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Tzedekh

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Posts posted by Tzedekh

  1. 15 hours ago, Vesku said:

    It should work directly with 10bit HDR TV giving the best HDR video possible with GH5 dynamic range. True HDR is 15 stops or more and GH5 is not capable of that.

    I don't understand the point in implementing an HDR mode if it doesn't capture any more than the 12 stops achievable with conventional means. 

  2. ​HDMI cannot send raw data, just video, only SDI carries raw.
    There is a way to get around this by wrapping the raw data into a signal that fools the HDMI protocol into seeing it  as a video feed, but this would require Nikon doing that trick (which is just theory and nobody else ever sent raw over HDMI) plus they would need to produce a dedicated external recorder than can identify, decode and record that signal, there are no external recorder that do it on the market. So no, HDMI is not a possibility.

    ​Actually, Apertus experimented with raw over HDMI when developing the Axiom Beta.

  3. I checked the Fairchild website since they use their sensors in the Pocket and Cinema Camera. The chip mentioned on bmcuser is the LTN4625A, you can find all the info on the website: http://www.fairchildimaging.com/catalog/focal-plane-arrays/scmos/ltn4625a

    It does tick the 4K @ 240 fps box, but it's a 12MP sensor, not a chip with exactly 3840x2160 pixels like Andrew is talking about.

    I'm sure it is the LTN4625A. I think Andrew meant that the new sensor has a 16:9 aspect ratio, as does UHD. The 4,608 x 2,592 resolution represents a 20% oversampling over 3,840 x 2,160.

  4. How can the sensor output 6k video (or even 4k video) when it only has 4.44M active pixels?  That's more like 1080p-class resolution. The only way I can see it outputting 4k video is if it upscales its 2166 vertical lines to 3180, which can't help but look nasty.


    The only thing I can think of is that there are three layers of pixels, each of which has 4.44 MP. The 2,052 x 2,166 array is then cropped to 2,048 x 2,160. Because the pixels are twice as wide as they are tall, the aspect ratio is the 1.89:1 DCI standard. The additional horizontal resolution may be achieved through something like pixel-shifting.
  5. I hate to be a Debbie Downer, but if the LS300's sensor is the AltaSens AL41410C, the dynamic range is theoretically only about 10 stops, and that's with a rolling shutter.
     
    As to whether the the 4K is 4:2:2, I suspect it is. JVC also announced the GW-SP100E remote head camera system, which seems to use the same sensor. Among the specs: "Up to 4K Ultra HD 50/60p recording at 4:2:2 150 Mbps" and "4K single file recording at 150 Mbps." I assume that if the GW-SP100E can record 60p 4:2:2 at 150 Mbps, the LS300, at 24/30p and 150 Mbps, is probably also doing 4:2:2. I suppose the latter spec means that JVC isn't using their goofy process of simultaneously recording to four SD cards, RAID-style, but is recording as a single file.

  6. Only 10-stop of DR, that's not good.

     

    I agree, but in all fairness, it's the same sensor that's in the AJA Cion and the BMD s35 4K cameras. Sadly, there's a paucity (and by that I mean a virtual absence) of off-the-shelf 4K sensors with decent dynamic range. A custom sensor could be designed and fabricated through a company like Alternative Vision, but it would cost two to four million dollars and likely take at least a year, and God only knows how good the results would be. Quality control and yields, yada yada. And then there's all the work that has to be done to write the code that makes the sensor usable.

  7. why cant it send a RAW signal without the breakout box?

     

    Why can't it send a raw signal directly to the XQD cards the same way that the Ursa sends one to its CFast cards? CineForm RAW 4K at 24 fps is typically 50-75 MBps, well within the rating of an XQD card. Higher-speed ones could handle 4K at 60, 96, or even 120 fps (though the FS7 tops out at 60 fps). By the way, CineForm is the basis of SMPTE's newish VC-5 standard.

  8. In terms of specs, what we know is that it will shoot 4K XAVC internally, to XQD cards, which I like, they're fast, inexpensive and reliable media. That's all we know. Though It has an overcrank button as in the FS700 therefore it may be true it will do 180fps internally.

    I don't expect this to be an FS700 successor at all, or an NEX successor of any sort. It's a 4K XDCAM camcorder designed for competing with the C300 broadcast/wedding/doc market. I bet they'll leave 4K raw and 240fps for the FS700 and this will be an entirely separate line. The FS700 is just getting popular now.

     

    In other words, a big sensor and the guts of a Z100 (which does 10-bit, 4:2:2 intraframe XAVC up to 600 Mbps).

  9. It may or may not be, the wording from the RX 10 is "Sony brings out the full potential of Full High Definition (Full HD) movie recording... by utilising every pixel from the image sensor at accelerated speed".   

     

    For the A7s they say this about the video: The world’s first full-frame sensor capable of full pixel readout*1 without pixel binning for movies and 4K*2HDMI video output 

     

    If the RX10 were generating video the same way the A7s did I think they'd be bragging about it, but they're not. I think they're just using every pixel in the binning process on the RX10.

     

    I actually misspoke. As reported by EOSHD, on the RX10 the entire 5,472 x 3,080 sensor is read out at 60 fps then downsampled by the Bionz X processor to HD. To me, that means no binning or line skipping. Maybe the RX10 couldn't handle 4K recording or output without overheatng.

  10. It already does 4K internal, it comes off the sensor as 4K and is debayered, all the hard work done and sent to HDMI rather than compressed and sent to the card. 4K compression is trivial. Mobile phones do it. I don't believe the overheating theory at all... The biggest heat management issue in the A7S comes from the sensor and that is already doing 4K even for 1080p. It's probably more work for the image processor to downsample the 4K output to 1080p than it is to compress the 4K and write it to the SD card. I think they are saving the feature for future models.

     

    This is equally true of the Sony RX10 -- it samples natively at 4Kp60. It then sends the image to the Bionz X processor.

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