Black line in long exposure picture

Discussion in 'Technical Troubleshooting' started by Jwyn644, Aug 1, 2020.

  1. Jwyn644

    Jwyn644 New Member

    Joined:
    Jul 25, 2020
    Messages:
    7
    Hi! I was taking a long exposure picture of water flowing and I noticed a black line in the picture. I checked the lens and there was no dirt or hair on the lens and then in the other picture taken at a different angle theres no line. Any one got any ideas? Thankyou
     

  2. GDN

    GDN Well-Known Member

    Joined:
    Jul 22, 2018
    Messages:
    923
    Location:
    South Island, NZ
    Equipment:
    A little Canon stuff

    Any chance of posting an image with this black line?

    Is this line visible when you review the image to the cameras rear LCD, or is it only when you review it on your PC?

    Gary
     
  3. Caladina

    Caladina Active Member

    Joined:
    Jan 30, 2020
    Messages:
    230
    can you post the picture for us to see, also have tried taking a similar timed exposure of a white surface see if you can repeat the result?
     
  4. Jwyn644

    Jwyn644 New Member

    Joined:
    Jul 25, 2020
    Messages:
    7
    Hi! Sorry I thought I had uploaded it
     

    Attached Files:

  5. Caladina

    Caladina Active Member

    Joined:
    Jan 30, 2020
    Messages:
    230
    oh wow you got a pic of the invisible water serpent!!!! nice one.
    ok i not sure what it is but it does look like a hair or something, i have had a random hair or whisp of something blow onto the lens or lens cap then blow away again during a session then i only ever see it on one or two pics when i download them.
    fortunately it was just in two frames then gone the rest for me.
    if it was a straight line or something that kept cropping up in the same place regularly then you might need a second look.
    Nice picture btw :)
     
  6. Jwyn644

    Jwyn644 New Member

    Joined:
    Jul 25, 2020
    Messages:
    7
    Thanks! I did get the same line using a different lens in the same picture but since posting this I cleaned under 5he mirror with a cotton hud and i think it may have been a bit mucky
     
  7. johnsey

    johnsey Site Moderator Staff Member Site Supporter

    Joined:
    Apr 21, 2017
    Messages:
    801
    Location:
    Fargo, ND
    Equipment:
    5dMk4, 5dMk2, 20D, 70-200 2.8L IS, 100mm 2.8 Macro USM, 50mm 1.4, 85mm 1.8, 17-40mm 4.0L, Rokinon 14mm 2.8; Pixma Pro-100
    That is dirt on the sensor. Dust and fine hairs show up like this when then make it to the sensor and land on it. I would get long ones like that on my 20d all the time. You will only really see them when you shoot apertures upwards of 16. You want a good test shoot a blue sky stopped all the way down and you can see how dirty it is. You can search cleaning methods but do not use a qtip, you will introduce more fine threads in. Either factory dust sealed pads and a special solution or air blowers are the common approaches. Both you need to be steady and careful to clean.
     

Share This Page