5 Replies Latest reply on Jul 27, 2009 8:47 PM by Jim_Simon

    Is this true?  BD formats

    commalot

      If my AVCHD footage is shot in full HD at 30P I won't be able to burn to BD-R without changing it to Interlaced footage first.    I read this in a thread about acceptable BR files.

        • 1. Re: Is this true?  BD formats
          Harm Millaard Level 7

          That is correct. But that is no disadvantage and the quality of your shots will not be deteriorated at all.

           

          30 FPS can easily be displayed at 60i or 60 fields. Frame 1 will result in fields 1 and 2, which are identical (apart from the fact that one field is UFF and the otrher field is LFF), frame 2 will result in fields 3 and 4, frame 3 will result in fields 5 and 6 and so on. In interlaced footage field 1 and 2 can be different, but not with material shot progressive, where each pair of fields will be the same.

          • 2. Re: Is this true?  BD formats
            commalot Level 1

            Harm Millaard wrote:

             

            Frame 1 will result in fields 1 and 2, which are identical (apart from the fact that one field is UFF and the otrher field is LFF), frame 2 will result in fields 3 and 4, frame 3 will result in fields 5 and 6 and so on.

            Seems like it might studder a bit with that process. It would essentially be 15 frames per second. Or do I have that wrong. Maybe better just to shoot 60i for BD purposes unless you want to go 24P.

            • 3. Re: Is this true?  BD formats
              Harm Millaard Level 7

              I'm in PAL country, so for me there is no choice other than 50i. I personally never understood the whole hype about shooting progressive when displayed on an interlaced TV and the argument that it gives a 'filmic look'. It gives a studdering look, but unless you have a camera with at least 1/2" or larger sensors, a Letus with prime lenses for the much needed DOF and a $ 5-10K lighting kit you will only achieve the studders, not the filmic look. In addition you need dolly shots and a crane. Let's not forget that film, shot on celluloid at 24 fps, is displayed with a frequency of 48 half images. You can consider that as a kind of interlacing.

               

              The second thing against progressive is that both film and video must be highly dynamic and that often entails lots of movement where the studdering look is emphasized and interlaced has a definite advantage.

               

              In your case I would go for 60i instead of 30P.

              • 4. Re: Is this true?  BD formats
                the_wine_snob Level 9

                Here is a useful CHART, by Jeff Bellune.

                 

                Also, the Encore BD sub-forum is a useful source of knowlege.

                 

                Good luck,

                 

                Hunt

                • 5. Re: Is this true?  BD formats
                  Jim_Simon Level 8
                  Let's not forget that film, shot on celluloid at 24 fps, is displayed with a frequency of 48 half images. You can consider that as a kind of interlacing.

                   

                  That is incorrect.  Film is often projected at 48 fps, but each whole frame is simply shown twice.  There is nothing analogous to interlacing in film.