Need Help and clairty - Page 2 at DVinfo.net
DV Info Net

Go Back   DV Info Net > High Definition Video Acquisition > General HD (720 / 1080) Acquisition
Register FAQ Today's Posts Buyer's Guides

General HD (720 / 1080) Acquisition
Topics about HD production.

Reply
 
Thread Tools Search this Thread
Old December 22nd, 2012, 12:00 AM   #16
Major Player
 
Join Date: Oct 2009
Location: Reno, NV
Posts: 553
Re: Need Help and clairty

Quote:
Originally Posted by Leon Kolenda View Post
How do you know that none of the bit rates are constant 20 Mbps, it seems to me that if I choose 1080/60I then I can choose HD FX (24) Mbps is this spec not constant?
Yes, but its better to shoot with the highest quality 28 mbps PS mode.
Eric Olson is offline   Reply With Quote
Old December 22nd, 2012, 11:26 AM   #17
Regular Crew
 
Join Date: Nov 2011
Location: Myrtle Beach, SC USA
Posts: 147
Re: Need Help and clairty

So are you saying that if I shoot in the PS mode on my Sony VG-20 (1080/60p) and I render out (PPro CS6)
to their spec, (1080i/29.97 mpeg-2, Constant 20-Mbps Quality -4, Upper Field first), that I won't see a slower playback? I have never done any slow motion or any redering out to a different FPS than what the Original shoot was.
Leon Kolenda is offline   Reply With Quote
Old December 22nd, 2012, 01:11 PM   #18
Inner Circle
 
Join Date: Feb 2007
Location: Apple Valley CA
Posts: 4,874
Re: Need Help and clairty

If you use 60p, it CAN be used for slo-mo, but it does not HAVE to be.

Frames per second, bitrate, and the other specs have nothing to do with playback speed of the clip. They are "industry" ways to express the technical quality of the data in the clip.

What Eric is saying is to capture at the highest quality, edit at the highest quality, THEN when it's time to render it out, you choose the needed settings, and let the NLE convert to the needed output format in the render.

One of the problems here is that you are confusing many of the settings, where they are applicable, and struggling with what they are and how they might affect the video.

Take a little time to google (or just search DVi!) each of the words and get a handle on what they mean, and you'll be in a LOT better shape here... right now all the terms and concepts being thrown around probably seem like gibberish because you don't "speak the lingo"... need to learn the lingo, THEN your queries will either have been answered, or will be easier to answer... so far you're "challenging" the answers or coming to wrong conclusions from an incomplete grasp of the subject matter.

Frames have already been well explained, I think you've got resolution (sort of)...

Bitrate is a bit of a tricky thing - it is how much data is available per second of video playback - less data=lower quality, more data=better quality. There are lower limits, below which your image will look like poo (technical term <wink>), and upper limits beyond which the playback will stutter or freeze as the data rate overloads the buffers in the playback equipment, or exceeds the capabilities of the media.

Bitrates have been increasing with faster processors in cameras and faster computers to edit footage. As your camera will warn you, as you go higher on the bitrate, you limit your media options for playback. Higher bitrates will also make editing more of a challenge if your computer is old or slow... 17Mbps was the "high" setting for many cameras, just 2-3 generations of cameras ago!


Shoot at the highest setting, import into your editing program at the best setting IF your computer can handle it... WHEN you get to rendering the final output, do one render for SD, one for HD, using the specs your broadcasters tell you they need/want, and deliver the files via whatever method they prefer. You should find all or most of the settings either in a preset or a customizable menu when you go to render, learn them as best you can beforehand so you don't have to render too many times while sorting it out.
Dave Blackhurst is offline   Reply With Quote
Old December 22nd, 2012, 11:46 PM   #19
Regular Crew
 
Join Date: Nov 2011
Location: Myrtle Beach, SC USA
Posts: 147
Re: Need Help and clairty

Thanks Dave, that helps a lot.

So far I have what I think is a pretty fast computer, I built it myself.
WIn7 64 Pro, Intel i7-4.0 Ghtz. 24 gigs of DDR3 fast memory, Nvidia GTX460 GPU, Cuda compatible to Adobe software, 1 Gig of GPU Ram, 480mb Corsair SSD drive, used for OS and Apps.
12 Terabyte WD Raid 5 NAS. 1 Terabyte 7200RPM WD Black Caviar for scratch disk. Does not break a sweat.

Oh yes, If you shoot in the 1080/60P which is a 28 Mbps, is that a constant? The Station here's Spec is calling for a 20 Mbps constant.
Leon Kolenda is offline   Reply With Quote
Old January 12th, 2013, 04:24 PM   #20
Major Player
 
Join Date: Oct 2009
Location: Reno, NV
Posts: 553
Re: Need Help and clairty

Quote:
Originally Posted by Leon Kolenda View Post
Oh yes, If you shoot in the 1080/60P which is a 28 Mbps, is that a constant? The Station here's Spec is calling for a 20 Mbps constant.
Suggested workflow:

Shoot 1080/60p 28mbps->Edit->Render 1080/60i 20mbps constant

Alternative workflow:

Shoot 1080/60i 24mpbs->Edit->Render 1080/60i 20mbps constant

Shooting 60p will give more flexibility and quality, but in either case it is the render setting in your video editing software that needs to be 20mbps constant not the camera.
Eric Olson is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK


DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > High Definition Video Acquisition > General HD (720 / 1080) Acquisition


 



All times are GMT -6. The time now is 12:41 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network