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February 24th, 2006, 11:55 PM | #1 |
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Preparation for Broadcast
Hi,
I have to prepare three minutes of footage of an event which will be broadcast by our National Broadcaster. Apparantely it will be converted to Betacam (by them) and prepared for broadcast. I live in PAL land. Is there anything that I should be aware of or take particular note of when preparing this footage for them. For example, should I shoot in HDV or DV (I know that HDV will be letterboxed but this is fast becoming the norm here)? Are there other things that I need to watch out for e.g. bitrates, file formats, etc. etc. I did read a document made available by one of our other broadcasters that specified their requirements but I could not make head or tail of it. In this document things 'required silence' and special timecode and stuff like that were specified (for example). Is it not possible to just deliver stuff on DVD. I mean - when a National or Public Broadcaster broadcasts a movie they surely must use the same DVD that I would use in my home (or do they have special copy). Anyway - this to me has always been first prize - to have some of MY footage actually broadcast - so any advice and technical information would be greatly appreciated. Edit by self: Sorry - I forgot to mention - I am using an FX1E and a VX2100E (and editing with Vegas) - that is why I posted here. Second edit by self: What makes Betacam so special? I mean to say - what are the differences between Betacam and DV? Is that the right way to ask the question? Can you compare the two? Regards, Dale. |
February 25th, 2006, 01:32 AM | #2 |
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Let me get this straight, you are going to broadacst something, and you have no idea what time code, and "required silence," and similar such, is?
I mean, I dont want to point fingers, but it sounds like you are in way over your head. Maybe I can help a little If you live in PAL land, I'm guessing Australia right? And its for TVS? Then you need a Timecode on the film, I think 8 seconds of silence before the film, and 8 seconds of colour bars and that sound tone (name escapes me.) Dont put it on DVD.... I think it is rare that they would accept something like DVD. Put it back on Mini DV tape, or onto Betacam. Its more convenient. If you really want to know, Betacam has always been a broadcasting choice because of its particular quality... It has always been surprior to VHS, and some tape forms now, but its becomming slowly, and I say... Slowly outdated. And broadcasters would rarely spend millions just to change formats as they change. Beta has always been reliable, flexible and of the best quality to date. But no, you cant compare the two. Beta and DV are two mediums created for different purposes. however, I favour Beta, but I'm poor, so Mini DV is the only way to go... You really need to talk to someone who can show you a pre broadcast product. As far as I can help you is just tell you what you need. As far as that, someone is going to have to post an example up. |
February 25th, 2006, 08:53 AM | #3 | |
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Thanks for the reply but maybe I did not explain properly.
I must prepare a three minute edited clip from about four hours of footage of an event. The customer is aware that I will be giving them the edited footage in DV format (.AVI) and they are going to 'have it converted to Betacam' for the broadcast. I just want to know what the technical differences are between what I can produce (DV .AVI) and what will happen (technically) when my footage is converted to Betacam, thats all. I live in South Africa and it will be broadcast by our National Broadcaster (SABC) on one of their channels (I do not know which or when at this stage). I have read some broadcast specification documents of theirs before and yes, your are right, I could not make much sense of them (I did read about the timecodes, silence, tape leaders, etc. etc.). The purpose of my query is so that I can learn about these requirements - I am not actually going to be physically providing anything else but the edited DV footage and I am told that as part of the 'conversion' process all of this will be taken care of by the customer and / or our National Broadcaster. I suppose my questions really should have been: 'Why does DV footage have to be converted to Betacam in order for it to be ready for broadcast'? 'What is the difference between Betacam and DVCam'? Are these just physically different formats or something like that? The reason for this question is that I have read (somewhere on this board as a matter of fact) that you can use DVCam tapes in our FX1's / Z1's (although it was stated that this was done in an emergency). Why is a high bitrate, high quality, MPEG file not good enough? Does a broadcaster play the same DVD movies when broadcast as I have in my home or do they have some 'special' copy of the movie? Just wanting to understand and get ahead! When you say: Quote:
Regards, Dale. |
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February 25th, 2006, 09:04 AM | #4 |
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A lot of broadcasters are asking for a master on BetacamSP simply because of the fact that there whole production is based on that format. From acquiring, editing to archiving.
If you give them a file of your 3 minute movie in the right native codec of your source, your good to go. |
February 25th, 2006, 11:55 AM | #5 | |
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Quote:
-Greg |
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February 25th, 2006, 05:41 PM | #6 |
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but I think thats besides the point.
The broadcast community use Beta anything because it has always been there, ans would cost an arm and a leg just to change formats. Besides, the physical size of some also allow more flexability and consistency as Greg has mentioned. |
February 25th, 2006, 08:58 PM | #7 |
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I doubt the analog formats will be around in the broadcasting industry much longer. They simply won't have a use in a few years, so I wouldn't put to much effort into learning that much about them, unless you have a current need (or are just curious). If the broadcaster will take the material in DV format, and then do whatever they need to do from there for them to be able to broadcast it, I'd leave it at that.
US analog OTA broadcasting gets the plug pulled permanently, in less than three years now! (Feb. 17, 2009) |
February 27th, 2006, 12:07 AM | #8 |
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Good Morning, and thanks for all of the replies.
I suppose for the most part I was just curious - sort of 'what is so great about Betcam?', 'why is it (has it been) the broadcast standard?', 'what makes it superior to DV?, etc. etc. From all of the replies (and looking at various articles on the Internet after posting my original question) I gather the following: It is a 'media reliability' and 'robustness' issue more than anything else? Because Betcam is analogue these issues would be far more important (to avoid tape dropouts and ensure picture quality)? Because it is an analogue format I assume that the volume of 'video data' is far greater per unit of tape (remember capturing analogue video before DV was introduced)? DV is converted to Betcam for broadcast simply because that is the way the broadcaster was initially set up? To simplify things and for want of a better explanation of my understanding there is therefore no difference (from a quality issue) between converting my footage to betacam or, if it were possible, to simply take the RGB output of the FX1, connect it to the broadcast equipment, and press play (actually this would be better as, because the conversion to Betacam is actually a conversion from digital to analogue, the quality of the coverted footage would be largley dependant upon the hardware on which the conversion was done). How am I doing so far? All of this, however, does raise more questions though. I notice things on broadcast television that most 'average viewers' don't even see (and I'm sure that that statement applies to all members of this board)! As an example I see many inserts / programming where the interlacing, for example, is incorrect (the interlace flicker is blatantly obvious). What will happen to my DV footage (which I assume would become 'interlaced, top field first' from 'interlaced, bottom field first' after the digital to analogue conversion i.e. to Betacam)? I also assume that on the footage to be supplied to the broadcaster I would use the Vegas 'broadcast colors' filter or not? I always check my footage on a television monitor. Would it be safe to say that if my footage is visually correct on my television (no interlace flicker for example) it would broadcast fine? In years gone by I seem to remember reading somewhere that the actual resolution of broadcast television is technically much lower than that PAL DV for example i.e. PAL DV is 720 x 576 and broadcast television equates to something like 400 x something? Anybody else ever see this and know the exact figures? Is this true (I cannot find the article anymore)? Why have I read (I think it was somewhere on this forum) that footage shot with the FX1 / Z1 was visually perfect until it was actually broadcast and then it looked 'terrible'? Could it be beause of all of the issues detailed above? Sorry for all the questions but like I said in my first post having MY stuff actually broadcast has always been my end goal and the more that I understand about broadcast requirements the better job I will be able to do. This is my first shot at this and I don't want it to be my last! Regards, Dale. |
February 27th, 2006, 12:52 AM | #9 |
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To answer one question quickly -
Unless I'm mistaken, there is no RGB output from the back of an FX1. You have an S-Video and composite video output, and also a component video output available. Those are all YUV output. The S-Video and composite outs would provide a signal that is inferior for recording to Betacam formats. I suppose you could use the component out, but best to simply give the tape to the broadcaster. They almost assuredly will have the proper equipment to make the best possible conversion. |
February 27th, 2006, 01:20 AM | #10 |
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Hi,
Sorry I mean't Composite not RGB! No it's not that I wanted it done that way it was just to explain my understanding of the information being given to me in this thread. While I'm on the subject DOES anyone have a (small) sample of FX1 HDV or DV that has been prepared for broadcast (which conforms to a broadcast spec with regard to tape leaders, silence, timecodes, etc. etc.) that I can download and have a look at? Thanks, Dale. |
February 27th, 2006, 01:57 AM | #11 |
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The composite signal coming out of the camcorder, is basically the lowest quality signal you could get (ok for VHS, but that's about it).
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February 27th, 2006, 09:00 AM | #12 | |
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Quote:
- Broadcasting a video picture does terrible things to it. Good idea to start from the very best quality you can get. - DVDs aren't actually that good compared to Beta - Colour is much blurrier than the brightness info - A DVD image broadcast would look much blurrier at the end TV set - Also, the blockiness you see on DVDs when things move fast will be made to look even worse once it's at the final TV set. - Beta (SP and DigiBeta) is a standard in broadcast; one format for all, etc - DV decks not really used, because larger Beta cassettes are more robust, no compatibility problems - DV is so finely tuned, Sony adapted it to DVCAM for pro market, still not as good as Beta, though - Small DV tapes are universally hated by VT Operators as they can jam in decks when the rush is on, too darn fiddly! - A tape for broadcast must -- Fit the decks in the broadcast suite (e.g. Beta!) -- Have some bars and tone up front as BetaSP is ANALOGUE and the bars and tone allow the VT Engineer to ensure that the whites are white, the blacks are black, reds are red, blues are blue, and the sounds don't blow your ear drums out because THEIR deck may be set up slightly different from 'YOUR' deck and the test signals like Bars and Tone are industry standard. -- But which bars? 100% or 75%? Which tone? 1KHz or warbling Dolby Tone? At what level if coming from a digital source? is 0db (ANALOGUE) at -12dB or -18dB DIGITAL? The person doing the Beta dub from your AVI will deal with that) ;-) -- Then some black and silence -- Then a clock that counts down to the beginning of the programme --- In olden days, it lasted 40 secs. Now it's usual to do 20 or even just 10 seconds for short stuff. --- The clock should display the title of the clip, its duration (see note on this), and maybe other info such as edit date, version, etc. --- It helps the VT operator if the programme's timecode hits 10:00:00:00 or 01:00:00:00 absolutely bang on the very first frame of your programme, so if you have 1 minute of bars and tone and a 20 second clock, the timecode runs like this Tape plays from start: 09:58:30:00 bars and tone 09:59:30:00 black and silent 09:59:40:00 clock starts counting down from 20 seconds 09:59:57:00 cut to black and silent (just in case somebody cuts in too soon!) 10:00:00:00 programme starts - lets say it runs for 3 mins 30 secs 10:03:30:00 programme ends, last frame freezes for 5 seconds (just in case someone forgets to cut back to studio at the end) 10:03:35:00 Fade to black, continue silence 10:03:55:00 Tape recording ends. Note the duration is 3 mins 30, the 5 sec freeze at the end is ignored. Different stations have different patterns of the above, sometimes with stringent measures of signals on tape, often with special labelling requirements. Check, or have your dubbing facility check. Betacam SP preferred over DV because the way strong colour is handled on DV - it looks blocky and very low resolution. However, in engineering terms, some may argue that DV has an edge over BetaSP, but let the engineers fight that one out. If you have the facilities, you may also wish to explore shooting and editing HDV, then downsizing the final edit to 'DVCPRO50', which gets over the quality problems of DV, and the TECHNICAL quality is very close to Digital Betacam. However, HDV needs to be shot carefully in order to make best use of the format. Do your best job shooting in a format you're comfortable with. :-) Hope this helps. Sorry to repeat on a few items, lack time to make it shorter. :-D |
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February 27th, 2006, 10:30 AM | #13 | ||||
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Good Evening, and WOW - thanks Matt for going to the trouble with that response - more the type of things that I was trying to find out!
If you don't mind I would just like to comment and get a little more clarity on one or two things: Quote:
Quote:
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With regard to audio: Why is it (again mainly with DSTV) that you very often (almost always) get a program whose volume level is X and as soon as there is a program break (like for an ad for example) the volume level is suddenly at Y (and Y just about makes you jump out of your seat). Are these levels not automatically compensated for by the broadcast equipment? Nothing has ever left my shop without being checked and the audio is always normalized to -3dB. Too high for broadcast? Audio track should be Mono, Stereo, or Dobly Digital? Regards, Dale. |
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February 27th, 2006, 12:48 PM | #14 | ||||||
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Quote:
Digital Satellite Broadcast (and Terrestial Digital like the UK's FreeView) appears much better quality because it's component, not composite (well, not exactly, but that's the crux of it) - a form of MPEG2. However, broadcasters squeeze at least 4 digital channels into the space of 1 conventional channel, and that means it's like watching a DVD whose MAXIMUM data rate never goes over 2 Mbits per second. So you get problems with recompressing compressed images, you get poor performance with highly detailed scenes and movement, and so on. What you DON'T want on DBS is highly compressed stuff from MPEG2 streams re-hashed then recompressed. Think about it this way: MPEG 2 is the instant coffee version of a proper brew. Imagine the disgusting mess if you tried to make instant coffee from a pot of... instant coffee. All the 'essential' secret ingredients were removed long ago in the compression, meaning there's no room to add any sparkle or finesse. Quote:
- On a tape format that will not give the station any excuse to complain - From a source that's equal or better to your working format There's no point making an uncompressed delivery version of a DV project, but there's more point in editing DV rushes in an uncompressed environment - if you shoot DV, you can edit in DV but if you're doing colour correction, effects and so on, you're better off in DVCPRO50 or even uncompressed. I use FCP, so I can work in DV until the final output - where I tell FCP the timeline is now to be DVCPRO50 or Uncompressed, and it patiently re-renders everything (all the transitions, effects, colour corrections) within an environment that can take the subtlties I want). The result may only just playable on my PowerBook, but will look great when layed off to DigiBeta. Quote:
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If you're an advertising agency, you tell the director 'I want to sock it to them big and loud' and so the nominal audio level is around -12dB (ha! I've seen -6dB) and all peaks are pumped through a compressor to keep them a hair's breadth from 0dB - just like every CD you purchase. ... And if you're a commercial radio station, you compress the feck out of your output so there is no dip in the relentless stream of noise. It all bubbles along at -6dB so there's no need to 'Touch That Dial' (the Volume dial, apparently). Quote:
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February 27th, 2006, 01:08 PM | #15 |
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Hi,
I can't thank you enough for all of your input - those are all of the things that I really wanted to know about. Of course there are many more questions than answers but for now I at least have an insight into what some of the pitfalls are. Thanks again, Dale. |
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