Muz wrote:
Hi Guys
Have a question surrounding DVD authoring.  A friend is getting some classic Pakistani movies converted from the original BetaCam masters to DVD for screening at a film festival in the UK (exact date TBD).  While the movies can be screened from the BetaCam tapes - there is a need to add subtitles to them so it looks like one option is going to be converting the movies to DVD and adding the sub-titles to the disc.
While locating DVD conversion firms we have found that the services offered vary greatly ... will need a quality transfer as potentially the disc will be projected on to a big screen.  Anyway - I know bits and pieces about DVD conversions ... but just wanted to check a couple of things with the Zulmi gurus!
I asked about progressive transfers, and the answer that I got was that they can do progressive - but normally they do constant bit rate transfers!  I really don't know what that means!
Also - we have a choice in getting the discs made up as single or dual layered (single layered will mean splitting the movies - but the movies are already split over two tapes anyway!)
I think that the betacams were created in the US - so it will be an NTSC transfer.  I think that we should avoid converting to Pal.  Just in case we have to convert to Pal for any reason - is there any way to do a clean Pal to NTSC conversion and avoid the ghosting effect?
Finally - does any one have any experience with adding sub-titles to an already authored disc?  Is it an easy thing to do and is any software available to help us do this?
I really want to ensure that these DVD masters are created well ... the rights holder of the movies may want to release them to the market soon ... so hopefully this will mean that we get at least 6 good quality DVDs to watch! 

Thanks in advance for your help!
Muz.
- avoid constant bit rate unless it's very high, but then you might run out of space on the DVD with long films.
- Dual layer DVD, of course. Single layer can't support high compression quality for longer films.
- If the master is NTSC with correct pulldown put that pulldown on the DVD and the picture will be progressive from good DVD players with progressive option. Storing progressively on the DVD saves bits, but the shop really must be able to do this properly or they will do more damage than good.
- NO PAL conversions! And if PAL is not avoidable the NTSC must be made progressive first via reverse 2:3 pulldown, then resampled to PAL and put on the DVD with 4% speedup. No frame averaging! No analogue steps, all in the digital domain.
- I have my doubts that the Betacam stuff is any good, but if it is a nice DVD can be made. Not for cheap, though.