C300 Mk II White papers

[Barry Goyette]

Haven't gone through all of these yet, but a few takeaways are:

-- Canon's characterization of the camera as an extension and improvement of the HD/2K capabilities of the C300 with the addition of "constrained" 4k features.

-- 14bit processing for white balance, and Chromatic Aberration correction prior to compression.

-- 120 FPS mode uses a 1k (540p) sample and then up samples to 2k. (not sure exactly what this means as their 4 frame sample RGBG is giving some extra resolution -- i.e. 4k is sampled at 1080p RGBG and then reassembled into 4k, so we might be seeing more than 500 lines with this technique...experts weigh in).

-- The use of the word "definitive" in reference to the 15 stop DR claim (any one who knows Larry Thorpe knows he doesn't over-state things.)

-- Luma S/N Ratio at all ISO's up to 51,200 bests the C300 at base iso. (phenomenal)

https://usa.canon.com/CUSA/assets/ap...c300markii.pdf

http://usa.canon.com/CUSA/assets/app...c300markii.pdf

http://usa.canon.com/CUSA/assets/app...c300markii.pdf

[Barry Goyette]

A couple of other new things out there I just noticed:

the Recording features white paper lists a 550 Mbps version of XF-AVC for 120 FPS (which I don't think had been mentioned by canon before -- hard to tell as it looks like they are updating the "features" section of the product page as we speak.)

and they've posted the instruction manual for the camera...all 223 pages of it...

http://gdlp01.c-wss.com/gds/8/030001...-mk2-im-en.pdf

[Paul Chiappini]

Thanks for the link to manual. A couple of questions that I had were answered.

1. Proxy recording to SD card can be done without also recording to CFast 2 cards. CFast slots must be empty.

2. 4K recording is done at 410 Mbps. There is no option for a lesser bitrate.

[Barry Goyette]

4k Monitoring. So the only option canon offers is a 4k Raw output over their Rec and Mon terminals, which apparently can only be utilized directly by monitors like it's $20-30K reference displays. I guess this info has been out there for a bit, but the manual helped me wrap my head halfway around it. I'm wondering what other options there are for monitoring in 4k? Perhaps passing through an Odyssey 7q+ or Shogun?

I'd love to hear from the experts. This is a little out of my league as I've mostly relied on camera mounted monitor/recorders, and I think 4k is going to require more critical evaluation on set.

[Jim Martin]

Great find Barry!

[Gary Huff]

This is definitely a mistake. It should have 4K monitoring out of HDMI. Hell, the GH4 can do that!

[Jim Martin]

Lets not jump to conclusions now.....

[Barry Goyette]

The manual is explicit that there is only 2k/HD over HDMI and SDI. The only 4k "output" is raw (via the REC and MON terminals). This was reported by Newsshooter and others at NAB. I don't think it's a mistake. Again, if you read the "performance enhancements" white paper, it's clear that Canon still sees the focus of this camera as a 2k/HD workhorse with the 4k box "checked". During the various c300 demo's I've seen and heard about, the reps haven't been able to get the 4k monitoring to work, except at NAB and Cinegear when the reference displays were attached. I think we now know why.

I just hope there is a reasonably priced solution for 4k monitoring in the near future. As much as I'd love a $20k monitor to go with my $16k camera...:-)

[Gary Huff]

It needs to output over HDMI so that if you need to deliver ProRes 4K you can do it and record XF AVC internally as well. Shogun or Odyssey or Pix-5 would be great for this.

You can do raw->4K ProRes in some respects, but that would negate the Pix right off the bat, so that removes it as a potential option.

[Mark Dobson]

Originally Posted by Paul Chiappini

Thanks for the link to manual. A couple of questions that I had were answered.

2. 4K recording is done at 410 Mbps. There is no option for a lesser bitrate.

That's strange as when I went to a product demo at Elstree Studios I was told there were 2 bitrate options for 4K, 1 at 410 Mbs and one at somewhere around 300 Mbs.

The only option for recording at a lower bitrate in 4K will be to record externally.

I've no doubt that it all looks spectacular but it really eats up the storage requirements. The Sony FS7 offers a wider range of bitrate options with the lowest being XAVC-I mode: 4K 25P VBR, bit rate 250Mbps, MPEG-4 H.264/AVC.

Maybe more options will appear in subsequent firmware updates although we all know not to expect anything specific that's not written on the tin!

[Gary Huff]

Originally Posted by Mark Dobson

Maybe more options will appear in subsequent firmware updates although we all know not to expect anything specific that's not written on the tin!

And even so, how long did it take the C300 Mark I to get WideDR or have it's color tint fixed?

[Barry Goyette]

Just looking at the readout charts and some of the language in the manual, if there was something that could easily be implemented in firmware it would be 4k/60p. The way the sensor is being read for both HD/2k and 4K is essentially the same (at 60p), and it doesn't really seem like there's a bottle neck on the processing side either, so it really comes down to codec and data rate downstream. It's interesting in the white paper that 120fps gets a 550 mbps version of XF AVC that 4k doesn't...and I'm curious if this may be something that is pushing the limits of CFAST right now (with the assumption that 120fps might be used in short bursts versus just letting the camera run). I don't know...Mitch Gross sure seemed to think they would be able to get 60P out of it on the Odyssey back at NAB..(I know this has changed)..but it seems like the flpping of the switch on this feature at this point is more of a "decision" than a limitation of the hardware. We'll see.

I'm still curious if there will be an inexpensive approach to 4k monitoring with this camera or not.

[Andree Markefors]

Originally Posted by Barry Goyette

-- 120 FPS mode uses a 1k (540p) sample and then up samples to 2k. (not sure exactly what this means as their 4 frame sample RGBG is giving some extra resolution -- i.e. 4k is sampled at 1080p RGBG and then reassembled into 4k, so we might be seeing more than 500 lines with this technique...experts weigh in).

It's important do distinguish 'pixels' (as in the final image frame size) and 'photo sites' (as in a "pixel" on the sensor).

A 4k Bayer sensor has 4096x2160 photosites, but as you know, thanks to the Bayer pattern, those photosites are divided into green (x2), blue and red 'pixels'. That is, in a 4k image, if we isolate the color groups we have four 2048x1080 individual lattices/frames.

In the C300 mkII each color lattice is then interpolated up to 4096x2160 pixels—that is the 'gaps' in the lattice are filled (averaged I guess) so that we end up with four 4096x2160 (8,8MP) frames: Red, Green1, Green2, Blue.

When Larry talks about 1024x540 frames for 120fps he is talking about the discreet color channel pixels in the Bayer pattern. That is: 1024x540 pixels each of Blue and Red and actually two separate 1024x540 lattices of Green.

In relation to the output frame it is still a full 2k without any skipping or stuff like that.

I hope this makes sense.

[Douglas Call]

Originally Posted by Barry Goyette

The manual is explicit that there is only 2k/HD over HDMI and SDI. The only 4k "output" is raw (via the REC and MON terminals). I just hope there is a reasonably priced solution for 4k monitoring in the near future. As much as I'd love a $20k monitor to go with my $16k camera...:-)

Do you think the Blackmagic Design Smartview 17" 4K monitor would be compatible with the C300? I t has 4K monitor ins.

[Gary Huff]

Originally Posted by Douglas Call

Do you think the Blackmagic Design Smartview 17" 4K monitor would be compatible with the C300? I t has 4K monitor ins.

It will not be compatible.