25mbs vs 50mbs video files???

[BobFoster]

I haven't quite wrapped my head around the reqirements for 25 mbs video and 50 mbs video. 50mbs HD video is clearly sharper than 25 mbs HD video in all examples that I have seen of the exact same scenes. DV and DVCAM are recorded at 25mbs and our Cassie equipment edits the files as 25mbs. Am I on track so far? Some cameras such as the Sony EX series and DSLR cameras also have the capability to record to flash cards at 50mbs. Our Cassies series III can ingest the footage and edit the files. Are the files dumbed down to 25 mbs during the loading process or are they retained at 50 mbs?? Next, what determines the mbs?? If I use any HD high resolution camera and firewire it to a 50 mbs recorder, do I have true 50 mbs files? Or, are the files similar to loading SD footage into an HD project? Nice but not true HD. Inquiring minds want to know.

[SYLRENAUD]

Incredibly good questions Bob !! I wonder myself.
I have DSLR footage which is 40mpbs & I own a XF300 which shoots at 50mpbs I am very happy with the results I get with both camera although the XF is even too sharp
I have to tweak the camera setting to turn down the Sharpness a bit so that when it ends up burned on a DVD from Arabesk it plays without any "shimmering" when very fine details are involved.
The footage from the 5d/7d when burned to DVD looks outstanding... clients even think its a Blu-ray when they first see it

Now for the weird part I exported a XF300 Mpeg2 file to MM with the mpeg checked _OFF_ & then went into MM.
When I checked the info on the file it reads in the low 30mpbs ??? so I am head scratching like you are... not sure.
It seems like there are more details on the XF300 when I watch the raw files on my MAC than in my S-4100 with HD monitor. (monitor is 720p maybe thats why ?).
(BTW this is the clearest camera I have ever worked with even though I prefer the "look/texture" of HDSLR better)

Syl

[Volker]

When you import HD footage into the CassieIII system, all files are converted into an I-frame-only stream with a data rate of approx. 60 MBit/sec which is really good. When you output to DVD, you won't benefit from the whole MBit-hocus-pocus any longer because you are heavily downconverting the images.
Exporting to Media Manager without having MPEG conversion turned on, is the only way to maintain the quality you saw during editing

[BobFoster]

Here's an interesting item that will record .m2t files at 50MBS. http://tinyurl.com/5rjuelw
I understand 4.2.2 vs 4.2.0 is also a large factor in video quality, however that info is rarely given in equipment specs. Looks like this unit would be compatible with Series III editors and not a bad price at $999.99 for acqusition. Here's the URL that designates the various recording formats and bit rates.
http://tinyurl.com/4s7jvm5

[LouBruno]

I do most of my editing in 50Mps. The specs. also state on the camera that there is 4:2:2 color sampling-twice that of HDV. Bogart imports fine.

Here is the situation though: When we make an AVCHD via ARABESK, the bit rate reads 17Mps. I suppose, as in the past, it is always a good idea to start with the highest quality material. But, sometimes I wonder. Truthfully, I can't tell any difference between 50Mps vs. 25Mps. in the finished AVCHD ARABESK product. However, I do see a difference in cameras. The Canon lens seems to have a better crispness than my HVR-270 displayed. Color is also better. But, don't forget, the SONY HVR was HDV. Like Syl, I have to lower the sharpness level on the Canon camera.

So, I have a few technical questions that maybe can be answered:

1) Does the 50Mps really produce a better quality once compressed to AVCHD?

2) Am I better off using the 50Mps for exportation to the internet or am I losing bit rates from Media Manager?

3)Does leaving the MPEG box unchecked (for higher quality) still result in the loss of audio or dropouts at times with .MXF files?

4) How can I export .MXF files w/o converting to another format?

5). Do we retain the 4:2:2 color spacing/sampling in the finished project?

6)Lastly, How can I save my Storyboard in the BOGART project area without converting to a lesser format size such as HDV or MTS?

Inquiring minds want to know.

[JBrooks]

This is a big deal with me. I think MS should develop a Bogart version that will handle the 50mbp and 4:2:2: clor space. I have mentioned this many times. It would only make our great systems that much more competitive and meet the broadcast standard specs. I know it would require a special super fast hard drive and some software /hardware tweaking , but I bet with Linux, it is very doable. lets push for R&D please.

Joel

[LouBruno]

Added #5. Thanks. I will try to get the answers. These are advanced questions relating to the newer cameras. However, .MXF files with the increased bit rates will be the norm shortly. HDV looks like it is gone, along with tape. That's a bummer, because I still feel tape is a better choice for original material and archiving.

This is a big deal with me. I think MS should develop a Bogart version that will handle the 50mbp and 4:2:2: clor space. I have mentioned this many times. It would only make our great systems that much more competitive and meet the broadcast standard specs. I know it would require a special super fast hard drive and some software /hardware tweaking , but I bet with Linux, it is very doable. lets push for R&D please.

Joel