Noise Reduction (long exposures)

Discussion in 'Olympus Cameras' started by Art, Dec 7, 2011.

  1. Art

    Art Mu-43 All-Pro

    Mar 13, 2011
    San Francisco, CA
    Just as I was getting into some long exposure time-lapse photography for both daytime (w/ND filter) and nighttime, I ran into this:

    Noise Reduct. option is unavailable if your drive mode is set to Sequential

    From E-PL2 and E-PM1 Manuals.
  2. Ned

    Ned Mu-43 Legend

    Jul 18, 2010
    Alberta, Canada
    Long exposure in burst mode? :confused:
  3. Livnius

    Livnius Super Moderator

    Jul 7, 2011
    Melbourne. Australia
    Not to hijack this thread but I have a long exposure/noise related question.

    When having completed the exposure for whatever the period you have set it to, the camera (my gf1 anyway) counts down an equal amount of a 50sec long exposure results in a 50 second countdown after the exposure complete with the dodgy looking spinning hour glass icon on the screen. Now I assumed initially that time was being used to write the data to the card....but I think I once read somewhere that during that 'write time' the camera is still analyzing the scene and using this new information and referencing it against the exposure to in effect assist correct the image by removing/reducing noise and other anomalies and as such, the camera should be left perfectly motionless on the tripod during this period.

    Is this correct ?
  4. Kind of. I think the camera is essentially taking a blank image (the sensor is recording but the shutter remains closed) for an equal exposure time, reading the noise from that image, and then applies a noise reduction to the first image based on those results.
    • Like Like x 1
  5. Art

    Art Mu-43 All-Pro

    Mar 13, 2011
    San Francisco, CA
    Not burst. To do time-lapse with Olympus I use built-in intervalometer function (aka anti-schock). E.g. 30s intervals between each 30s exposures. The camera is in sequential mode so it doesn't stop until battery runs out. Noise reduction menu is greyed out whenever sequential mode is selected...
  6. Livnius

    Livnius Super Moderator

    Jul 7, 2011
    Melbourne. Australia
    Cheers Nic.

    To your understanding, does the camera need to remain motionless during this period ?
  7. zerotiu

    zerotiu Mu-43 Veteran

    Sep 13, 2011
    ya, it's true. After I turn off the noise reduction feature, the process is done immediately. Thanks! I've searched the answer for this problem and I realized that my noise reduction feature is in auto mode. It's auto on when it's in lowlight situation.
  8. keith1200rs

    keith1200rs Mu-43 Regular

    Nov 8, 2011
    North Yorkshire
    No. The shutter is closed. The camera simply subtracts the shutter closed image from the image taken.

    • Like Like x 1
  9. hkpzee

    hkpzee Mu-43 All-Pro

    Sep 5, 2011
    Hong Kong
    Thanks for the clarification! This explains the queries I always had, when I took long exposure shots with noise reduction on. :thumbup: