READING THE HISTOGRAM - The Channel Histogram

The Histogram reads across from black (left) to white (right) / 0 to 255 (256 values no matter how many color are in your picture – 256 no matter if you are working with 8,16, or 32 bits).

In the top Channel Histogram we can see the details lost in the brightest and darkest areas of the image. When the Histogram Channel View is set to Luminosity instead of the default RGB a spike to the right edge of the histogram would indicate that white is prevalent in the image the image would lack highlight detail.
As we can see above that is not so in this one. In fact we can see that we are lacking spikes on the bright side and I would desire more there.

A spike on the left edge would indicate the image contains areas of solid black. The taller the spike on left edge then the more prevalent black is within an image and the less shadow detail the image contains.

Spikes to the left and right edge of the histogram indicates that either the exposure settings on the camera caused a loss of shadow and/or highlight or this loss was caused by an aggressive application of Photoshop (post processing).
In summary at looking at the Channel Hitogaram of this picture I read that when I took the picture it was somewhat underexposed (saying this knowing that post processing has not taken detail that is important to speak of here). However, it is not underexposed to the extent that shadow detail was hurt enough to ruin the picture. There are few very high peaks at the left side of the histogram and none on the left edge.

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