Solving Over Exposure with Layers

OK, vacation's over and it's time to get back to work. I apologize for having several post-free weeks. My wife and I were traveling the western US and enjoying the Grand Canyon and other sights. The current post features a photo taken in Arizona.

Here is a photo that sometimes happens. The meter emphasizes the wrong area, the photographer sets the wrong shutter speed or f/stop and the photo is drastically over exposed.

 Like this:

Solution possibilities are many. If you've taken the shot as a raw image you may be able to just reduce the exposure in processing and save it. If you are familiar with "levels" and adjustment there could also work.

Here I show another possible help that you may not be acquainted with. Most photo editors allow you to work with layers. With layers you can, among many other things, combine two images. A building and a sky for example to replace a dull sky with a more interesting one. I will probably do that in a later post for those who haven't tried it. Here I will use another layer function that many are not aware of. In a photo editor (here I will use Photoshop Elements) if you place a photo on a layer on top of another photo you will only see the top photo. So why have a second layer? If we cut a hole in the the top layer the bottom layer will show through. If we change the reduce the opacity of the top layer to less than 100% the bottom layer will also show. There is another option that is seldom used by those new to photo editing. At the top of the Layer's Pallet you will see the word "Normal" but if you click on "Normal" you will find 24 more "Layer Blend Modes" which control how a layer acts on the layers below it. In Normal mode the photo just lays on top of the layer below. We are going to use another of the 25 available modes it just a moment.
First I've copied the bottom layer. Typing [Ctrl J] creates a copy of the current layer and places it on top of that layer. In this case it becomes "Layer 1" and will show no change because it is just laying on top of the original. Now click on that word normal and choose "Multiply" and suddenly something has happened. The value of each pixel has been multiplied by the value of the pixel on top of it and becomes darker. Imagine a value of 2. 2x2=4 it's now twice as dark. The value 4, or 4x4=16 and it's now 4 times as dark. The Multiply mode takes a flat looking image and darkens it more in darker areas than it does in light areas, exaggerating the differences and darkening the photo as a whole. Sitting on Layer 1 and typing [Ctrl J] again creates the layer pallet you see here. "Layer 1" has been copied and has created "Layer 1 copy" has been created. Since Layer 1 was in the Multiply mode the copy is also and now 2 has become 2x2x2=8 and 4 has become 4x4x4=64 and the exaggeration has become much greater. Keep in mind that 1x1x1=1 so the brightest areas are still as bright. What we have created is this:

It's not perfect, and a correct exposure would be better, but we have created a usable image from one that was very pale.

If you want to experiment further, placing a copy of an under exposed image (too dark) on top of itself and setting the blend mode to "Screen" will lighten the image in a similar manner and you may be able to salvage it as well.

Thank you all for reading this and it's good to be back on the blog. See you  soon!

Why Some Editing Takes Practice

The photo here is of a building that houses a very favorite restaurant of mine, the Blue Dog Cafe in Snow Hill Maryland, USA. It is an HDR image composited from 5 exposures. It doesn't matter how many exposures I'd taken the power lines I didn't want, and this is the tale of getting rid of them.

I won't call this a tutorial as step by step instructions would make a much longer post than I usually do. Here, though, are a few ideas to help you. First, if you've never attempted something like this, removing unwanted items in photos has almost nothing to do with removing anything. We need to determine what is behind the item we want to get rid of, find something close elsewhere in the photo and copy it on top of what we want to disappear. Notice we don't remove we cover up.

An obvious tool in current software are those called "content aware" Photoshop and Photoshop Elements both have versions of this and when it works it's as though a miracle has occurred. The "Spot Healing Brush" tool is available in both programs. Select the tool and a fuzzy brush, hold down the left mouse button and keep painting until you've covered the object you want to disappear, now release the mouse button and wait. After a few seconds the object is gone, replaced by what the software has calculated to be what was probably behind it. If it worked you are done. If it almost worked but not quite you can grab the "Clone Stamp" tool and repair the areas where the "content aware" has failed. If it fails miserably (not uncommon) just click the Undo button or type Ctrl Z and try a different way.

Wires that cross plain blue skies, for example,  can be covered with a copy of nearby plain blue sky, easy to do. If the wire passes in front of clouds you will have to use the Clone Stamp tool to copy bits of the cloud over the wire until it is covered and the cloud still looks real. In the Blue dog photo the wires pass in front of bricks. Since the bricks have a uniform pattern you can copy adjacent brick carefully over the wire and it will seem to disappear. You will have to be sure that the bricks you paste align with the pattern of the rest. A second problem is apparent here the heavy cable casts a shadow on the bricks just above the bottom of the windows and a slightly different method will help here.

Using the Clone Stamp tool exactly as before with one exception. The tool Mode is, by default, set to "Normal" which means anything you copy is pasted exactly as the original. This time change the mode to "Lighten" and it will only past pixels that are lighter than those already there. The shadow is the same brick as the surrounding brick it is just darker so the lighten mode will only affect where there is shadow.

Just for fun I decided to remove the reflection of the telephone pole from the window. Here I used the Clone Stamp tool to copy sky and foliage over the pole and wires.

One problem area I have not mentioned is the areas of curved brick over the windows which the wires passed in front of and were difficult to repair. Note that the right most window has the least interference with the top curved row of bricks and these can be copied and pasted over the other windows. Using Edit>Transform>Distort feature the copy can be re-sized and distorted as necessary to make it match the size and angle of the other window tops. A copy of bottom curved row of brick from the second window from the left can similarly be copied and pasted to cover the bottom rows that have wire in front of them.

None of these repairs is easy or quick to do. Being familiar with the tools a practicing will of course speed up the process considerably. The first time, plan on spending several hours doing this and                                            copy the photo to a new layer (Ctrl J) so that you can always go back and start over easily. In Photoshop learn to use the history pallet to allow you to go back to an earlier spot and in Elements the undo can be used repeatedly to move you back in editing time.