Friday, August 8, 2008


I'd love to discuss clipping. Why do you (Stephen) hate it so much? How do you (Dan and other readers) feel about it?

Though I admit I'm exerting no control over when my photos clip, sometimes I like the sense of overwhelming brightness.


Stephen said...

First, I should say that I think I am overly sensitive to clipping because it has plagued many of my photographs and because I have tried to develop methods and tools to minimize its effects.

I dislike it because is looks unnatural. This can be used intentionally to create a particular aesthetic, but if it does not fit with the purpose and/or subject matter of the photo, it can be jarring.

The worst effect of (unwanted) clipping is color distortion due to the channels (red, green, and blue) clipping at different points. This is most commonly seen in the bright, electric cyan color of the sky in many digital photos. This happens when blue and green reach their maximum values (255) before red does. Since the ratios of the colors are wrong, the resulting hue is wrong. If a photo of an area of constant hue and varying brightness (like the sky) contains points where each of the channels clip, there will be bands of different hues in the photograph that do not exist in nature.

Clipping does not hurt black and white photos as much since hue does not matter (though gradients can be effected in a similar way). However, black and white photos can contain large areas of flat white as a result of clipping. This also looks unnatural, though it can of course be used intentionally. It is easier to compensate for clipping in black and white photos and minimize its effects through editing. Levels, curves, and gradients may be effective, depending on the situation.

Film photography does not suffer from clipping the way digital does. Of course, bright areas on film can be blown out. The difference is in the shape of the response curve at its top end. Digital has a corner; film has a curved shoulder. This means that as the image on digital gets brighter and brighter, the value of the pixels keeps climbing at a constant rate until it reaches its maximum (255). On film, as the image gets brighter and brighter, the increase in the film's response slows down, and the film gradually reaches its maximum. As a result, film can continue to respond at higher levels of brightness and there are no hard edges where it clipped.

Nathan L said...

Okay, I think my brain just clipped in the middle of paragraph #4.

No really, that was good stuff.