Cano EOS 80D TV mode behaviour

Discussion in 'Canon EOS Digital SLRs' started by albert_shooter, Apr 21, 2023.

  1. albert_shooter

    albert_shooter New Member

    Joined:
    Apr 21, 2023
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    Canon EOS 80D
    Hello mates,
    I am starting to use TV mode on my Canon EOS 80D camera.
    When I use TV mode and the speed that I select is too high the camera automatically switches to a lower speed to get a "correctly exposed" image. Is there a way to avoid this behavior (I prefer that the camera keeps the speed that I have configured even though the image looks underexposed.
    Thanks in advance.
     

  2. johnsey

    johnsey Site Moderator Staff Member Site Supporter

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    What is your aperture? Maybe it cant open the aperture up any further and it had to slow the shutter down to get the needed light.
    I'm also not sure how they handle ISO auto in the TV and AV modes as i never use it. But if the ISO is not going up you could bump it manually. I could experiment here when i get a chance see whats up with those auto modes but i think i gave you some info to look at either way.
     
  3. albert_shooter

    albert_shooter New Member

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    Canon EOS 80D
    Hello,
    When I use the TV the camera opens the aperture to the maximum of the lens which is 2.8.If I use the ISO in auto mode or manually the results are the same .The camera changes the speed when there is now enough light.
    This doesn´t happen when I use AV mode (when there is no enough light the camera keeps the aperture that I set up)
    PS:Thanks in advance for your help.
    Regards.
     
  4. johnsey

    johnsey Site Moderator Staff Member Site Supporter

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    So
    Not sure I exactly got my question answered....

    So....
    In TV you set shutter, the aperture will auto set but can only go as far as wide open, to compensate it adjust shutter down further since it ran out of options with lens aperture being wide open already. I would expect in ISO auto it should have moved the iso up to its limit before forcing the shutter below you manual choice.

    In AV mode you set the f stop, it will choose shutter even if it is very slow, you have a lot more rang where you can go for a 15sec long shutter if needed.

    https://gdlp01.c-wss.com/gds/0/0300022720/01/EOS_80D_Instruction_Manual_EN.pdf
    On page 151 you have options for dialing in ISO range, and even a lock on how slow to allow the shutter before ISO auto kicks in.

    It is hard for me to speak to the exact settings and light situation you are in, but you have maybe 7 stops on the lens f stop and 20 stops of shutter speed so are far more limited on the f stop before it cant go any further and the camera finds light elsewhere.
     
  5. johnsey

    johnsey Site Moderator Staff Member Site Supporter

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    Is your intent to under expose the image?? Because by using an auto mode the camera will try and force what the meter perceives as a proper exposure be it by slowing down the shutter further or increasing ISO to be very noisy. It sounds like your lighting is pretty dark and your not going to be able to freeze action /motion blur without a flash.

    So if you really want a faster shutter speed and the lens is wide open and your ok with it being under exposed then you should be either dialing in those stops of under exposure into the exposure compensation, or shooting in manual mode when it lets you lock in both and create the image despite being under exposed.
     

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