The GH4 can be preordered in Finland at Topshot.
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Andrew from EosHD “believes” you can get 1080p 10bit 4:4:4 with your GH4:
Actually the theory is 8bit 4:2:0 4K material from this camera can be taken through a workflow in post that converts it to 10bit 4:4:4 1080p – with all the smoother tonality, better colour and workflow advantages that format brings. This is a big leap for 1080p based on the much more expensive C300 which only does 8bit 4:2:2.
The way this works is quite technical but it essentially amounts to using the extra pixels present in the 4K files to rebuild the lost colour information. Neighbouring pixels are summed to create a super pixel with a greater bit depth and better sampling. It requires a lot of processing power and a finishing codec good enough to store the extra colour data (10bit 4:4:4, with CineForm and ProRes being suitable choices) which is why the camera doesn’t do it internally. It does require a transcoding step in post but the increase in quality over the 8bit internal 1080p codec will be marked. The message is clear. Even if you’re working in 1080p, shoot 4K on the GH4 if you want the best quality.
Well this would be really big news if real!
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Some more GH4 tidbits:
David: “As came across another GH4 article, this is interesting as it shows the difference between the cropped GH4 4K and Super 16 film size, it isn’t hugely different so I reckon a few S16 lenses might work on it? Exciting news I think for C mount fans! http://filmmakermagazine.com/84315-with-4k-gh4-panasonic-comes-out-swinging/”
Japanese CP+ Hands-on video on Youtube.
Anonymous soruce: “Real final GH4 price will be between 1 300 € and 1 400 € for Europe and $ 1,499 for Usa. no more. Availability in April.”
51 Responses
Here is the same theory also with a demonstration test:
http://www.slashcam.de/artikel/Grundlagen/4K—Von-RAW-bis-4-2-0.html
Didn’t take a genious to figure that out.
At twice the resolution you have full color sampling for each FullHD pixel.
The increase from 8bit to 10bit is based on 4x the precision, since you’ll have 4x the pixels to start with.
The 10 bit is a bit of a fake benefit. (And, the original poster who calls doing this “quite technical” is just wrong.) In 4:2:0, you have a full resolution luma plane, and the color planes are half resolution in both dimensions. (1/4 the total samples.) In order to make 4:4:4 1080p out of material that is 4:2:0 at twice the resolution, you just take the UV planes and present them unaltered, and then scale the Y plane down to half resolution. (Being exactly half resolution, a simple box filter where you average the four pixels together will be just fine.) In the Y plane, you can get values in between the 8 bit values, hence it appears to be “10 bit.” (Though, there are many circumstances in which you will absolutely see a difference vs. “true” 10 bit, because you are looking at post-quantised data.) But, in the UV planes, you will absolutely not get any real benefit to going past 8 bits. So, in 1 of 3 planes, you get a slight benefit by treating it as 10 bit in some cases. That’s absolutely not the same thing as would be recorded by a 10 bit camera. Anybody who says otherwise is thinking in RGB about YUV data and misinterpreting the results. OTOH, yes, it really is “true” 4:4:4 when scaled down at 1080p. You have a sample of Y, U, and V at every pixel location. That’s simple math.
(Source: I’ve written plenty of software that works directly with the Y and UV planes of 4:2:0 video for nice reconstruction of RGB without hard blocky egdes.)
Thanks for the explanation.
@ Will
I’d be interested in your opinion: Theoretically, might there be an advantage to downscaling Blackmagic Production Camera “4K” UHD (3840 x 2160) ProRes HQ footage (10-bit 4:2:2 at up to 884 megabits/sec. for 30p) … to … 1080p ProRes 4444 (12-bit at up to 1,326 megabits/sec. for 30p), color-wise?
Just wondering if there’s potential color benefits in the above scenario, similar to downscaling GH4 4K to 1080p? Thanks in advance.
Yes, there is a slight benefit, but 10 bit 4:2:2 is already quite good data. The whole conversation about the GH- series is only because they are recording 8 bit 4:2:0, so people are trying to figure out any tricks they can do to give themselves a little breathing room going into grading to push the colors around. Since 4:2:2 has two luma samples for every color sample, it’s already got more color than the eye can see. 4:2:0 is four luma samples for every color sample, which is basically right at “just good enough for the eye,” but no wasted data if you want to move things around a lot in the grade.
Thanks for the follow-up. So, with the BMPC-4K footage, downscaling (as described above) might be of some beneficial for chromakey or other effects in post?
“Real final GH4 price will be between 1 300 € and 1 400 € for Europe and $ 1,499 for Usa. no more. Availability in April.”…if true Panasonic have hit a home run, hope they can keep up with production 🙂
+1
Anonymous soruce: “Real final GH4 price will be between 1 300 € and 1 400 € for Europe and $ 1,499 for Usa. no more. Availability in April.”
That would be too awesome! Hopefully, Hong Kong prices will be in line with the figures quoted above. With the extra $500 burning a hole in my pocket, I can buy even more gear…
Panasonic GH4 on wedding photo shoot http://www.youtube.com/watch?v=UYU4aEx_Wso who would thought, eh?
+1 . . . GREAT Video! Thanks for sharing!
What an extremely pretty girl in this video!!! Wonder if she comes with the GH4?
What are you, 12?
Look at what’s holding your camera: that is the only friend you’ll ever get in bed with you (I hope it’s the tripod)
You seem angry that I had something nice to say about the GH4, the video, the girl and a “ThumbsUp!” for our fellow 43Rumors member “YouDidntDidYou”.
I am sorry if any of that offends your sensibilities.
My god. Is it seriously that difficult to shoot a video with good audio now a days?
those B&W shots are nice
the colour ones ?…dont like them personaly but I am not pro … so who cares
I would, it’s nothing special.
The bride is pretty though.
The _skin_ especially looks awful in that video (in the actual video clips in the edit, not the photo stills in the edit).
Hopefully GH4 can record skin that looks much, much better than that!
4:4:4 can be a little overrated – we are not that sensitive to color resolution unless it’s at the edge of a highly saturated patch. Of course, it’s never a bad thing to have more data to work with.
No it’s not.
I can see clear benefits even from 4:2:2 when you have well defined and saturated red subjects. Do a simple test: take any video you have and, superimpose some red text. Then export to h264 with 4:2:0 sub sampling and compare that to the same video exported in 4:2:2.
There is stairing and jagging in 4:2:0. Now the difference from 4:2:2 to 4:4:4 isn’t as telling.
…Well, Stupig specifically said that “4:4:4 can be overrated”, not 4:2:2. :T
Yes, I should have said that the biggest jump in IQ is probably more noticeable from 4:2:0 to 4:2:2.
“Japanese CP+ Hands-on video on Youtube.”
I was standing behind that guy waiting for GH4 to touch myself 10min and this crappy video is the result?
Still hopeful that IBIS can be implemented by the next iteration. Sad that Olympus can do it in video, and GX7 can do it in photo, but no such luck at all for Panny’s flagship model. I will wait instead for the GH5.
It’s pretty telling that Olympus, who don’t invest much in video, go all out on sensor stabilization, while Panasonic, which has found a niche in video, has excluded it from its new flagship. It’s probably a tradeoff, likely having to do with heat dissapation. They probably had to forgo stabilization to be able to keep things cool enough for unlimited 4K and super fast bursts.
I guess the positive way around that is that if you’re a 1080p shooter, shoot 4k and wider than normal and then crop and use software stabilization. You won’t have to worry about loss of detail since you’re outputting 1080p from a 4k stream.
If only. You’ll have rolling shutter (although supposedly reduced with this sensor) and lose some focus handheld. That said Panasonic lenses are stabilized and the GH3 body is very stable in the hand, easy to hold steady in my opinion. But people clamoring for buttery smooth handhel 4K video with no rigging in a sub-$1500 hybrid camera might be asking for a tad much now don’t you think?
You can hardly call it rocket science that downsampling a lesser color space picture into lower res will improve color resolution for the remaining luma info.
Since the color info is allready downsampled by a factor of 2 in both axis, downsampling the luma from 4k to HD brings the luma down to the resolution of the chroma signals. This does not improve the color resolution but reduces luma res.
Exactly.
And the 8bit to 10bit increase is just a consequence of having 4x the precision in luma.
Noob question, does this affect dynamic range?
All sensor tech involves dynamic range. So, since the GH4 is using a new(ish) sensor, the answer is yes.
The rumor is that it’s the same sensor that’s in the GM1 and GX7, but the GH4 has a fatter data pipe to handle the 4K… Anyway, you can get an idea how the GH4 handles dynamic range by checking out those two other cams.
Or wait a few weeks as the video examples start hitting the web.
Thanks!
The downscaling to get “10 bit” luma doesn’t improve dynamic range. It gives somewhat better sampling of the existing range, but that’s not necessarily the same thing as actually having more range. That said, you’ll reduce noise in the blacks from the supersampling, so you will have slightly better useful range if you are exposing for the top end, compared to straight 8 bit 1080p with the same per pixel noise profile.
You seem angry that I had something nice to say about the GH4, the video, the girl and a “ThumbsUp!” for our fellow 43Rumors member “YouDidntDidYou”.
I am sorry if any of that offends your sensibilities.
just saw panasonics lens road map (or lack of)
is it me or is there a disconnect between panys cameras department and
there lens department
camares seem to be going some where lens seen to just stop
i know a lot of pepole will be useing this camera with
manuel glass but why make a show about the new af if
they dont make the lens to go with it
I don’t get your point. Olympus and Panasonic have introduced so many new lenses in 2013 and announced in 2014-2015 it is hard to keep count. What other camera company has done more?
my point is that there is still big holes in the MFT lens line up
that are not being filled
for me the bigs draw back to MFT is lack of lens (supertelephot)
It’s just you.
> but why make a show about the new af if they dont make the lens to go with it
DFD is said to work with the previously released lenses. (Hm… 20mm AF performance test please?)
Otherwise, what lenses are you missing? They do not have tele primes, but otherwise Panny’s lens catalog is pretty well rounded.
i dont agree that the MFT lens line up is that well rounded
at the momnet 100mm reach is about it with AF
What are you talking about? For one thing, ALL MFT lenses from Panasonic and Olympus have AF. For another, Panasonic offer a 45-150mm, a 45-175mm, a 45-200mm, and a 100-300mm, while Olympus offers a 40-150mm, a 75-300mm, and improved versions of both. The longest focal length currently available on MFT with AF is 300mm, not 100mm.
I don’t know how you got that information wrong. o_o
I guess he only counts the primes and X zooms – which is kind of silly.
Everyone keeps missing the part where you need to buy about $4500 worth of accessories to record 4k. That makes the Blackmagic Production camera at $3000 look much more attractive.
No, you don’t need any additional accessories to record 4K video.
At all.
You need a SD card that has a high enough data rate to handle the bandwidth, that’s it. Not sure why you would think it needs accessories to record 4k?
That accessory unit you’re alluding to is for recording a professional compression of the 4K signal and allowing other direct pro inputs required for more advanced productions.
Nothing surprising for a high rez down convert to lower rez & looks better. But I’ll be damn if you can convert the old DV 4:2:0 format into digiBeta 4:2:2 10bit quality.
Park Cameras in Burgess Hill are advertising GH4 body only for £2,000
http://www.parkcameras.com/27466/Panasonic-LUMIX-DMC-GH4-Body-Only.html
only for £2,000…
That was (body only) (for £2,000).
A proper bargain, there may be two people from this forum buying it to shoot their shoes.
The math doesn’t *exactly* work out. It would be more accurate to say that by downsampling you get 4:4:4 1080p with 9-bit luma and 8-bit chroma (since each luma sample is drawn from 4 8-bit samples, yielding a 1-bit noise-floor improvement, and each chroma sample is drawn from 1 8-bit sample).
But that’s ignoring the effect of compression, which probably makes the gains less than that. On the whole I’d say you can expect a downsampled 1080p result that’s slightly crisper than what you’d get out of a native 1080p cam, but don’t expect any kind of miracle.
here is a small video to explain chroma subsampling and how we can get 1080p 444 from 4K 420 http://www.youtube.com/watch?v=kIf9h2Gkm_U