December 23, 2009

Cypress trees and streaming sunlight

click photo for full-size image
photo by Donald Kinney

Well, I grew up in the Monterey/Pacific Grove/Carmel area, so the San Francisco fog was nothing new to me when I arrived a little over 40 years ago.   Both areas also have Cypress trees -- and the combination of fog and artful trees can make for some interesting compositions.   Throw in some streaming sunlight for fx and you've got a pretty picture!

click photo for full-size image
photo by Donald Kinney

O.k., here's your Histogram lesson (for the second photo, just above) -- whether you want it or not!

The Histogram is a graphical scale (from 0 to 255) representing all the tones in the image.   Notice that gap on the left side?   This shows the low values don't go all the way to pure black in the original image -- so I "expanded the tones to fit the scale" which gives some richer dark tones in the finished photo.

This what the Histogram looks like after the range of image's blacks is extended.   The tones reach all the way to the left edge of the scale.

Normally you might consult the Histogram more often when correcting slight under-exposure.   In that case a similar "gap" appears on the right side of the scale -- showing that no pure whites exist.   An underexposed photo will have a graph that doesn't extend all the way to the right edge, and the adjustment for high-values is made by extending the scale to the right.

Now, do you notice that little "spike" at the right edge of the scale?   Well, that's the beginnings of a blown-out photo -- and there is nothing worse than a blown-out photo if your intentions are to produce a technically perfect photo.   In this case, the blown-out tones are not too intrusive, so I didn't bother trying to correct them.

Keep in mind that under-exposure is easier to correct than over-exposure.   Also remember that using too much correction on low values can increase noise to an unacceptable level.

[[[and Jan Bell, if you're out there, silent as usual, thanks for showing me this stuff a couple years ago]]]

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Rhett Redelings said...

These are both very beautiful although the second is definitely my favorite of the two. Any chance of seeing the original, uncorrected version to go with the histogram lesson? I'm a bit lost when it comes to the whole histogram stuff.

AphotoAday said...

HI RHETT -- Well, just imagine the photo with the darkest colors just a little bit more gray... (((am too lazy to make a sample photo, but I think this gives you the idea)))

When someone showed me about Histograms I was an unwilling student at first, but now I trust them more than I trust my eyes when evaluating a photo...

bath mate said...

As always an excellent posting.The
way you write is awesome.Thanks. Adding more information will be more useful.


Marcie said...

Love the light!!! Best wishes to you and yours..

Jane said...

Nice lesson. Well done.

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