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  1. Member
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    Hi!

    Does video grain occuors usually even in broad daylight? Is it normal?

    I tried to record video even with lossless Ut video via Camlink 4K HDMI to USB3 adapter, but the grain is the same even in broad daylight.
    I used Sony Ax700 and Ax53 camcorders

    The result is always grainy.

    Watch the photo:

    https://i.ibb.co/j4GKWCH/C0020-MP4-20201120-104044-838.png

    Watch the pattern on the blue Sky.
    Last edited by Video Grain; 21st Nov 2020 at 11:32.
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  2. Video Restorer lordsmurf's Avatar
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    Grain is also determined by the camera glass, shutter and ISO.
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    Originally Posted by lordsmurf View Post
    Grain is also determined by the camera glass, shutter and ISO.
    Do you think, if I use high shutter speed, (despite the sensor get enough light), the patterns will appear in flat surfaces?


    Watch this short video, especially the blue sky and flat homogenous surfaces produces that: https://sendgb.com/S7HfZKzm1TA
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  4. Turn down the gain. Most decent camcorders will go to at least -3. (FWIW I don't find the small amount of noise distracting at all, indeed it makes the image look filmic.)
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    Originally Posted by smrpix View Post
    Turn down the gain. Most decent camcorders will go to at least -3. (FWIW I don't find the small amount of noise distracting at all, indeed it makes the image look filmic.)
    I have only 0 DB option, and I alwas shot videos with 0 DB in gain control.
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  6. Video Restorer lordsmurf's Avatar
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    High shutter will probably just increase grain.
    Same for low aperture.
    And higher shutter causes lower aperture, which is based on glass.
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    Originally Posted by lordsmurf View Post
    High shutter will probably just increase grain.
    Same for low aperture.
    And higher shutter causes lower aperture, which is based on glass.

    Yes it is true, this phenomenon is less signifficant is longer slower shutter speeds even on tripod. This is true all of my former camcorders too. But what is the cause of this phenomenon, practically in all of my cameras (let it be Sony Canon JVC, or Panasonic), and it exists even with lossless HDMI recording too.

    Did you try this with your camrea in 8bit 4:2:0 recording? Flat surfaces and Sky became a bit grainy in faster shutter speed, even in blinding strong bright sunshine too...
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  8. Originally Posted by Video Grain View Post
    Originally Posted by lordsmurf View Post
    High shutter will probably just increase grain.
    Same for low aperture.
    And higher shutter causes lower aperture, which is based on glass.

    Yes it is true, this phenomenon is less signifficant is longer slower shutter speeds even on tripod. This is true all of my former camcorders too. But what is the cause of this phenomenon, practically in all of my cameras (let it be Sony Canon JVC, or Panasonic), and it exists even with lossless HDMI recording too.

    Did you try this with your camrea in 8bit 4:2:0 recording? Flat surfaces and Sky became a bit grainy in faster shutter speed, even in blinding strong bright sunshine too...
    Shutter speed, exposure (aperture) and gain all control how much light hits the sensor. Faster shutter and smaller aperture means less light hits the sensor. The camera compensates by increasing gain to get a proper exposure. Increased gain means increased noise. This is Photography 101. (And video does not have grain -- large particles of silver -- it has electronic noise.)
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    Originally Posted by smrpix View Post
    Originally Posted by Video Grain View Post
    Originally Posted by lordsmurf View Post
    High shutter will probably just increase grain.
    Same for low aperture.
    And higher shutter causes lower aperture, which is based on glass.

    Yes it is true, this phenomenon is less signifficant is longer slower shutter speeds even on tripod. This is true all of my former camcorders too. But what is the cause of this phenomenon, practically in all of my cameras (let it be Sony Canon JVC, or Panasonic), and it exists even with lossless HDMI recording too.

    Did you try this with your camrea in 8bit 4:2:0 recording? Flat surfaces and Sky became a bit grainy in faster shutter speed, even in blinding strong bright sunshine too...
    Shutter speed, exposure (aperture) and gain all control how much light hits the sensor. Faster shutter and smaller aperture means less light hits the sensor. The camera compensates by increasing gain to get a proper exposure. Increased gain means increased noise. This is Photography 101. (And video does not have grain -- large particles of silver -- it has electronic noise.)
    Hi!

    Gain level was zero 0 db, and it always happen in blinding bright sunshine on the skyand flat simple surfaces. All Camcorders what I ever had produced that with zero db gain in bright sunlight over around 1/100 shutterspeed.

    Here is an other sample file about it: you can download it from here: https://transferxl.com/08gRrbT1ZCxmt
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  10. All image sensors produce noise.

    https://en.wikipedia.org/wiki/Image_noise

    Pay particular attention in this article to gaussian noise and the sensor effects.

    If it's any comfort, it appears you are doing the best you can with the gear you have. Focus on the things you can control. Any distracting noise you have is more than overwhelmed by your distracting shaky camera handling.
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    Originally Posted by smrpix View Post
    All image sensors produce noise.

    https://en.wikipedia.org/wiki/Image_noise

    Pay particular attention in this article to gaussian noise and the sensor effects.

    If it's any comfort, it appears you are doing the best you can with the gear you have. Focus on the things you can control. Any distracting noise you have is more than overwhelmed by your distracting shaky camera handling.
    Also human eyes. I can see similar phenomenon when I watch the blue sky during sunny weather. I see small vibrating noise points on the sky. Similar to gaussian noise.
    Last edited by Video Grain; 22nd Nov 2020 at 04:35.
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  12. Member dellsam34's Avatar
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    Every imaging sensor has a pixel structure even our eyes, The good thing about our eyes is we don't have a digital zoom, what you see is what you get, but zooming video files or pictures you will eventually see the elements that make up the picture. So do what our eyes do, don't digital zoom it, just watch the whole frame.
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  13. Originally Posted by dellsam34 View Post
    Every imaging sensor has a pixel structure even our eyes, The good thing about our eyes is we don't have a digital zoom, what you see is what you get, but zooming video files or pictures you will eventually see the elements that make up the picture. So do what our eyes do, don't digital zoom it, just watch the whole frame.
    Hi!

    I have never used digital zoom in my life.
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  14. Member dellsam34's Avatar
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    No one does, except cyborgs !!!!
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  15. Member Cornucopia's Avatar
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    I.USE.
    DIGITAL.
    ZOOM.
    4-EVER.


    *************

    But seriously, am guessing the OP needs to get used to discerning between noise, grain, compression artifacts, and the posterization effects of 8bit vs 10 or 12bit imaging.

    Scott
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  16. Originally Posted by Cornucopia View Post
    I.USE.
    DIGITAL.
    ZOOM.
    4-EVER.


    *************

    But seriously, am guessing the OP needs to get used to discerning between noise, grain, compression artifacts, and the posterization effects of 8bit vs 10 or 12bit imaging.

    Scott
    Yes, you have right in the case of flatsurfaces, but what about the Sky? Even my eyes see the blue summer sky with patterns. I asked other people, they have the same experience, despite human eyes did not suffer from low (8 bit) colors. ))
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  17. Since noise is caused by the sensor, if the OP wants to reduce noise, he should get a camera noted for low noise. My son-in-law is a professional photographer, and he shoots with high-end Canon DSLRs. He has shown me low-light pictures, with the ISO boosted up into the mid-thousands, and the grain is barely perceptible.

    So, that's what I'd shoot if the objective was to get the lowest grain possible.

    It will, however, cost you some serious money.

    [edit]Here is an example. As you can see, it was shot in extremely low light, in Iceland, after midnight. Click on the image to zoom in.

    SOG Knives
    Last edited by johnmeyer; 3rd Dec 2020 at 10:44.
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  18. Member Cornucopia's Avatar
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    @johnmeyer, Nice & Smooth. Good example.

    @VideoGrain, I suspect that in viewing the real sky you are seeing shadows of microbes in your vitreous humor, or ghost vessels on your retina. Perhaps you should get your eyes examined. You shouldn't be seeing "grain" in something that is uniform beyond the resolving power of your sensor (in this case your eyes). This may sound mean or bold, but I don't mean it to. Seriously, you should not be experiencing that in real life.

    Scott
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  19. Originally Posted by Cornucopia View Post
    @johnmeyer, Nice & Smooth. Good example.

    @VideoGrain, I suspect that in viewing the real sky you are seeing shadows of microbes in your vitreous humor, or ghost vessels on your retina. Perhaps you should get your eyes examined. You shouldn't be seeing "grain" in something that is uniform beyond the resolving power of your sensor (in this case your eyes). This may sound mean or bold, but I don't mean it to. Seriously, you should not be experiencing that in real life.

    Scott
    Eye flora/eye micro biome and microbes are necessary for healthy eyes.

    https://theconversation.com/bacteria-live-on-our-eyeballs-and-understanding-their-role...cgEi3zitk5TSBE
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  20. Member Cornucopia's Avatar
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    And yet, it should not be driving one to distraction.


    Scott
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