Odyssey7Q + FS700 - 4K Modes
- Thread starter Dan Keaton
- Start date
chromeboy007
Well-known member
brazzam
Well-known member
Correct me if I'm wrong, but we're just discussing whether or not to record 256 vertical lines... There won't be any quality differences between the two modes. QuadHD would simply be "cropping" the image to a 16:9 ratio, right?
Personally, (and I already voted so don't count my vote twice) I can easily set my NLE to conform my footage into a 16:9 project, so I don't foresee workflow issues on taking a 4K image and fitting it in a QuadHD project, if QuadHD is what I was delivering. This is why I voted for 4K first - I can easily get QuadHD from the 4K file if that's what I need, but it doesn't work the other way.
Personally, (and I already voted so don't count my vote twice) I can easily set my NLE to conform my footage into a 16:9 project, so I don't foresee workflow issues on taking a 4K image and fitting it in a QuadHD project, if QuadHD is what I was delivering. This is why I voted for 4K first - I can easily get QuadHD from the 4K file if that's what I need, but it doesn't work the other way.
paulcurtis
Veteran
Full 4K.
This begs the question, the crop factor must be different then between the modes. So with the standard HD i wonder if the 700 is downsampling a smaller portion of the sensor (QuadHD) and therefore the full 4K will change the crop slightly and use pixels we've never seen before?
In which case then cropping QuadHD out of the 4K photo sites will yield exactly the same result as recording quadHD in the first place?
So surely full HD is a no brainer?
cheers
Paul
This begs the question, the crop factor must be different then between the modes. So with the standard HD i wonder if the 700 is downsampling a smaller portion of the sensor (QuadHD) and therefore the full 4K will change the crop slightly and use pixels we've never seen before?
In which case then cropping QuadHD out of the 4K photo sites will yield exactly the same result as recording quadHD in the first place?
So surely full HD is a no brainer?
cheers
Paul
stefanhuberfilms
Veteran
would be good to know before making any decisions! +1
The FS700 has an 11.6M Bayer array sensor. That works out to ~4540x2554 elements if the sensor is exactly 16:9 (http://www.wolframalpha.com/input/?i=11600000+=+x*y,+x/y+=+16/9). The question is, what is the actual resolution provided by Sony in 4K mode RAW? If Sony provides full 4K (or more), and the Oddysey performs a high-quality deBayer and resample to 3.8K (quad HD), with no measurable loss in resolution on a chart, it makes sense to support quad HD vs. 4K (more efficient). How could this be possible? 4.5K isn't large enough to sample 4K without aliasing (8K is needed); getting max deBayer resolution is expensive to compute, and will not yield an alias-free image unless sampled at 2x the output resolution (again, for 4K that's 8K (F65)).
More detail from Alistair Chapman: http://www.xdcam-user.com/2011/01/when-is-4k-really-4k-bayer-sensors-and-resolution/
More detail from Alistair Chapman: http://www.xdcam-user.com/2011/01/when-is-4k-really-4k-bayer-sensors-and-resolution/
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paulcurtis
Veteran
This would need clarifying. The stills mode from the 700 produces QuadHD res (3840 × 2160). I was under the impression that not all the 11.6M pixels are RGB, meaning that 4540x2554 may not work, that's assuming RGB pixels.
The output from the Sony recorder is 4K (4096x2160)
The only way i can see it happening is that 4K (4096) must be using a slightly wider area of the sensor which has previously been read as 3840 across for 1080 HD. So these 2K and 4K modes are using more of the sensor in a wider aspect ration (1.89)
The O7 cannot resample to QuadHD because the aspect ratio would be wrong, it would crop the pixels either side.
So again, we can crop out QuadHD but not the other way around.
cheers
Paul
brazzam
Well-known member
I very much agree. Dan, how are the engineers planning to obtain these QuadHD recordings? By simply cropping the 4K image down to 3840 or are they going to resample the 4K signal?
paulcurtis
Veteran
Hi Alan,
It would have to be a crop because the aspect ratios are different. It's just the horizontal pixels that differ, the vertical is 2160 in both cases. The 4K mode is slightly wider than QuadHD.
As Dan said originally, more for drama and features but i don't see how anyone would loose by not recording the full 4K and either cropping it for QuadHD, it's something that every NLE can do without breaking a sweat. But the 4K allows us to reposition slightly, stabilise slightly and make slightly better 2:35 extractions. 4K is win win for everyone
cheers
Paul
cuervo
Veteran
i find it absolutely astonishing how much buzz (aka bandwidth) this entire subject of the FS400 and O7Q generates. C-D asks for a simple user poll, choice A or B, and the discussions go ballistic. Considering that whichever choice is chosen by C-D, the second choice will be released fairly soon, I don't understand the furor it creates in this community. Oh well, I'd rather be out shooting than pixel-peeping.
nyvz
Veteran
I vote for 4k.
QHD is not so bad, but better to record as much as possible. The way I see it, you can frame/protect for 16:9 if you have to have 16:9 and I think in most NLE's if you drop 4K in a QHD timeline, it will automatically center the image and crop the sides. And for other cases where filling the 16:9 frame is not as critical, for most content these days a little letterboxing in 16:9 deliverables is no big deal as people are used to seeing content with various degrees of letterboxing for artistic/cinematic effect anyway.
4K makes the most sense to me since 16:9 is the tallest aspect ratio we're likely to shoot for these days, so the extra horizontal real estate will be good to have for all other common aspect ratios (1.85, 1.9, 2.4, etc). 4K will maximize FOV and resolution.
QHD is not so bad, but better to record as much as possible. The way I see it, you can frame/protect for 16:9 if you have to have 16:9 and I think in most NLE's if you drop 4K in a QHD timeline, it will automatically center the image and crop the sides. And for other cases where filling the 16:9 frame is not as critical, for most content these days a little letterboxing in 16:9 deliverables is no big deal as people are used to seeing content with various degrees of letterboxing for artistic/cinematic effect anyway.
4K makes the most sense to me since 16:9 is the tallest aspect ratio we're likely to shoot for these days, so the extra horizontal real estate will be good to have for all other common aspect ratios (1.85, 1.9, 2.4, etc). 4K will maximize FOV and resolution.
blackdogdylan
Active member
4K.
paulcurtis
Veteran
Well now look what you've done, you're going to start another thread about the FS400.
It's very rare that a manufacturer has such a direct relationship and i guess we all want our say and clarifications...
cheers
Paul
brazzam
Well-known member
I'm sorry if my seeking further information on the topic is seen as "ballistic" or "furor"... I simply would have thought many people would have opted for 4K in this thread, as the difference was (to me) minimal and I didn't foresee too many workflow issues for cropping 4K-to-QuadHD in an NLE.
However, when others started suggesting their reasoning for QuadHD, I wondered if I wasn't fully understanding the difference in the two modes and was seeking clarification.
Many of us are excited about this new product and how it might enhance our shoot workflows. I currently only own a 4" monitor and shoot on SD cards internally and am waiting on the 7Q to enhance both of these aspects of my production arsenal. I find myself perfectly able to both do my job/go on plenty of shoots as well as seek further information for products I am interested in investing in. And, thanks for CD and Dan's patience, I actually have the opportunity to interact with those making this product - which is a really fun and added bonus.