Shapes and Contrast, 2

Without Contrast Your Image is a Blank Slate

Can you trust your eyes? Another  in a series on shapes & contrast – and visual perception.
Your eyes can be fooled – easily. Often it’s not critical unless you see green as red and vice versa and then traffic lights may be a problem. Although not as critical as running a green? light, color and tone confusion can cause problems when editing and printing images. We discussed this extensively while presenting various color topics in the first of our 4-C’s – Craftsmanship.
The previous shapes & contrast article demonstrated that a shape’s apparent color depends on the color & contrast of the area surrounding the shape. Identical colors may appear to be different from one another. In this article, we’ll see how – even in the absence of color – we can misjudge what we see. The eye can be fooled in terms of tonal differences very easily as shown here.
The question is – which oval is the brightest? (See below)

You probably said – bottom right. Wrong! All three are identical. They are all pure white. You can prove it to yourself by copying this image

  • Right click the image
  • Choose Save As from the drop down box
  • Save it to your computer

and checking it in your image editing software. For Photoshop Elements –

  • Open the saved image
  • Check with the color picker as shown below

and this is what you’ll see. Note that the color picker is sampling the (apparent darkest) oval in the upper left corner. Look at the picker’s readout – the oval is pure white.
This same phenomena was shown in a 5-minute video in this earlier color & white balance primer from the craftsmanship section. It doesn’t take 5 minutes to illustrate the point – just a glance will do it.

In addition to white balance considerations during image editing, the phenomena has implications for your images as captured in the camera. The confusion over the tone of the upper left oval is caused because of its relatively low contrast against its surrounding environment. OK – I love soft moody images, preferably black and white, shot in rain and fog – a situation that cries “low contrast”. Such conditions have a definite impact (not necessarily bad, but an impact nevertheless) on my images for the same reasons illustrated in our three-white-ovals example. Just sayin’….
Go here for Part 3

0 thoughts on “Shapes and Contrast, 2”

  1. Very interesting, I will try something like this over the weekend and let you know results.

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