Brightness the colour snatcher

It's a simple statement, but one oft ignored; adjusting brightness, should not affect colour lightness. Try achieving that in Paint Shop Pro or Photoshop, best of luck.

Most image editing programs operate on colour in its raw red, green and blue components. This approach, though no doubt convenient, makes it very difficult (practically impossible) to adjust brightness without changing the characteristics of the colour itself. This is why when you adjust brightness or contrast in Photoshop for example, this affects the colour lightness, and often the hue and saturation in an adverse fashion, in addition to the brightness of each of the pixels. This isn't what you want, and it isn't what you asked for.

To modify the brightness of a pixel correctly, then you need to first transform the pixel into a colour space where brightness, lightness, hue and saturation are all easily separable, uniquely modifiable and then reconstituted. This, is what Imagina does.

The CIELAB colour space is used to perform this magic and math behind it all can be quite intensive, but the results speak for themselves - we've had to work hard to get this right for you. But you don't need to know any of that now do you? What all this means in simple terms is that you can rely on Imagina not to destroy your image like other competing products do.

Brightness incidentally, is not the same as luminance, something that nearly all image-editing software falls foul of. What this means to you is that when we're talking about brightness, we talking about it with up to 10 times more accuracy than any other software you'd be likely to use. You can rely on us to get it right for you, and here's why.

Let's look at a hard example where we've used a brightness curve on a image to alter its mid-tones - shadows and highlights are altered here too, but less so due to the shape of the curve.

Our sample image before any alteration.

Now the image brightened with Photoshop.	And the image again but this time brightened with Imagina.

Compare the front of the upper car where a lot of mid-tones are gathered. See how the algorithm that Photoshop uses "lightens" the image rather than brightening it, turning orangey-grey into almost pure grey. This distinction is important. Lightening an image adds more grey into the colour until finally you would end up with pure white. Brightening on the other hand, preserves the balance of colour and simply brightens that colour.

Now the image darkened with Photoshop.	And the image again but darkened with Imagina.

When darkening an image, Photoshop's algorithm makes things even worse. Take a look at the front of the upper car again. Photoshop has really exaggerated the vaguely orangey hue into highly saturated orange instead, not at all what you wanted I'm sure. Now compare that with Imagina again, where it has simply made the existing colour darker. This, is what you want your image-editing tool to do.