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View Full Version : Excessive contrast is a digital shooting mistake


zafrina23
01-27-2007, 05:47 AM
If you've shot on days with harsh sunlight, you've probably noticed that many of your digital images exhibit extremely high contrast. Such pictures include dark shadow areas and ultra-bright highlight areas. Excessive brightness is the most serious problem, with "burned-out" or "blown-out" highlights that obscure detail in, for example, a bride's white gown or a snow-covered hillside.

With sophisticated image-editing software such as Microsoft Digital Image it's easy to solve certain technical problems. However, it's almost impossible to fully correct blown-out highlights. While these can be darkened, you cannot add detail or texture that was not recorded by the image sensor.

staereo
01-27-2007, 06:35 AM
You should 'expose to the left.'

That is, when shooting in RAW, expose your orginal shots a stop or so underexposed, and then adjust the EC in your conversion software. The most data is contained in the lightest elements of your image, before being blown out.

So, by underexposing, your spreading that data across a more centralized exposure area of your image's histogram, AND, you avoid blowouts. You may lose a little bit of data in the shadows, but because dark areas contain the least amount of levels of data in an image, you lose the elast amount of information when your images data is clipped at the darker areas rather than the lighter areas.

Its all because digital is a linear exposure, when chemicals create a nonlinear exposure and have far less defined points of image loss.

Bruce

TomodachiFriend
01-27-2007, 07:45 PM
But you forget that most consummers prefer images with very saturated colors and lots of contrast. I see it, not only when people look at pictures, but also when they're shopping for TV's and computer screens.

The-Real-Link
01-27-2007, 09:32 PM
That's a good point. Normally I'll try a couple test shots beforehand but turning the exposure down a few notches is normally enough to avoid having a ton of the image hit extremes it seems. Thanks for your input on that Bruce.

Av4rice
01-29-2007, 02:01 AM
Personally I love high saturation and contrast, though maybe I don't use it to the extent you're warning against (maybe I do?)

Going for underexposure at first is an interesting idea... though in my personal experience it's pretty rare for me to get an upper-end blowout and more common to get something too dark that I only got one shot of and that looks terrible due to noise from exposure compensation.