Macroblocking and HC9 with Nano
 

Hello,

I'm shooting an independent feature next year and I'm thinking of shooting with a Nanoflash to record it in Long GOP, 50 mbit/s MXF files (or possibly 100 mbit/s). It's going to be shot on my Z7U (24p pull down to 60i) and a few POV shots on my HDR-HC9 (60i).

I believe I understand the different possible settings on the Nanoflash. The reason I chose the listed compression, bitrate and file type is because I would like archive the footage on Sony Professional Disks in the proper file system (or as data in 100 mbit/s if needed) (any higher bitrate, storage cost becomes an issue) and I will edit on CS5.

Two Questions:

1) The feature won't have any cinematography too extraordinary or drastic. And I understand that 100 mbit/s is the sweet spot for Long GOP, but has anyone EVER experienced macroblocking at 50 mbit/s? At 100 mbit/s?

2) Has anyone used a HC9 with the Nanoflash before, and can confirm that the signal coming out of the HDMI is uncompressed and usable by the Nanoflash? I can't find that info on this site nor on the web nor in the HC9 manual, concerning the HDMI.

Thank you.

Hi!

1/ MPEG2 4.2.2 @ 50MB/s is a broadcast standard now so I doubt there is macroblocking at this bitrate. However, personnaly, I've chosen a compromise: 80MB/s which is a bit better than 50MB/s and saves you 20% of disk space from 100MB/s.

2/ I had to use the HDMI output of a Sony CX-550 with the Nano with very good results. I think HDMI output delivers real 4.2.2 uncompressed HD. I doubt there have been changes in HDMI output format between HC9 and CX-550. I also used the NanoFlash with a Canon HV20, which is as old as the HC9 I think, and the picture quality from the HDMI output was much more better than HDV.

Thank you.
 

Thank you, Ronan, for taking the time to share your experience. It makes my decision a lot easier.

Sincerely,

William

William,

Macroblocking is visible even at higher bitrates for demanding scenes, and the Nanoflash will help reduce it with higher bitrates. I posted an example (search for Elephant Seals) with breaking ocean waves that showed macroblocking for both 35 MB SxS　and 100 MB Nano. Although you have to search the stills for the macroblocking, it is easier to see on the continuous video.