View Full Version : The definition of "HD", the definition of "24p", the definition of "Filmlike"
Shannon Rawls January 4th, 2006, 03:41 PM *sticky*
Shannon's Definition of an "HD" Camera: A High Definition Camera is defined as a camera that records and delivers you an image that meets or exceeds 1280x720 lines of video resolution on the recorded tape. Examples of popular modern day cameras that meet this "HD" definition are:
1. Sony F750/F900/F950/FX1/Z1/HC1/A1
2. Panasonic Varicam/HVX-200
3. Canon XL-H1
4. JVC HD1/HD10/HD100
Each one of the above cameras has the capability to deliver you a resolution that meets or exceeds 1280x720 lines of resolution ready for editing.
(it does not matter how it achieves it)
Shannon's Definition of a "24p" Camera: A 24P Camera is defined as a camera that records and delivers you an image that is 24 frames per second and each one of those 24 frames are progressive on the recorded tape. Examples of popular modern day cameras that meet this "24p" definition are:
1. Sony F900/F950
2. Panasonic DVX100/SDX900/Varicam/HVX-200
3. Canon XL2/XL-H1
4. JVC HD100
Each one of the above cameras has the capability to deliver you 24 progressive images per second recorded to tape ready for editing.
(it does not matter how it achieves it)
Shannon's Definition of a "Filmlike" Camera: A Filmlike Camera is defined as a camera that records 24 frames per second and each one of those 24 frames are progressive on the recorded tape. The marching cadence of each of the 24 frames are evenly spaced to mimic the same speed and distance of a real-live film camera (i.e. Panavision or Arri) with similar shutter speeds and motion blending. Examples of popular modern day cameras that meet this "Filmlike" definition are:
1. Sony F900/F950
2. Panasonic DVX100/SDX900/Varicam/HVX-200
3. Canon XL2/XL-H1
4. JVC HD100
Each one of the above cameras has the capability to deliver you a Filmlike picture recorded to tape ready for editing.
(it does not matter how it achieves it)
I hope this helps anyone who may have had questions or doubts regarding the honest meaning of these acronyms, abbreviations & terms.
Keith Wakeham January 4th, 2006, 09:26 PM (it does not matter how it achieves it)
I do slightly disagree with this. If I have a qvga camera that uses bicubic uprezzing to get 1920x1080 @ 30fps. Does my uprezzed 320x240 count as HD in your books. I don't think it would, even if it was the best qvga ever. Same goes for your 24p argument. If I take interlaced and call it progressive because I made it go to tape saying it is progressive, don't think it counts.
Now does HVX count as HD, sure. Does canon's H1 24F count as 24p, why not. What matters in the end is if your going for high res and a 24 frame a second look that you get it, which is what I think your point is. However I think that, yes, it doesn't matter how it achieve - it within reason.
I think you can break down HD a little further and simpler. Anything HD is essentially based around a 74.25 Mhz clock. That is how SMPTE defines it pretty much. Anything that is less is not hd, anything greater is likely to expensive to talk about anyway.
Heath McKnight January 4th, 2006, 09:48 PM As I've heard before, tell your DP what film looks like and the DP will make it look like that.
hwm
Shannon Rawls January 4th, 2006, 09:49 PM Well Keith,
I think your mixing THE DEFINITION OF A THING with THE QUALITY OF A THING.
This post is strictly addressing the definition of these terms. So if your QVGA camera can "RECORD" natively-brand new out of the box-all by itself with no post production assistance or computer software tweaks, 1920x1080 motion pictures @ 30 frames per second, then YES, it is by definition a HD camera.
Now will the picture SUCKS BIG TIME? well, of course, and nobody will use it for production, but that doesnt' change the definition of the camera.
We have to be mindful not to mix up the 'quality' of a camera with the 'definition' of a camera. And this is why I say (it does not matter how it achieves it). I have no care in the world how many pixels the HVX-200 CCD sensors have. I could care less if they were little 320x240 webcam sensors! if the final picture is 1280x720 recorded to my tape ready for me to edit and the image knocks the boots off any other camera out there...then that's a HIGH DEFINITION camera as far as I'm concerned.
- ShannonRawls.com
Heath McKnight January 4th, 2006, 10:36 PM Sure, HD is wonderful, but you and I both know that it takes a bit more practice to make good HD images. HD doesn't always mean good images. The user "decides" it with their experience level and practice.
Heath
Keith Wakeham January 5th, 2006, 11:27 AM I get your point a bit clearer now Shannon. I am mixing up definition and quality as it is almost expected to go hand in hand, but doesn't have to.
I'm an engineering student so I'm worse than most people about being hard on electronics and the signal processing. Because of this I mostly believe that numbers are the only way to truely be objective. Watching something is subjective and ultimately the true test.
For the film makers out their Shannons definitions above are right. I once heard of a music producer who said something to these regards: I've heard to many well recorded bad songs and not enough badly recorded good songs. Well, I've seen to many bad movies that look great and seldom seen good movies that are bad quality.
Some like me that will likely be a life time member of SMPTE, I play a numbers game.
Mark Grant January 5th, 2006, 11:50 AM A Filmlike Camera is defined as a camera that records 24 frames per second and each one of those 24 frames are progressive on the recorded tape.
Shooting 24fps is about the least important part of a real filmlike camera: far more important is the contrast range and logarithmic response.
Heath McKnight January 5th, 2006, 11:56 AM I think a film-like camera is one that can also get shallow DOF without too much hassle via its lenses, has a good shutter (even the DVX100 can't do a 1/48 shutter) and more. 24p is one part of a film-like look, IMHO.
heath
Barry Green January 5th, 2006, 01:49 PM (even the DVX100 can't do a 1/48 shutter)
Of course it can. The default is 1/50, but you can go in the synchro-scan menu and change it to 1/48.0 if you prefer.
Heath McKnight January 5th, 2006, 02:03 PM Barry,
D'oh, I forgot about that. Too much time with the Z1.
heath
Alex Horvath January 5th, 2006, 02:10 PM This discussion brings me to another point, while Iīm preferring Marks statement about the contrast range and the dynamic. 24fps isnīt the magic to make filmlike movies.
I just saw the movie "narnia" with a 2kDLP Digitalprojection in a cinema (another change of paradigma - no FILM projector!).
I donīt know if the movie was produced by Film or Video.
The picture was overall nice, bright and clean almost sterile but it never came to a "Film"like feeling. Why? I donīt know, but maybe a Filmprojector is a part what makes a Film a true FILM?
So, while we are struggling to get "filmlike" movies, the cinemas are going to go the opposite way, bringing in VIDEOprojectors (and going the satellite-route with compressed movies) and dispose the FILMprojectors.
Interesting days, indeed!
alex
William Hohauser January 6th, 2006, 05:08 PM Frame rate imparts some of the "film" mystique. The lower the frame rate the more "dreamy" the motion and therefore the content becomes. Music video producers know this and see how Peter Jackson uses a low frame rate to give a "nightmare" quality to some of his action scenes in King Kong or Lord of the Rings.
Douglas Trumball (effect director for 2001, Bladerunner, etc.) has spent years researching the effect frame rate has on the audience. His ShowScan technique (I think that's the name) utilizes 60fps film. He incorporates this into the amusement rides he constructs in Las Vegas and elsewhere. The high frame rate has the effect of making the fantastic imagery seem more "real" to the audience sitting in the ride. He would use an even higher frame rate if it wasn't beyond the capacities of the film stock to withstand the repeated wear.
Heath McKnight January 6th, 2006, 05:18 PM 24p=narrative in the world; Japan I understand is more 60i. Then again, our soap operas and some old TV shows (as my fiancee watches Golden Girls, then Cosby Show, those come to mind) are 60i.
heath
William Hohauser January 6th, 2006, 10:11 PM There is a BBC comedy show called "Red Dwarf" that first ran over a decade ago. When it was shown on PBS here it was standard 25i PAL quality BBC video production. The show was funny and I would catch it in repeats over the years.
Cut to two years ago. BBC America is now on my cable system and Red Dwarf is no longer available to the local PBS stations. Well no problem I'll watch it on BBC America. Wait what's this? The show has been "film-look"ed! It was interesting how the comedy timing was actually different with that missing frame and the softer, grainy look. Or maybe I was used to the show with a video look.
The video look with it's frame rate implies a live performance. 24f is slightly set off from reality, not that that's bad, it's very useful for narrative storytelling. In the past Japan, England and many other countries used video more often for dramatic shows for budgetary reasons. If the show was good and the production was well done it didn't make a difference. But everyone is switching to 24p. Why? Because the shows seem that more dramatic in that frame rate. Also try to shoot an action scene in 60i. Everthing seems to slow down! It also easier to fake a fight in 24f or a car chase.
I happen to like 60i HD when it's shots of wildlife or vistas. DiscoveryHD is the best looking HD channel out there for my money.
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