Using the Clipping Indicators in Lightroom
If you don’t know what the histogram is, it’s that graph looking thing in the righthand panel in Lightroom. That’s a topic for a whole nother day. But those triangles in the top left and top right corner of the histogram as clipping indicators. They help you show when “clipping” occurs – i.e. when a pixel is displayed as pure black or pure white because it lies outside the range of light that your digital camera and software could process.
Let’s look at an image and see how these things work…
An Underexposed Image with Lots of Black
Here’s an image for us to work with. It comes from the “Heat” Fashion Show at William Paterson University in March 2010. The picture was taken towards the end of the evening, when we were trying to get a few cast group shots.
The lighting wasn’t so great, because the black curtains were swallowing up any kind of bounce, so the image came out a bit underexposed. It’s a good candidate for some post processing work to brighten the image, but it’s also a good candidate for using the clipping indicators.
Click the Arrows, Turn On the Clipping Indicators
In this picture, I clicked both of the clipping indicators to turn them on. Notice the weird blue area on the curtains? What Lightroom is telling me is that the blue-ish area has no definition in it. It’s just plain old black.
The problem here is that cameras can only capture a certain range of light, and software can only process and display an even smaller range of light. Your eyes might be able to discern some detail in the shadow of those curtains if you’re there, but the camera can’t see that detail and still keep the people reasonably well exposed.
What happens is black clipping. The camera (or the software, in this case Lightroom) gives up and just displays a black pixel. It’s hard to tell whether a pixel is pure black because it’s been clipped or if it’s just really, really dark. So turning on the clipping indicators makes it easy for you to see what has been blacked out.
Turn Up the Exposure
Now let’s say I started brightening the image using the Exposure slider. For illustrative purposes, I took this way too far.
I cranked the exposure up to 11, err, 3 stops. Notice all the new red stuff? That’s Lightroom telling me that white clipping is happening. All those red areas are completely blown out – they’re pure white pixels that no longer have any definition.
In other words, I might want to tone down the exposure slider down a tad to something a little more reasonable… like + 1 stop.
So When Is This Useful?
So why would you want to use the clipping indicators? Because you have to make some trade-offs in photography. In most images, including one like this, there are going to be either areas of blacks or areas of whites (and sometimes both). But in the original image, nothing was blown out – there was no pure white.
Since I took the image in RAW, the camera actually stored a larger range of light data than Lightroom could process and display on my screen. I can use the Exposure slider to shift this range to the right (and make it brighter). By having the clipping indicators on, I can slowly drag the exposure slider to the right until some of the white areas are just becoming blown out and then back it off a tad. That way I brighten the image as much as I can without blowing out more detail.
Likewise, I might have an image where small bits of it fall into shadow. The black clipping indicator will bring out those spots for me to see, and I can slowly drag the exposure slider to the right to bring out the detail in those shadows.
Of course, sometimes you can’t bring out detail. Sometimes, it’s not a matter of Lightroom limiting the range of light… it’s your camera. Notice how the blue areas shrunk a little bit when I increased the exposure, but they were still there? Cause there was simply too little light. Likewise, you’ll sometimes get really bright areas of blown out highlights that are going to stay pure white – no matter what you do with the exposure slider. The clipping indicator helps you make slight adjustments when your in-camera exposure is close but not quite spot on.
Tell us what do you think.