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androidlad

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Posts posted by androidlad

  1. 9 hours ago, Andrew Reid said:

    I would like to see the image in HDR 24p mode with that dual conversion gain enabled. Probably quite nice. Is low light still challenging with global shutter? The Blackmagic Production Camera 4K had a lot of ciruits on the front side taking up room. These are not BSI Sony chips are they?

    No, that sensor is from CMOSIS. Sony only introduced BSI to its global shutter sensors in the very recent 4th gen Pregius S.

    Even with BSI, the memory node still takes up some space on the photosite, plus the reason Sony went BSI is to further shrink pixel pitch, so it cancels out each other.

    With dual conversion gain, the readout noise doubles and it's already quite high at 2.1e-, so I don't think low light sensitivity will be any good.

    The ultimate global shutter sensor design would be pixel-parallel ADC (one ADC per pixel), but it's still in very early stages of R&D.

  2. sonypregwall.jpg

    ūüĎČhttps://thinklucid.com/tech-briefs/sony-4th-generation-pregius-s/

    This is a very well-written article with nicely made charts on the evolution of Sony Pregius S global shutter sensors. I highly recommend a read.

    FYI, ZCAM E2G uses the 2nd gen 1" IMX267, and from user feedback, the image quality is poor.

    Bear in mind that Pregius S sensors are intended for industrial use,ūüĎČ they are never optimised for pure photographic image quality. Across the four generations, their imaging performance (dynamic range, sensitivity etc.) remain largely unchanged, while increasing pixel count.

    However it's worth noting that 4th gen introduced dual ADC (Dual Conversion Gain) on-chip HDR mode which could potentially provide a more usable image for creative work. As this mode halves the maximum framerate, only the high speed version of the sensors can output video framerate at 30P in HDR mode, it's considerably more expensive than the standard speed variant therefore it's a another hurdle for consumer use.

  3. 39 minutes ago, ade towell said:

    Wondering if the 1.29 crop you are able to turn on for all modes is a digital zoom or if there is no quality hit from filming normal aps-c? Be a useful tele extension for all lenses if so

    There's a slight but noticeable quality drop in 4K in 1.29 crop mode in terms of sharpness and moire, because it's oversampling from 4.8K, compared to 6.2K in normal mode (up to 30P).

  4. 11 minutes ago, thebrothersthre3 said:

    The S1H in 6k H265 200mbps was measured at 12.7 stops. A measurement should be taken using prores RAW. I am sure highlights clip at the same point as indicated in that article. However Prores RAW is going to have nosier shadows then H265 internal. That is going to mean a drop in the dynamic range measurement. 

    Highlight roll off isn't really an issue with RAW as you can make the highlights roll off anyway you want. I'd think you'll see a much thicker image coming out of the Pocket 6k as its using 12 bit log which is closer to 16 bit unlike Panasonic's linear 12 bit prores RAW. 

    BMD's 12bit log encoded RAW is simply a container format, the sensor readout on the Pocket 6K is 12bit linear, it does not become thicker when put into a different container.

    While ARRI's 12bit log encoded RAW is derived from 14bit linear readout, now that's real thick.

  5. The best software stabilisation is achieved by using gyroscope data and calibrating/compensating for rolling shutter.

    Steady XP does all of that and I think it's better than any EIS or IBIS, and it does not have that gimbal floaty look.

     

  6. 15 minutes ago, Andrew Reid said:

    Here it seems like an editing choice in the video. A purposeful chop / skip.

    Until I try this camera myself it is tricky for me to know what other people's shakey hands are doing ūüėā

    IBIS can only do so much.

    Fuji has past good form with IBIS. Sony's is really weak, compared to my Fuji X-H1.

    Yes I plan to pair it with a Baby Hypergonar!

    Works on a Super 35mm frame at 55mm.

    I'd like Fuji to add a firmware update for 4:3 shooting, up to 60p. Max res.

    Sensor is capable of it.

    Anamorphic mode should be 6:5 like Pocket 6K, to go up to 60P, the sensor needs to be cropped to 3728 x 3020.

    https://www.arri.com/en/learn-help/learn-help-camera-system/frequently-asked-questions/alexa-sxt-faq/why-6-5-i-thought-you-needed-4-3-for-anamorphic--41676

  7. 21 minutes ago, TheBoogieKnight said:

    II don't think this is true. You can't get more dynamic range from a 12 bit readout than 12 bits although you can get more *perceived* dynamic range if you start off with more bits and add dither. This is what happens in the audio industry (I worked/lectured in Music Tech for many years). But it actually reduces the true dynamic range, it's just that you can hear (or see in a camera) below the noise floor due to the dithering removing  quantisation distortion.

    Cameras don't just read the sensor then dump the data straight to the cards, do they?

    Noise floor can be lowered by noise reduction.

  8. 3 hours ago, HockeyFan12 said:

    How do you get more than 12 stops of dynamic range from a 12 bit ADC readout? Isn't this impossible by definition? Wouldn't there by a hard ceiling of 12 stops from a 12 bit ADC? See the depreview link above.

    My issues are that I don't know why Cinema5D uses SNR=2 as the noise floor or why they place the first wedge of the Xyla chart below clipping. SNR=2 seems arbitrary, and their best explanation of why they choose this is it's what gets them a 14 stop measurement from the Alexa, but Arri intentionally underrates its sensors and if you talk with their reps they'll tell you the Amira, Mini, etc. are 15+ stops. And the official number from Arri has always been 14+ anyway. That's why I see the comparisons as useful, but to me the actual measurement I'd derive from the S1H's result are the 13.8 they find at SNR=1 plus a bit more from them placing the first wedge below clipping. So about 14 stops. Likewise all their numbers seem low to me.

    Numbers like "usable dynamic range" and Cinema5D's decision to sort of arbitrarily decide a cut off point for noise have been discussed in the past and never that productively. Canon took issue with their results on the C300 Mk II and released their own tests that correlate more closely with 14-15 stops if read traditionally rather than by Cinema5D's arbitrary (however useful for comparison) metrics. If you're interested in useable dynamic range in the field I find Geoff Boyle's over/under tests on CML more helpful anyway as you can see an entire scene and where different channels clip and there are some cameras that clip certain colors sooner or less attractively. Of course the Alexa does best. 

    If the S1H results are heavily influenced by noise reduction I don't know. I didn't know the Ursa Mini had no NR at that, that's impressive if true. I haven't had issues with noise reduction on either camera, but I have read about the S1H having ghosting issues for other people so clearly others have. I'm not really concerned with that, though, as I'm not planning to buy either camera. I'm just trying to understand how you can get 14 stops of dynamic range from a 12 bit ADC.

    The ADC bit-depth numbers you see (12, 14 or even 16) are quantisation accuracy, they themselves do not act as ceilings or floors.

    It's the SNR measurement threshold that sets the floor, the last few stops are always buried in noise, and noise reduction is an extremely effective way to increase SNR, especially in video mode due to the temporal nature. That's how they got more than 12 stops of DR from 12bit ADC.

    Current ALEXA sensors use 14bit ADC, but because the ADCs are off-chip, they themselves introduce a bit more noise than modern on-chip ones, so the camera's 16bit ISP does a bit of noise reduction (and other ARRI magic). For this reason, 14 stops is a good benchmark, so I wouldn't look at SNR=1 results, but they publish all the numbers and I respect each individual's own interpretation.

     

     

     

  9. 42 minutes ago, thebrothersthre3 said:

    Yeah its more like 12 actual stops of dynamic range. Numbers just depend on your testing methods though. Its one of the reasons I got the URSA mini 4.6k. The 12.6 stops in RAW measured by Cinema 5D are actually genuine as there is no noise reduction going on in RAW. 

    BRAW is not really RAW in a conventional sense, it's partially debayered and processed. And there's absolutely noise reduction going on in BRAW, however BMD seem to have turned it down on 4.6K G2 vs G1 (12.1 stops in BRAW on G2 vs 12.6 on G1)

  10. 21 minutes ago, TheBoogieKnight said:

    Everything I've ever read on the S1 says the converter is 14-bit. This would make sense as it outputs 14-bit RAW images and even Sony's technical documents state 14-bit so why is it only 12 bit? Just readout speed for video so they had to do that?

     

    On an unrelated note, do people generally think an S1H is still worth buying with the R5 around the corner?

    In stills mode, they use 14bit ADC. In video mode it's 12bit, because to achieve video frame rate (at least 24fps), ADC bit-depth has to be dropped to increase speed.

  11. 1 minute ago, Andrew Reid said:

    RAW sensor data does not have a "format" other than being RAW sensor data. No LOG, no colour profile, no white balance.

    It's output as RAW data but the Ninja V I think interprets RAW as V-LOG on the screen, so that you can use a LUT.

    Well there are actually RAW formats, ARRI and Canon uses 12bit logarithmic RAW encoding.

    In this case, ProRes RAW is designed to be linear.

  12. 10 minutes ago, Andrew Reid said:

    Let's try and get a bit deeper into it... Not saying it isn't a bug, but we could do with knowing a few things... What lens was in use? What level of IBIS was turned on? Boost mode or just sensor shift? What focal length? Was it a manual focus adapted lens and was the focal length input into the menus? Or was it a native Fuji lens? If so, did it have OIS?

    All the info is here:

     

  13. 35 minutes ago, Andrew Reid said:

    https://www.raspberrypi.org/products/raspberry-pi-high-quality-camera/

    Specs here imply it does output RAW?

    • Sony IMX477R stacked, back-illuminated sensor, 12.3 megapixels, 7.9 mm sensor diagonal, 1.55 őľm √ó 1.55 őľm pixel size
    • Ouput: RAW12/10/8, COMP8¬†
    • Back focus: Adjustable (12.5 mm‚Äď22.4 mm)
    • Lens standards:¬†C-mount,¬†CS-mount (C-CS adapter included)
    • IR cut filter:¬†Integrated
    • Ribbon cable length: 200 mm
    • Tripod mount: 1/4‚ÄĚ-20

    Yes obviously, those RAW formats are standard in MIPI CSI-2 interface protocol.

  14. 1 hour ago, hoodlum said:

    An interesting comment from Sony on the 108mp sensors vs the latest 12mp sensor.

    https://***URL removed***/news/8550800535/sony-provides-an-in-depth-look-at-the-sony-xperia-1-ii-camera-tech

    "Sony says the conventional design of the sensor offers faster read-out speeds than the pixel-binning Quad-Bayer technology deployed in most current high-end phones. The entire sensor can be read out in 10ms versus 32ms for a 12MP image from a Quad-Bayer sensor."

    Again, marketing BS.

    Sony uses DBI stacked sensor with DRAM, Samsung's 108MP sensor is not stacked (but Samsung does have stacked sensors), of course it's slower.

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