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androidlad

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Posts posted by androidlad

  1. 5 minutes ago, OliKMIA said:

    The Mavic 2 Zoom and Pro, and Mavic Air 1 are also very noisy in the shadows. The Mavic 2 Pro is 1 inch sensor. The previous generation of drone didn't show this type of noise. Apparently it has something to do with the Processor in these drones when DJI went the cheap route and skipped the ambarella processor. Which they corrected on the Mavic Mini but I haven't tried this drone.
    All this noise wasn't there on the Phantom series. The Phantom 3  also had great 4k at 60mbps whereas the Mavic 1 was a disaster in 4k. The compression artifacts were so bad on the first mavic that I sold it after one week. All that suggest an image processing issue.

    https://dronedj.com/2019/11/27/ambarella-processor-dji-mavic-mini-mavic-3-pro/

     

    Those drones with 1" sensor have 12bit ADC, so the noise level will be noticeably better.

    Mavic 2 Pro is a special case because the 4K is either heavily subsampled from 5.5K full width, or 1:1 sampled from the centre. Both of them amplify noise level.

  2. Just now, sanveer said:

    Any particular reason it is 10-bit. I remember a lot of smaller sensors are 12-bit. 

    Mobile phone CMOS sensors are generally 10bit ADC only, for power consumption and speed.

  3. 1 hour ago, User said:

    And to export what about Frame Rate and Pixel Aspect Ratio? Somehow I'd like to ditch 29.97 for 23.976.

    The original files are: Image Size: 720 x 480, Frame Rate: 29.97, Pixel Aspect Ratio: 0.9091

    *Edit. I just read the Toutube/ Vimeo prefers square pixels.

    From an academic point of view, what you are doing is essentially "digital curation" (well, a ghetto version).

    You would want to preserve all of the "significant properties" of the digital objects and only "transform" the intended property, which in this case, is the resolution.

    That means square pixel, HD with original 4:3 aspect ratio (960x720 or 1440x1080, depending on how good the upscaling algorithm is). The frame rate should also remain unchanged.

  4. On current sub 1" CMOS sensors like the IMX586 used on MAVIC Air 2, the ADC operates at only 10bit, this is the reason why even at base ISO, in both photo and video mode, anything below middle grey is covered in noise.

  5. 2 hours ago, currensheldon said:

    I'm guessing Canon is more interested in selling lenses than anything else. Of course, they want to sell cameras, but it would make sense that the margins are WAY higher on lenses than on cameras. EF becoming the standard for so long definitely helped and if the RF-Mount becomes the new mirrorless mount that everyone without their own mount uses (Red, Z-Cam, Black Magic, etc), then I'm sure Canon would be very happy with that. 

    So Canon gets compressed raw (though only to about 5:1) and Red gets mounts and sensor help. Wonder what else is going on. 

    RED may have helped Canon develop the DIGIC X Processor, and other yet to be announced ones 😉

  6. 4 hours ago, Kisaha said:

    I noticed that the new remote seems a lot more practical than the owful - older - design. That's a good thing I guess.

    This is clearly their amateur line, while we are waiting obviously a new Mavic series, and probably keep the existing ones with reduced price. Probably the Mavic 2 zoom near 999, the Mavic 2 Pro for 1.199 and the new ones at 1.249 and 1.499. Something like that.

    I am wondering what's the size difference between the two..

    Also consider Autel EVO II series, they are rapidly catching up and are pushing frequent firmware updates.

  7. Another thing is that with the switch to the new DJI Fly app, there's no longer the option to adjust the sharpening (and contrast, saturation). So in video mode you're stuck with the over-sharpened edge halo.

  8. 3 hours ago, Patrick B. said:

    @cardinalallen good information to consider.  I overlooked the comment about the C300 seeing more into the shadows.  So even though the SNR1 rating was lower than the C500, it may be that you can actually eke out more in post.  Interesting point about the color channels in highlights.  I’ll be interested in seeing how it handles this.

    Also, I noticed the Mavic Air 2 does some kind of HDR processing where different pixels are mapped to different exposures, similar to what DGO is doing.  Are other cameras doing this with Sony sensors?  That sounds like a useful feature for high resolution sensors that I didn’t consider before.  I’ve heard talk about quad Bayer sensors where blocks of pixels can become pseudo bigger pixels and record better low light at lower resolutions like we see in new camera phones.  But I never considered that high resolution sensors could actually record two exposures in lower resolution and essentially turn what is usually a negative sensor attribute for video into a positive.

    The HDR video mode on Mavic Air 2 uses the DOL-HDR feature on the newer Sony sensors, it's very similar to dual gain but the two readout are not completely simultaneous (a few miliseconds apart), and requires 2 ADC for high and low gain, which halves the max frame rate and doubles the rolling shutter.

  9. 9 hours ago, cardinalallen said:

    I think there are a few caveats with this test.

    First, it's using a pre-production camera.

    Second, it's using XF-AVC. The author argues that with a log curve like CLog2, there won't be any difference between that and raw. Personally, I suspect it's a bit more complicated than that, and depends significantly on the implementation. I've heard for example that the Alexa ekes out a tiny bit more DR with arriraw than with Prores. 

    Third, and related to the first and second point, Clog2 is only rated for 15-stops DR. Whilst under the above measurement the C300 Mk III only has 12.8 stops, it technically is rated by Canon at 16-stops. This matters because presumably some work has to happen on Canon's side to figure out how to distribute its DR within the Clog2 gamma. 

    In the comments, the author writes the following: 

    Given that it's a pre-production camera, there could well be some tweaking that needs to be done on this front.

    Fourth, it says nothing of the actual roll-off. This is ultimately the crucial question. Canon said that the DGO would allow for higher saturation in highlights, which is crucial to that smooth roll-off; what happens at present is that different colour channels clip at different rates and thus you end up with colour posterisation in the highlights. Roll-off always looks so much better in black-and-white for this reason.

    This test might prove to be accurate with the production model, but I think we should treat it with caution.

    The only caveat I agree with is the fact that it's a pre-production camera.

    Remember it was a standardised lab test, Alexa was tested in ProRes using the same methodology, so it's completely fair to test C300 MK III with XF-AVC. With Alexa being the benchmark, there's something to compare to, so if want to take into account DR distribution in specific log curves, highlight roll-off etc., then the Alexa DR would change too, so maybe instead of 14 vs. 12.8, you could get 15 vs. 13.8. Again remember it's a standardised test, the DR numbers are all relative to the benchmark, we can't look at them on their own.

  10. 6 minutes ago, thebrothersthre3 said:

    I believe it was 2k 200mbps

    Just shot some tests at 2k 100mbps Long GOP, no issues in the shadows. Really weirded out wtf is this 

     

    It's the infamous F-log banding/macro-blocking, discussed before.

  11. 49 minutes ago, Kisaha said:

    what's your take Vs the Mavic 2 Pro? I have barely used mine, I wouldn't like to sell it already..

    Obviously the sensor is bigger in 2 Pro, and more sensors I guess.. I do not mind the size, I believe it is just perfect, not Phantom-like, which it was too much, but feels more substantial than the Air 2 design (I guess).

    Image quality wise, in daylight Air 2 will be very similar, if not slight better than the Pro. Of course it won't be as good in low light, and it doesn't have 10bit and D-log M.

  12. 43 minutes ago, sanveer said:

    It does seem to say that it has a few HDR modes. Hopefully, some of them are for video too. 34mins flight time(?), 68kms speed(?), and 10kms travel range(?).

    Yeah HDR photos, video and panorama (multi-exposure blending)

    34min flight time, 68km/h max speed, 10km max signal range.

  13. 2 minutes ago, IronFilm said:

    Apple just licenses out the codec. Which is quite different to the RED patents, which block people from doing internal compressed raw. Oh hang on, the MAVO Edge doesn't do great compression than 5:1 ProResRAW? Is that still light enough compression that it isn't covered by RED's patents?

    https://support.apple.com/en-gb/HT200321#proresraw

    Not yet in Apple's list but should be there by the time the camera ships.

  14. 51 minutes ago, Andrew Reid said:

    In most of those examples above it is just the orange & teal grading in action.

    Although doing nuanced warm and cool shades in one frame is indeed the hallmark of a nice image, in my opinion.

    Nuanced tones like cyan and good white balance are one of the traits of the 1D C and what separated it form just merely a "very good" 4K camera at the time like the Samsung NX1.

    So it isn't about 10bit.

    It's the white balance, colour science, and sensor.

     

    It's not quite that simple. You can't add what the camera doesn't capture.

    You can change hues and biases but if the baseline capture is flawed it gives you a TON of time consuming work to do AND never looks as good as a better file.

    Meant to type "can't" on the phone. 😁

    you can't just add cyan to any footage make them look high end.

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