDV and AVCHD are not the same thing. HDV, by defintion, uses MPEG-2 compression. AVCHD uses MPEG-4/AVC compression (which requires a lot more horsepower, but yields much better quality per bit of data).
Ryan ONeil December 23rd, 2009, 03:16 PM That's helps me some. My question would be: I imported the data into imovie from an fx1 and it downloaded as .mov files. Can HDV be any codec?
Robert M Wright December 23rd, 2009, 03:31 PM No, HDV, by definition, is MPEG-2 encoded video (at 24Mbps CBR for 1080i60).
Ryan ONeil December 26th, 2009, 12:16 PM ah...k. Think I'm getting it. So, once you convert it from mpeg 2, it's no longer HDV. Could it still be HD if I converted it say to a mp4 or mov?
Robert M Wright December 26th, 2009, 12:39 PM Yes. MOV and MP4 are simply containers, like boxes, that hold video and audio streams (encoded with various CODECS - the encoders/decoders for the video and audio streams).
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