1080 60i vs 30p

[Jack Zhang]

There we go Alister. All points (but especially that last point) can't be more true.

There is a difference between progressive and interlaced chroma. As an example, I recently recorded AVC-Intra 100 (10bit 4:2:2) on a HPX300 at 1/30 shutter in 60i (basically Psf) and I instantly noticed blockier reds compared to true progressive footage.

[Gints Klimanis]

Originally Posted by Jack Zhang

30p works better with web based destination content since it's progressive scanning. If you shoot in 60i for the web, you either have to de-interlace by discarding 540 lines or blend the 2 fields together and lower the resolution (There are good de-interlacers out there, but that's not the point.)

A good de-interlacer is the point. If motion in a scene is predictable and sampled adequately, a good deinterlacer will create decent 60p from 60i with minor loss of vertical resolution. Video cards and modern TVs are employing adaptive interlacing to achieve higher frame rates. I'm wondering why Sony doesn't include a good deinterlacer in Sony Vegas. Are there any de-interlacers for sale? Can't a great de-interlacer run on a GPU?

[Gints Klimanis]

Originally Posted by Luc De Wandel

It's all a matter of taste, of course, but I don't like the 'choppy' aspect of progressive footage. Probably I'm just old fashioned, because the trend seems to be in favour of progressive.

Choppy is primarily from 24 fps or 30 fps displayed at 60 fps, but that is the case for any film. Other than lower temporal resolution, 24p should not look choppy on a 120 fps monitor or TV.

[Gints Klimanis]

Originally Posted by Doug Jensen

There is almost zero content being produced for broadcast TV anymore (outside of sports) at 60i. 30P is the norm for broadcast HD television in the US. 60i acquisition is outdated and, in my opinion, looks terrible.

The large majority of cable TV channels broadcast 720p60, including National Geographic. I've worked on nearly 30 sets (talent side), and the only US broadcaster that shot in progressive was ESPN. Everyone else shot in 1080i60, be it with higher end Sony in combination with lower-end Sony Z1s. What's even stranger was a master tape delivered to NatGeo was 1080i60 , not even the broadcast format. My last gig was in 2008. Has everything changed so much since then?

[Doug Jensen]

Yes. Just watch TV. Unless you're watching sports, you're generally not watching interlaced.
2008 was a lifetime ago.

[Jack Zhang]

Originally Posted by Gints Klimanis

Are there any de-interlacers for sale? Can't a great de-interlacer run on a GPU?

They exist on the majority of GPUs for sale, and they pretty much do it in real-time. Compressor is also pretty good, but be careful of low motion on objects with high detail. Compressor's de-interlacer doesn't de-interlace low motion in highly detailed scenes so combing will still happen in that case.

For true post-production hardware, the Snell & Wilcox Alchemist is a VERY good de-interlacer. If you want to filmize 50i into 25p, that leaves zero combing.

[Gints Klimanis]

Thanks, Jack. I was looking for a Sony Vegas Deinterlacing plug-in. I use the Mike Crash and Yadif plugins for deinterlacing, but I would gladly pay for one that is optimized for a modern CPU or GPU. I'm inspired to do that optimization myself, but you know how that goes ...

[Jack Zhang]

Originally Posted by Gints Klimanis

Thanks, Jack. I was looking for a Sony Vegas Deinterlacing plug-in. I use the Mike Crash and Yadif plugins for deinterlacing, but I would gladly pay for one that is optimized for a modern CPU or GPU. I'm inspired to do that optimization myself, but you know how that goes ...

I would DNxHD render 1080i and go through Handbrake. That is optimized for modern CPUs.