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Robert Collins

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Everything posted by Robert Collins

  1. Well presumably there are 2 different tests. Relative dynamic ranges at 'base iso' and relative DR at higher isos (or low light). They are not the same - for instance Canon sensors have much lower DR than Sony sensors at base iso but they are pretty similar at higher isos. The 'Op' seems more interested in relative DR at base iso.
  2. Yes, I think that is self evident. Take a shot jpeg (8 bit) and raw (14 bit) and you can recover 1 to 2 more stops in raw. Also bit rate will effect DR - I can recover more highlights in a jpeg still than in the more heavily compressed video. These factors would certainly help both the GH5 and X-H1 get closer to A7iii DR in video relative to stills than the sensor size difference might imply.
  3. Interesting he says that the video is slightly better on the A7iii than the A7riii. I guess he means the FF 4k video.
  4. Shouldnt this thread be closed?
  5. An electronic variable ND filter would be a great feature but I read somewhere that Sony engineers said there wasnt enough room for one in an A7 body.
  6. I think we are on the same page here. I really wish Sony would be more transparent about their plans for the A7siii. I am in the market for another A7xiii body but want to wait to see if I should get the A7siii. I suspect others are in a similar position. Obviously telling people your plans can harm existing sales but I doubt anyone is really buying a new A7sii at this stage.
  7. In his latest tweets 'ositalv' says that in the 3rd beta version of the Mavic 2 prototype, DJI reduced the size of the sensor from 1' to 1/1.7'. Apparently it is probably the Sony imx226 sensor which at least does 4k 60. But disappointing. May have to wait for the Phantom 5.
  8. I am not sure that is the right way of looking at it. Sony is dealing with a sensor 4x the size of M43. That brings advantages in terms, of noise, DR and Dof. At the same time it likely means that they cant match M43/GH5 in the same form factor in terms of fps, bit depth and bit output for video.
  9. Honestly, all I really know is these conversations get horribly complicated, incredibly quickly. High isos provide benefits in low light by reducing read noise especially in low bit and dual isos can provide benefits in terms of cleaner images at high isos. When it gets to the stage of adding 6 stop NDs to reduce light on a sensor, so you can shoot at high isos (like 3200) when an iso is effectively an electronic gain of existing light (which is bound to increase noise), it all begins to sound like nonsense!! I also think it is unnecessary (for say my camera to say it is at iso800 when it is at iso100 internally). We are not supposed to be electrical engineers...
  10. Actually this is a bit misleading. For instance, with the Sony A7r3 if you shoot sLog2 your minimum iso is iso800 and this should give you max DR. But if you examine the data (see Iliah Borg, Rawdigger) you will find that the A7r3 'actually' shoots the footage at iso100 (rather than iso800). Which explains why you have to shoot 8bit video in sLog - 2 stops overexposed!!
  11. True. However, I also think the opposite is true. Sony came out with the A7iii at a very aggressive price point because they were well aware that Canon and Nikon were likely to enter the high end mirrorless market within the next 12 months.
  12. That has been my experience when comparing my Batis 85 to my GM 85 on the A7riii for video.
  13. Havent Sony had dual iso for years - at least back to the A7RII. Certainly seems like it from the numbers....
  14. True. But if you increase the 'form factor', keep the ibis, throw in a variable electronic nd filter and a flippy screen, all you end up with is an FS5 mkii rather than an A7siii....
  15. https://www.dxomark.com/Cameras/Compare/Side-by-side/Sony-A7-III-versus-Sony-A7R-III-versus-Sony-a9___1236_1187_1162 BTW the DXOmark numbers have been released on the A7iii. There are no surprises but they are impressive - they are well within spitting distance of the A7riii and the D850. The question is where does this leave an A7siii? I know absolutely nothing but I am pretty skeptical we are going to see one soon... 1) Just looking at the numbers there seems no real justification for a 12mp sensor for US$3,000 - the delta on the lowlight performance I think would simply be too low to make it worthwhile simply because the A7iii at US$2,000 is so good.... 2) Of course, there is still room for internal 10 bit recording and/or say 4k/60 but I am not convinced given all the overheating problems that Sony (and actually pretty much everyone else has had) in recent years, that Sony can provide that with a FF sensor.... 3) There is perhaps the potential to take the A9 sensor and its insanely good sensor readout of data to make a video cam with next to no rolling shutter but as we didnt see that with the A9, I kinda doubt it....
  16. Seems to me that a bit of 'camera bashing' is a necessary evil in every camera thread. And it seems that the X-H1 has come through 63 pages of BS pretty much unscathed, so that Fuji is really onto something here, and that this camera is really growing on people.
  17. Well apart from his ASAP is April 1st?
  18. Its pretty well known that Fuji does a 2/3 stop fudge of its iso to make it look better as illustrated by his exposures. I am a little skeptical though of his claim of a 2 stop difference based on essentially 'Sony' sensors with a one stop difference.
  19. The human eye can see at least 20 stops of dynamic range which is why we can easily say view a sunset without the sun blowing out and see more detail in the shadows than a camera can produce. There are different ways of measuring dynamic range - it is not an exact science. So for instance, Sony can claim 15 stops of DR for its A73 and that might well be right by the way they measure it. DXOmark will almost certainly score it at around 14 stops using their method. By Bill Claff's measurements it is 11.6 stops (slightly below the A7R3 at 11.76) http://www.photonstophotos.net/Charts/PDR.htm The Red cameras do score 'extraordinary' high DR results. https://www.dxomark.com/red-helium-8k-dxomark-sensor-score-108-a-new-all-time-high-score2/ They claim 16.5+ stops of DR but DXOmark measures it 15.2 stops (similar to say Sony claiming 15 stops and DXO measuring at 14). What makes this 'extraordinary' is that the RED cameras are not even FF but are outperforming the best FF cameras (which makes no sense.) Clearly Red hasnt magically improved QE of sensors relative to say Sony. DXOmark says they are using 'temporal noise reduction' which is a fancy way of saying they are combining multiple images and processing them for better image quality. As an example you could take your camera and do bracketing -2,0,+2 and combine them in post which would increase the amount of dynamic range you could capture. What Red is effectively doing is equivalent to this but doing the post processing in camera.
  20. I am interested in this perhaps you could post a video and show us what you mean. One thing I have noticed with the 'A7riii' is that video is quite a bit smoother when you use a lens with OIS than one without. It is evident here courtesy of 2 videos from 'Cameralabs' First video is with the 85 1.4 GM (no OIS) Second, is with the 24-105 f4 (with OIS) Yes, I know what you are thinking. One is a wide angle, one is telephoto. But I have tried video with both the 85 1.4 (no OIS) and Batis 85 1.8 (with OIS) and the Batis is noticeably better. I also dont think this a 'problem' of the ibis but more a 'feature'. I think the 'ibis' with the non ois lens is trying to keep the image 'steady' or 'fixed' which would be perfect for stills but makes it jerky for video. At some point manufacturers will need different ibis for stills and video (doesnt the Fuji X-H1 already have this?) The way Sony cameras are designed they automatically fix/fudge this issue over time. Once a month the camera does pixel remapping which interpolates dead pixels (ever notice a 'thud' from an A7 camera a second or so after you switch it off?) That is why the date fix works - moving forward the date by at least a month tells the camera it is time for pixel remapping. BTW, every CMOS sensor has dead or hot pixels - so anyone claiming that my x camera never had a dead pixel is simply stating that they havent seen one rather than they exist and have been remapped. I thought that Sony QC limited dead pixels to 1:10,000 or .01%. Doesnt sound too bad but it does equate to 2,400 pixels on a 24mp camera. So I find it difficult to get excited about 40 dead pixels.
  21. Well inherently pixel interpolation is a 'fudge' more than a 'fix' but camera companies are pretty good at it..... I would also imagine that if there were a significant number of bad pixels, you could have the camera/sensor replaced under warranty.
  22. Yes, the same with the Olympus EM1 I had - there was a 'menu item' for 'pixel remapping'. Sony obviously thought they already had enough menu items, so they would make it even more complicated....
  23. Actually this is a pretty old fix for dead/faulty pixels on a Sony sensor. Basically any sensor will have a number of bad/dead pixels. I believe that QC limits the number to 1:10,000 (or something like that.) What the camera does when it sees a dead pixel is interpolate it. What happens if you set the date well ahead of the actual date is that the camera searches for dead pixels and then remaps the sensor for any new dead pixels by interpolating any dead pixels it finds.
  24. I dont really get the 'smart marketing' from Canon. It more strikes me as a company that is dependent on 'brand loyalty' for sales not realizing that brand loyalty is a two way street. From a marketing perspective Canon just seems to be a company with a 'lot of potential' that 'simply isnt making an effort'. That maybe not true but it is the impression Canon gives. At the opposite end of the scale, Sony's marketing 'perspective' seems to be around 'trying ' to give as much 'value' for as 'low a price' as possible.
  25. I still struggle with the concept of large (and quite expensive) cameras with small sensors then offering fairly expensive adapters (speedboosters) to emulate FF. Why not simply buy a FF camera in the first place. If a smaller sensor camera doesnt offer an advantage in terms of 'size' (actually being smaller) or 'price' what exactly is the point? Admittedly it does make some sense for Panasonic in video as they offer 10bit, high bit rates and 4k 60p which the FF companies havent really shown is possible in FF but I do think it is only a matter of time. The industry, I think, is trending to FF.
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