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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 12:32.
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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 05:35.
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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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