ISO Sensitivity

As photography means painting with the light, any photographer is in control of its composition (elements arrangement in the frame and even adding photo effects later or cropping it for a better result, for example) and exposure – when you press the shutter release you are just telling the camera to stay open for a certain amount of time and let a determined quantity of light in, reaching the camera sensor (digital) or film.

The exposure is controlled by 3 (three) adjustments we make in the camera: shutter speed, aperture and sensitivity. Shutter speed and aperture ultimately control how much light comes into the camera (we can compare this to a water tap – how much you open the valve and for how long will dictate the amount of water that will flow)… and how much light is needed for a certain exposure is determined by the sensitivity of the medium used (today it has been expressed as ISO numbers – and as ASA not so long ago).

In the digital cameras world today, we can find ISO ranges from as low as 50 up to 204,800, being the normal range placed somewhere between 200 and 1600. These numbers have some qualities associated with them: it sets the amount of light needed for a good exposure, and the lower the number, the more light is required, and as a consequence for a fixed aperture, a slow shutter speed will have to be used; and will influence the amount of noise in the image.

So, if you have lots of light (or have the camera mounted on a tripod), the lower the numbers you can set, and on the other hand, when you do not have lots of it or you need a faster shutter speed (for action and sports shots, for example), you will need to raise the ISO (and this is what the AUTOISO settings in your camera do: adjusts the ISO settings so you end up with the correct camera measured exposure for a given situation. You normally set the minimum and maximum range you want the camera to automatically adjust the ISO based on your acceptable quality and speed requirements).

It is worth knowing that each time you double the ISO (for example, from 100 to 200 or from 400 to 800), half of the light is needed for the same exposure, and vice-versa.

As we mentioned above, noise levels will also be influenced by the ISO settings, and the higher the number is, the more noise and visible grain an image will have. We normallywant the images to have the least amount of noise as possible.

Today, most digital cameras can make good quality images at ISOs up to 800 or 1600 and above, but several aspects affect this, from the sensor type a camera uses (for example, the size of the pixels used on the camera’s sensor, which are larger in SLRs compared to the compact ones. Larger pixels result in less noise and SLRs have larger sensors with larger pixels) to the amount and type of noise reduction algorithms and systems used in the cameras.

Introduction to ISO in Digital Photography

The technology of camera has been developed rapidly. The latest camera invention is DSLR camera. DSLR is a digital camera which could create the digital picture. Digital camera is the technology which is able to stabilize the image. So, the pictures that are produced by a digital camera are cleaner than the traditional one.

The sophistication of the camera digital should be balanced with the owner skill. It will be useless if you have a digital camera but do not know well how to operate it. Therefore, you have to learn about the main component of digital camera and photography such as ISO.

ISO is the crucial thing on the digital photography. It can determine how the photo that you take is good enough in getting balanced light. ISO in digital photography measures the sensitivity of the image sensor. The principle of ISO is not much different with the ISO in film photography. When you set the ISO in a low number, so it will be less sensitive to the light and fine the grain.

In general, the digital camera provides the feature which is given to user to have authority in setting their ISO, even though you can move to the “automatic” mode. This is very beneficial since the camera can adjust the ISO automatically, depend on the situation. It would be wise, as the beginner, you know about ISO and set ISO in a different situation.

  • Get Over It. If you set ISO in high setting (800), it is the perfect ISO to help you freeze the action at several events. If you love to shoot the moving action such as sport, the high ISO is good for you. 1/1000s is a common for freeze action. If you set ISO 3200, you would get some noise in the right amount. You may see the sharp noisy image for the better picture than blurry fine grained one.
  • Lighten Up. The common problem of ISO setting is the noise; the best way to minimize the noise is making sure that the subject is exposed brightly. You can expose your image little bit brighter than usual. It will create the better of your image.
  • Auto ISO. You can set your camera to AUTO ISO. It can be more value instead of you set manually. The ISO setting depends on the scene you choose. When you set the ISO manually, the exposure will adjust ISO to make the image look brighter or darker, it is so pretty handy.
  • Shoot RAW. The other tip to reduce the noise after you take a picture is using Photoshop application. Apart from that, the lightroom4 is more useful than Photoshop or Adobe camera RAW for the similar adjustment. Actually, on RAW, it is very nice to reduce the noise in jpg files.
  • Black and White. Mostly, black and white effect is used to create timeless accent. So, the noise will look like grain. So, when your image has so much noises, the solution is using black and white effect and look like historic style.