60Mbps 4K leaving me unimpressed

[Paul Anderegg]

So, with lots of light, 1080p FHD exports from my X70 4K raw footage looks ULTRA SHARP, and pretty. At the high gains I shoot normally though, 24-33db, the 60Mbps codec simply isn't capable of handling the noise, and marco-blocking runs rampant. A little grading makes things like red fire trucks lit by red LED's simply swim in little wiggling blocks.

So for now, I guess I will be sticking to HD, and continuing to wait for my $300 rebate on my 4K upgrade. It is also notable that 4K to 720p is not a pretty downconvert. Also, on FCPX 10.2.2, X70 60Mbps 4K video HARD CLIPS at 100IRE. If you skim the timeline, you will be able to look at 100-109IRE on the waveform, but the moment you stop, it hard clips again. If you want 100-109IRE usable in FCPX, you need to batch transcode to XAVC L or i using Catalyst Browse, which when ingested into FCPX will give you access to 100-109. :-)

A few 4K high gain still frame grabs.....click for full UHD resolution......everything wide open iris.

Paul

[Jeff Krepner]

I have similar feelings from a recent corporate video I shot in 4K. In hindsight I should have done 1080, but that is my fault for not testing more. The skew on some footage was worse than I thought and ruined a few takes and the darker scenes had more noise than I feel like I get with similar settings and environments in 1080. I oversold myself on the need to re-crop into 4K footage. I also missed face detection that doesn't work in 4K. All user error, but food for thought.

Edit: I think for slower daytime filming I would certainly shoot 4K since there are so many extra options in editing, and I think the idea is to get the camera in the right mode for a given scene.

Jeff

[Bruce Watson]

Originally Posted by Paul Anderegg

So, with lots of light, 1080p FHD exports from my X70 4K raw footage looks ULTRA SHARP, and pretty. At the high gains I shoot normally though, 24-33db, the 60Mbps codec simply isn't capable of handling the noise, and marco-blocking runs rampant. A little grading makes things like red fire trucks lit by red LED's simply swim in little wiggling blocks.

No doubt true. Neither the small photosites needed for 4k, nor the short exposures allowed by 60p, are good fits with low light. You'd be better served, probably, by a 1080p camera, and shooting at 1080p30.
The bigger photosites can give you better sensitivity which you need, and the lower frame rate will let you open up a stop which you also need. And you can convert 1080p30 to 720p60 as needed. True, you won't get the crisper motion that 60p might provide, but for your work it's hardly needed. Those police cars in your shots aren't moving, so the higher frame rate is a moot point. If you were filming a basketball game... but then you'd have lights.

[Paul Anderegg]

I shoot for an ABC station, so we are among the few that actually BROADCAST 60p content to viewers. I always set shutter to 1/30 when subject matter isn't moving, but true 60p 1/60 makes things like talking lips look more pleasing and natural. :-)

I am looking at the new XA35 from Canon. When my station converts to Zixi from Teradek, my Sony's built in live streaming will become non-valid, so this opens up other possibilities. I really love the compact form factor of the X70, and it can take a LOT of gain in HD mode with 20MP downsampling taking the noise out.

Other factors that make the X70 a go to camera for me, is it's ability to spit out 720p60 HD-SDI, no matter what record mode you are in. 720, 1080, 4K, doesn't matter, it will output 720p60 if so selected, which makes live shots possible. My PXW-X180 and X200, as well as my work JVC HM890, will NOT allow this, and will change SDI output specs as you change record formats.

Paul

[Paul Anderegg]

Well, the Canon is OFF my list.........the only 720 mode it has is 720p30 at 4Mbps, and has no 60p HD-SDI output that would be compatible with my live transmission equipment which doesn't accept 1080p60 signals.

Sad too, as except for the lack of 4K and live streaming seems like a much better camera all around, same low light capability.

Paul

[Bruce Watson]

Originally Posted by Paul Anderegg

I shoot for an ABC station, so we are among the few that actually BROADCAST 60p content to viewers. I always set shutter to 1/30 when subject matter isn't moving, but true 60p 1/60 makes things like talking lips look more pleasing and natural. :-)

Perhaps true, but it still leaves you choosing the motion "purity" or the noise. You can have one, you can't have both. And I suspect that shooting at 30p and converting to 60p (which effectively is just a 2:1 pulldown, or is that 1:2? whatever, you know what I mean) might give you better results. After all people accept perfectly well the look of "talking lips" (<- I like that phrase; I might steal it) from 24p at the movies, or from the other stations that are broadcasting 1080p30.

Bottom line is, why guess when you can know? Give it a try, if it sucks then don't do it any more.

[Paul Anderegg]

It's not so much the frame rate as it is the shutter speed. When in 60p mode, unless there is enough motion going on in the frame, I stay at 1/30 shutter at night, then switch to 1/60 when needed. I've once in a while shot interviews with very low light at 1/30 shutter, and I really don't like the lip blurring compared to 1/60 60p, looks "wrong". :)

Going to experiment with ingesting 4K to ProRes using Catalyst Browse tonight. Unfortunately, that only allows 1080p, but will allow me to retain 100-109IRE and makes grading and NLE stabilization faster. Would ProRes Proxy 1080p30 be enough for 4K 60Mbps footage?

Paul