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Otago

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  1. So the 4K raw is full frame and down sampled 6K ? I haven't seen anyone confirming that the RAW is full frame. Any word on the ISO 6, 25 etc ? Does that give you full dynamic range in video or does it just move middle grey for exposure ? If it really does ISO 6 with fulll dynamic range either side of middle grey then that would be huge for me, never need another ND filter ever again and I can shoot video with M lenses and almost put it in my pocket.
  2. Otago

    Lenses

    I don't understand how the photo site size can change the dof, unless it is massive and there are so few samples to judge sharpness from. I could sort of see how it could be true for film, a flat CCD or CMOS with micro lenses vs a multilayered sheet. I'm obviously out of my depth with the maths behind all of this, is there a book or paper that you know of to explain it all ?
  3. Otago

    Lenses

    Yes, it's pretty obvious when you state it like that 😀
  4. Otago

    Lenses

    I was trying to figure out why we were wrong, the optical system hasn’t changed so the depth of field hasn’t changed - this is pretty fundamental in optical systems I have worked on. The bit that we were missing, as Kye says with the circle of confusion, was that while the optical system hasn’t changed, the viewing conditions have. The depth of field ( effective to the viewer of the output ) is the same for any size sensor as long as the output is scaled similarly to the input I.e. FF35 is viewed twice the size of M43. The circle of confusion is related to both the input and output size and scaling that changes the visible depth of field. I think of it like zooming into 100% , I can see whether something is actually in focus but I couldn’t tell when scaled to fit the screen, the difference won’t be as apparent as that example though. This is interesting to me because it explains why FF35 looks so good on a phone but can be too shallow on a big screen, and may explain some of the rush to the bigger sensors - as the images we view get smaller we need shallower depth of field to match the depth of field we see ourselves or are accustomed to in media. What I haven’t quite wrapped my head around yet is whether it changes the absolute level of blurriness of the out of focus areas. My initial thought is that it doesn’t, it just changes the rate of transition between acceptable sharpness and out of focus but not the absolute blurriness ( I’m sure there’s better terms for this ) Anyone got any pointers on that ?
  5. Otago

    Lenses

    I think you are correct - it's the same lens, how could the depth of field change ? They may be taking into account circle of confusion and resolution of the cameras, do they say how they calculate the limits for near and far limits ? It could also be that they are working back from the 2x crop and that is a problem with their methodology or code. I could see this error coming in if they calculate the depth of field based on it being a 140mm equivalent and working back, but that is wrong.
  6. The problem with the DPAF in anything but the most recent EOS Cinema bodies is half the features don't seem to work with lenses which aren't STM ( all my lenses are USM ). The C200 and C300mkii both use all the autofocus features with the USM lenses but are still expensive in the case of the C300mkii or produce large data rates ( or low 8-bit ones in the H.264 codec ) in the case of the C200. The C500mkii is rumoured to be coming out soon and I'm hoping it's going to be very successful, so there will be some more C300mkii's and C200's hitting the used market for people like me to hoover up. To get sharp 1080p it has to be from an over sample, like the EOS Cinema line, line skipping and pixel binning drop you below the real 1080p resolution because the bayer pattern doesn't deliver a true 540 line pairs required for HD, even the 4k is only really 2.8k - you need 6k bayer for a true 4k resolution file. Only the Cinema Eos line does this over sampling in the Canon line up but plenty of other cameras like the Panasonic GH5 and S1 and S1H do it ( but don't have the DPAF )
  7. A 4k bayer sensor doesn't provide 1000 line pairs so what we are seeing in the pocket 6k is real 4K resolution ( i.e. 1000-ish line pairs). A 4K bayer sensor works out about 2.8K of actual resolution, I think that's why lots of people weren't blown away by moving to 4K vs HD from an over sampled sensor. Sticking with the Canon C lineup that means the real resolutions have been 1080p from the C300 ( 4k sensor over sampled to 1080p) C300 mk2 is 2.8K recorded in a 4K file and the rumoured C500 mk2 is going to be 4K from an over sampled 6K sensor. I think Canon are struggling to keep up with Sony, the one constant among all the new cameras we are all raving about is the Sony sensor in them ( I think ? Is anyone else making their own sensors apart from Canon ? ) It could be that they run very hot when sampling the full sensor and that's why they are only reading the full sensor in cameras that have fans and a decent thermal mass, or the processors and driving circuitry do.
  8. It also stops a future PL mount from rotating when using a follow focus, no point in having a locking pin in one mount if there isn't one in the other. Could be confirmation of a Varicam and EVA L mount is coming, it would make sense for them to standardise on that mount.
  9. Does the camera do the 3:2 pull down internally then or is there something happening to the clock signal itself ? Do you know if it's just the sensor and driving electronics for it that change frequency between 50Hz and 60Hz or does that whole camera get a frequency change ? Anyway, that's that theory debunked 😀
  10. I think that some cameras use different clocks for the 25/50p and 30p/60p, which is why you have to restart the camera when you change that setting. I don't know if these Canon cameras do though. It's possible that 24p would need another clock circuit, and leaving that out might save some space on the board and reduce the cost slightly. If that is the case, I could see there being an argument for there being a real ( but minor ) cost saving to leaving out 24p, but also happens to be a "total coincidence" that it forces some people to buy the more expensive camera 😉 I also suspect that there is a real technical reason for no over sampled 4k from full frame, Canon do seem to be struggling to keep up with Sony on sensor technology and perhaps their sensors get too hot or read out too slowly to do it, or their processors aren't fast enough. I think the CEO would rather people thought they were segmenting products rather than being really far behind with technology, that would look bad to their share holders.
  11. It is very dependent on your local tax laws, in the UK for instance, you can get into trouble claiming a percentage of mortgage payments based on square footage when it comes time to sell. My chats with accounts have always saved me more than they have cost, but I file myself and only go to them when everything is properly formatted for advice.
  12. I think I am probably not using the right terminology, or haven't understood what noise or sharpening artefacts look like. Probably both 😀 The image look smoother to me on the BMPCC 4k ( when not at 100% ) for some reason. I agree that the BMPCC 4K is definitely noisier, is it just there is more detail coming from a 6k sensor downsampled to 4k in the S1 rather than a 4k bayer sensor on the BMPCC 4k ? I have played around in Resolve with the files but I am still far from proficient 😀 As I said, I think they both look great, it's very much nit picking for the uses I have for the camera - oh to have a few weeks and a far higher credit limit to try them all out.
  13. Sorry, should've been clearer, I meant the noise reduction and sharpening. I'm wondering if it can match the smooth look of Pocket 4k, it looks amazing but the Pocket 4k looks nicer to my eyes, even with the slightly lower dynamic range - perhaps it's RAW vs H.265 though.
  14. Does it go lower than that ? If you're bored it would be nice to see what a range of setting do to the image - but only if it would be useful to you obviously!
  15. The logistics of selling digital products through distributors and then retailers is by no means a solved problem - everyone wants their cut and is afraid of setting a precedent. The distributors know their business is dieing, there are so few camera shops now that the manufacturers could take on selling directly to retailers quite easily but the distributors are fighting tooth and nail to keep their businesses alive. Like a fungal nail infection that just won't go away 😉 What were the settings on the S1 for this ? The S1 looks too sharp, to me, in comparison to the BMPCC 4K but they both look really, really good! Dancing on the head of a pin.
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