Tag Archives: grain

Grain

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Not the kind you eat.. the kind you look at. Grain. Or noise, as it is called in digital pictures. Bad! Grain must be avoided at all cost!

Perhaps not.

  • First: there is a difference between the look of electronic “noise”, which results from the use of small sensors, high ISO values, or great exposure pushing in post-production, and film-type grain. This electronic kind of noise is ugly.
  • Second: while electronic noise is ugly and must be avoided, not so for film grain; not necessarily. Film grain can be very attractive, as in 1960s photos shot on Kodak Tri-X film.

Which is why you can now add film grain in many apps. Like in Lightroom.

Here’s a detail of a picture. You need to click to see it at original size. This screen print shows the EFFECTS pane in the DEVELOP module:

Now the same, with some grain added (look at the slider on the bottom right):

Again, click all the way through to the “Full Size” link. You will see a difference somewhat like this:

I often add some grain to my black and white images, to give it that authentic film look. As an added bonus, this treatment also hides imperfections that can result from sharpening.

Don’t go crazy and add 100% grain to all your pictures – but used judiciously, this is a great addition to your arsenal of tools (if I can be forgiven for mixing metaphors).

 

ISO to the rescue

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A beginners tip, today. About ISO.

All being engineers, you all know that ISO stands for the International Standards Organisation, of course. And you all know that the engineers in Japan chose this term to indicate the camera’s sensitivity setting. You can set the sensitivity of your camera, where more sensitivity means you can take pictures in the dark.

It also means faster shutter speeds. Try this: have someone wave at you indoors and, with your camera set to 100 ISO and with its flash turned off, take a picture. You will see this:

Now set the camera to 1600 ISO.

That means 16 times higher sensitivity (four stops) – which means 16 times shorter shutter speed, as the camera does not need as long to gather the same amount of light; hence 16 times less time for motion blur.

So now you get this:

The price? Noise. More noise, just as when you turn up the radio when you are hearing  a weak signal. The volume will  increase, but so will the noise. In photos, we used to call this “grain”, after the larger silver crystal grains that captured the light on negatives.

But usually, that is a small price to pay if you want to avoid blurry hands.