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Your histogram is lying

The histogram is our most reliable tool when it comes to proper exposure, we watch it closely on live view, expose to the right (ETTR) like they told us to, because there is noise hiding in the shadows etc. Now what if I told you that histogram is (sometimes) lying to you and you’re actually overexposing without even noticing?

I mentioned this on Chris Sale’s YouTube feed and it seems it isn’t just me who’s noticed this seemingly odd behaviour.

Look at this histogram, everything seems in order here, right?

However, if we look at the individual channels we can clearly see that the reds and blues are clipped:

How is that possible, why isn’t that reflected in the monochrome histogram, which is the average over the R, G and B channels? Because green dominates the picture and dwarfs the contributions from red and blue in the highlights. If you were to take a picture like this one (which is just for demonstration purposes, really), you’d really want the blues to be properly exposed, wouldn’t you?

There are many more situations where this can really bite you. Take birds in a clear blue sky, sunrises and sunsets and so on. Don’t fall into this trap, clipping cannot be undone in post.

Always check the individual colour channels after you’ve taken an image, don’t rely solely on the histogram in the live view.

2 thoughts on Your histogram is lying

    • You’re welcome mate. Currently out and about for my upcoming video where I’ll be shooting the lunar eclipse. There’ll be some tips in there, too, not just relating to night sky photography.

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