• Roger Clark

      by Published on 08-06-2012 07:27 AM

      This post is derived from my web article: http://www.clarkvision.com/articles/iso

      What is ISO on a digital camera?

      Reading manufacturer literature, review sites, and online discussions, one is led to believe that ISO changes sensitivity, and changes exposure. These ideas are both incorrect.

      Myth #1: ISO changes sensitivity. False! Digital cameras have only one sensitivity, given by the quantum efficiency of the sensor, and the transmission of the optics and filters over the sensor. ISO is simply a post-sensor gain applied to the signal from the sensor.

      Myth #2: ISO changes exposure. False! When you change ISO on a digital camera, two things are changed ...
    • Most Recent Threads

      Bill Dix

      Synchronicity

      Thread Starter: Bill Dix

      Mallard Pair, from South Cape May Meadows last week. I do wish for the near wing to be a bit more raised; but I like the juxtaposition of the two heads

      Last Post By: gail bisson Today, 02:52 PM Go to last post
      Jonathan Ashton

      Goldfinch (Carduelis carduelis)

      Thread Starter: Jonathan Ashton

      Hand held, I have a couple of small sumacs in the garden and I thought this one might make for a colourful autumnal perch so I placed a feeder nearby

      Last Post By: Bill Dix Today, 02:47 PM Go to last post
      Stu Bowie

      NOVEMBER THEME - HIGH KEY

      Thread Starter: Stu Bowie

      I am trying to get members out of their comfort zone with new themes to test their skills. November's theme will be high key, and we all know that a subject

      Last Post By: Stu Bowie Today, 01:17 PM Go to last post
      dankearl

      Shooting in the Rain

      Thread Starter: dankearl

      A lot wrong with this photo, not quite sharp, not perfect exposure with very high ISO,
      but this is the best pose I ever get with the Greenies and

      Last Post By: Bill Dix Today, 02:51 PM Go to last post
      Steve Kaluski

      Watchful

      Thread Starter: Steve Kaluski

      Perhaps a 'marmite' shot, or not... but this was shot deep in the bush, light was ridiculous with little, or no opportunity until this female Leopard

      Last Post By: Gabriela Plesea Today, 03:35 PM Go to last post
      John Mack

      Milkweed seed

      Thread Starter: John Mack

      This image was created in Ithaca, New York on 9/15/19 at 7:47AM. Image processed in Lightroom and Photoshop.

      Camera on sticks triggered with

      Last Post By: Jonathan Ashton Today, 01:51 PM Go to last post
      Jonathan Ashton

      Red deer (Cervus elaphus)

      Thread Starter: Jonathan Ashton

      Hand held

      Image input equipment model : E-M1X
      Lens focal length : 300 mm
      Focal length in 35 mm film : 601.0mm
      Exposure

      Last Post By: Gabriela Plesea Today, 04:04 PM Go to last post
      John Mack

      Blue Jay

      Thread Starter: John Mack

      This image was created in Ithaca, New York on 2/9/18 at 10:21AM. Image processed in Lightroom and Photoshop.

      Hand held, 4x5 crop.

      Last Post By: Bill Dix Today, 02:43 PM Go to last post
      John Mack

      Bull Elk

      Thread Starter: John Mack

      This image was created in Benezette, Pennsylvania on 9/27/19 at 9:01AM. image processed in Lightroom and photoshop.

      Hand held, Small crop.

      Last Post By: Gabriela Plesea Today, 03:40 PM Go to last post
      Joseph Przybyla

      Tricolored Heron

      Thread Starter: Joseph Przybyla

      I captured this image at Circle B Bar Reserve in Polk County, Florida. Comments and critique welcomed and appreciated. Thank you for viewing.

      Last Post By: gail bisson Today, 01:43 PM Go to last post
      gail bisson

      Snowy Owl

      Thread Starter: gail bisson

      Things are absolutely dead here in Cape Breton- all the birds have migrated through and I am now just waiting for the winter birds to arrive.
      I

      Last Post By: dankearl Today, 10:53 AM Go to last post
      Giovanni Frescura

      lion

      Thread Starter: Giovanni Frescura

      Canon 1dx mark II
      Cann 70/200 is "
      1/80
      iso 1000
      f.3,2
      Made with light in background

      Last Post By: Stuart Philpott Today, 12:25 PM Go to last post
      arash_hazeghi

      Another harrier frame

      Thread Starter: arash_hazeghi

      here is another frame from the same adolescent female harrier I posted a few days ago. She was quite active at the sunset and gave me a few passes

      Last Post By: dankearl Today, 10:55 AM Go to last post
      Mitch Carucci

      NEITH 1907

      Thread Starter: Mitch Carucci

      Classic 1907. Photographed in the 1980s with new sky added.

      Last Post By: Mitch Carucci Yesterday, 03:45 PM Go to last post
      Sanjeev Aurangabadkar

      The Sprinter

      Thread Starter: Sanjeev Aurangabadkar

      A Wildebeest sprints and looks petrified of something (could be us) but the expression on the face was worth capturing and that too mid air. Light

      Last Post By: John Mack Today, 10:09 AM Go to last post
    Web Analytics