Think of Photoshop layers as stacking pieces of transparent papers one on top of another to create the final image. In addition to your “normal” layers there are also special layers that can interact with the layers below. This is useful to create photo montage, light adjustment, color corrections and anything else you can think of, but first you will need to understand how they work.

Blending modes are separated in 5 different categories,

Darkening (use to darken or fix overexposed photos)

Lighting (use to lighten or fix underexposed photos)

Contrasting (is a combination of both Darkening and Lighting sets)

Comparing (use to align and compare photos)

Coloring (use to fix hue and saturation)

The first two modes are not categorized - 

Normal blending is selected by default, it does not have any special feature and should work just as expected.

Dissolve mode will only work where there are semi transparent pixels, all semi transparent pixels are turn into solid pixel noise, the density of the noise is depending how the level of transparency. The following sample shows the word "Dissolve" with blurred applied(semi transparent edge) two different times. The sample on the top is on a Normal blending layer and the bottom sample is in Dissolve blending layer.

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The first set of the blending mode deals with “DARK” pixels. It is helpful to correct and darken any parts of your photos.

Darken – Compares the Darken layer to the base layer and keeps the darker pixels of the two. In the sample below, since the plants in the foreground are the only things that are darker than the Base layer, only the flowers are kept and the rest of the pixels become transparent. If you shoot your subject against a bright background, you can quickly lay it on top of a different background.

Multiply – Combine the blending layer with the base layer by “multiplying” the color information which gives you a darker final image. This is great for fixing overexposed photos and the most commonly used mode of this set. Duplicate the layer and set the top layer to Multiply and you will end up with a darker, better exposed photo assuming you used a photo that was overexposed such as the example below.

Color Burn – The blending layer uses the brightness information to increase the contrast of the base layer, the darker the pixel the higher the contrast. The sample shows three shades of gray, the darker the gray shade, the darker and higher contrast the final image becomes. White does not affect the image. You can use paint brush and paint over a small section with different shades of gray to achieve the feel you want.

Linear Burn – The blending layer uses the brightness information to increase the darkness of the base layer, the darker the blending layer the darker the result. The sample shows three shades of gray, the darker the gray the darker the final image becomes, the contrast remains the same. White does not affect the image. You can use paint brush and paint over a small section with different shades of gray to achieve the feel you want.

Darker Color -

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The following sets will help brighten and fix underexposed photos. It has the exact opposite function as the last set.

Lighten – This is opposite of Darken, it compares the Lighten layer to the bottom visible layers and keep the lighter pixel. Darker colors are omitted.

Screen – This is opposite of Multiply, it multiplies the inverse information to create a lighter final image. It is perfect fixing underexposed photos and the most used mode of the brighten sets. The sample below shows the blending layer and base layer is the exact same photo while blending layer is set to Screen, the final image is brighter and better exposed.

Color Dodge – The blending layer uses the brightness information to brighten and increase the contrast of the base layer, the brighter the pixel the higher the contrast . The sample shows three shades of gray, the lighter the gray the brighter and higher contrast the result becomes. Black do not affect the image.

Linear Dodge (Add) – The blending layer uses the brightness information to increase the brightness of the base layer, the lighter the blending layer, the brighter the result. The sample shows three shades of gray, the lighter the gray the lighter the final result, contrast appears to decrease. Black do not affect the image.

Lighter Color

Continue to part Two of this tutorial...

This is part of my tutorial set. Please visit the TUTORIAL PAGE for a list of all the tutorials.

If you need to quickly select an area of similar color such as replacing the sky or a green screen Magic Wand is your tool.

Activate Magic Wand by hitting (W) key or select it from the tool box.

Magic wand works by selecting similar colors in your photo, so if you have a photo of  a model in front of a solid color background you can use magic wand to automatically select and delete the entire background. Of course you might not always have the luxury to use a nice clean background so here are some tools to make your life easier.

Above is the first half of the magic wand menu. If one click is not enough to cover your entire selection you can use the add (or hold Shift while selecting), subtract (or hold Alt/Option while selecting), or create intersection(or hold Alt/Option + Shift while selecting) icons to help you expand and perfect your selections.

Tolerance value determined how much similar color Photoshop should pick up. If the object you are trying to select is fairly evenly toned you will only need to low Tolerance value to work, but if your background is poorly lit and has too much variation, you might want to go with a higher value. The only problem with setting high Tolerance is that you might end up selecting colors you do not need so it might be better to set the Tolerance low and use the Add/Subtract function.

Anti-Alias, it will make the edge of your selection a bit softer to create the illusion that the edge is smoother.

Contiguous selection will only select area that are connected. See the example below, I tried to select the white background with Contiguous on, it does not select the white background isolated by the pink heel and the black heel. If I turn contiguous off, it now selects the isolated area but also everything else that looks like the white background such as the highlight area on the heel.

Turning Contiguous off might save you a few click but you will also risk selecting areas you do not need, you are better off leaving Contiguous on and use the Add/subtract selecting technique discussed earlier.

By default Sample All layers is turned off, magic wand will only work off of the active layer, even though you can see the layer below magic wand will still ignore it. Once Sample All Layers is turned on, magic wand sample everything that is currently visible.

In addition to Tolerance, you can also change how much color magic wand will consider as similar by changing the Eyedropper sample size.

Select Eyedropper tool (I), under the option bar, choose a bigger sample size.

A 31x31 average means it will look at the closest 31x31 pixel area and use the average value of that entire area instead of sampling one color pixel. It will be useful if the object has a lot of tone/value variation.

You can refine the selection by expanding, contracting or softening the edge and even automatically retrace the edges using the Refine Edge Tool. It is available in most selection tool such as lasso or marquee, you can also find it under the Menu Select-Refine Edge or with shortcut Alt/Option+Ctrl/Command+R. Read my article about Refine Edge here.

This is part of my tutorial set. Please visit the TUTORIAL PAGE for a list of all the tutorials.