DSTV HD worth it?

[smarterthinking]

That's my personal experience comparing the same movie on 1080p24 Bluray to DSTV's 1080i50 (25 fps frame doubled). The bitrate is lower than Bluray though (according to the port throughput on a DVB-IP HDPVR2P), so up close you can notice more artifacting in dark detail.

From a motion handling perspective, unfortunately there is no 1080p50 content out there to compare to DSTV's 1080i50, but superficially I don't notice the kind of picture corruption/tearing you'd expect from an unprocessed interlaced picture on my decent/modern TV.

As far as the resolution goes, the locally shot stuff using MC's own HD cameras (esp in studio) is too sharp & clear on a 1080p display to be 720p.

This dark noise or artifacts that you see is a general digital imaging problem as is the colour blue. It all actually starts with the digital camera the footage is shot on and oh yes also down to what compression ratios the footage is captured at, chip size and codec the cameras shoots. Compression and codecs...

I personally have shot 4:4:4 uncompressed 1080p50 and it looks amazing on a studio monitor, actually perhaps to clear and digital looking. I have also shot compressed 720p50 on a canon 5D Mk2, which also looks OK. The canon actually handles the dark areas very well due to it shooting a negative and processing a transversal image, pushing your noise or artifacts into your highlights making them a lot less noticeable..(very clever)

Once footage has been graded and pushed out to 1080p25 I have had advertising agencies battle to tell the difference when cutting between the 2. In its RAW format you can defiantly tell the difference, but once graded, desaturated ect. its not easy.

The studio cameras MC use are Sony cameras which actually have a 1/3 size chip or sensor, much like the sony pro-sumer EX3 but the difference come in with information acquisition. The EX3 compresses the file storing it to a card and the studio cameras signals are fed uncompressed to a control room which have uncompressed Sony SR1 type digital deck recorders. First generation uncompressed is best... (One recorded not including cameras is close on R800 000).

Most source material bought or received is compressed so you loose the details in the image. If one was to deliver RAW footage a 30 second commercial would use about 220Gig of space, so for convenience all material delivers to a broadcasters will have to be compressed to their specific file spec. The compression is usually worked out and defined with something called rate–distortion theory which gives an analytical expression for how much compression can be achieved and is acceptable for the specific broadcaster. I am almost sure DSTV are not working with the rate-distortion theory hence why some films look so crappy and others so good....

 

[smarterthinking]

Useless info but good to know.... 720p50 - 1280x720 - 50 frames/s - 921.6 Mbit/s
1080i25 - 1920x1080 - 25 frames/s (50 half frames) - 1036.8 Mbit/s