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In this guide:

Free online Photoshop tutorials and info:

Everything Photoshop:

Recommended Photoshop books:

Free online photography tutorials:

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Photoshop - A Beginner's Guide (continued)

  • This guide continues from...
  • Page 1

The Paint tools

Brush tools, notes on Opacity and Flow

Options bar
Most of the time I use the paint brush tool, and this is usually to paint black, white or grey onto a Layer Mask. In other words, I am not creating a work of art with it.

Some really useful shortcuts for these tools will be found here.

The most confusing thing I encountered was the meaning of, and differences between, Opacity and Flow.

It really helps to understand that a brush stroke using a mouse lasts as long as you hold the mouse button down. If you wipe to and fro across the same area with the mouse button held down, this is still only one brush stroke. Are we clear on that?

Opacity is the opposite of transparency. Low opacity is highly transparent, and vice versa.

The opacity setting limits how "non-transparent" the effect of one brush stroke can be. Remember that a brush stroke lasts for as long as you hold the mouse button down, whether or not you wipe over the same area.

Flow, on the other hand, determines how quickly the paint leaves the brush, but on any one (possibly very long) brush stroke the eventual effect is still limited by the opacity setting.

Here's a pop quiz:

What happens if you set opacity to 50%, flow to 100%, and paint black over a white area with the mouse button held down?

Yes, you get an area that is 50% grey, which I think of as "half-black". So far, so good...

Now let go the mouse button, then do the same stroke again. What should happen?

To your surprise (or mine, anyway) the result isn't pure black. This is because you have just increased the "blackness" of that area (which was 50% black) by another 50% of the original 50% (i.e. by another 25%), and so you now have 75% black.

Now change the flow to 10%, and repeat all of the above experiment.

This time the paint build-up is much slower. If you let go of the mouse button (finish the stroke) early, then the results will be much more transparent (lighter grey) than the previous time. But if you go on long enough (still holding the mouse button down as before), then the final effect will be exactly the same. In other words, your first brush stroke, if you go on long enough, can only reach 50% transparency.

Now turn on the air brush capability option (sorry, it should have been off before). You will see that this is also affected by the flow setting, as you would expect.

Try it! It's really the only way to learn about these settings.

For more information on the brush tool options, see here, and for more on Photoshop brush tools generally see here.

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Recommended training for using the Paint tools

Gold Award symbol As part of your "Boot Camp" training, I strongly recommend that you complete all of Sue Chastain's excellent tutorial on using the Painting Tools. The topics covered through exercises include:

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Notes on the Gradient tool

Gradient options
I am not going to tell you everything about this tool! Click the image above for many links about it.

I use the Gradient tool (G) mainly for creating Masks or Layers that typically have a shading from White to black, from a colour to black or from grey to black, in either a linear or radial pattern. I use these in connection with the various Blend Modes, or to set up a graduated neutral density filter.

gradient and image This particular example is a Layer containing a radial gradient from mid-grey to black (mouse-over to see the image that it produced when blended with the lower Layer using the Soft Light Blend Mode).

The gradient line was drawn from the centre of the flower to just beyond the rim of the flower.

From where the gradient line stopped to the edge of the image the gradient fill is solid black.

The initial effect of the Blend Mode was too strong, so I dialled back the opacity of the top Layer to about 60%.

Here are some notes about things that I found confusing when I first used the Gradient tool:

Gradient options

swatches The left-hand pick list brings up a list of default swatches. It doesn't always look like this - that's because the first, second and last of these swatches reflect the current foreground colour.

The first swatch goes from foreground to background, the second from foreground to transparent (if the transparency box is ticked), and the last (which I don't use) produces stripes of foreground colour against a transparent background (again, if the transparency box is ticked). The other default swatches use preset colours.

The current swatch is the pattern in the left-hand box. Click it to get the Gradient Editor, if you want to create more swatches. I haven't needed to, yet.

The next set of buttons select the various Gradient Types, the first two being Linear and Radial.

I don't use the Mode or Opacity settings here. That is because I always use a Layer or a Layer Mask when I am creating a Gradient, and the Layer has its own settings for Mode and Opacity.

Reverse does what it says, effectively flipping the swatch the other way around.

Dither is something I always have checked. It makes the gradient smoother.

Transparency is also something I always have checked. If you uncheck it, the transparent parts of the swatch are replaced by the foreground colour. I haven't found a use for this, yet.

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Notes on the Clone Stamp tool

Gradient options
I am not going to tell you everything about this tool! Click the image above for many links about it.

I use the Clone Stamp tool (S) mainly for removing unwanted stuff from photographs.

On the Options bar, you have the usual controls for selecting brush size/type, opacity, flow and airbrush on/off.

I don't change the Blend Mode in the Mode box, because I haven't found a need to, yet.

The important thing is the aligned box:

  • When it is checked, the relative distance between the pickup location (see below) and where you are painting now always remains the same. You use this to copy from one area to another, even if you let go of the mouse button and come back later.
  • When it is unchecked, you start off from the same pickup location each time that you let go of the mouse button and then hold it down again for another paint stroke. You use this to copy the same pattern to many different places.

You set the pickup location by alt-clicking (PC) or option-clicking (Mac) with the mouse. The great thing is that the pickup location can be in several different places:

  • If you uncheck the Use All Layers box, you can pick up from any active Layer, otherwise you pick up from all visible Layers.
  • You can also pick up from this document, or any other open document.

  • Some tips...
  • Picture of Light Bulb I suggest that you never have the source image and the image you are modifying in the same Layer. If the source image and the image you are modifying are the same, then create a new transparent Layer above the source image and copy from the source image to the new transparent Layer (you could even lock the Layer containing the source image).
  • Apart from making it easy to go back to what you had before, and letting you turn the visibility of the top Layer on and off to compare the difference, this prevents the pickup point wandering into an area that has already been modified, which can sometimes matter.
  • Picture of Light BulbIf you are doing a lot of work with brush strokes, and you have a reasonable amount of memory, you might want to increase the maximum number of History States in the History Palette. You can do this by Edit > General Preferences (Ctrl+K) and then change to a number such as 90.

  • An alternative to the Clone Stamp: the Healing Brush
  • If you want to fix an area using the textures around the pickup point but keeping the tonal characteristics of the area that you are fixing, then try using the Healing Brush.
  • The Healing Brush (J) works very similarly to the Clone Stamp tool. Just be aware that there may be a noticeable delay after you paint, before the effect appears. There is some serious intelligence at work!
  • One difference from the Clone Stamp tool is that the above tip on creating a new transparent Layer won't work with the Healing Brush. This is because the Healing Brush isn't just adding information, it is blending two areas together. If you don't want to modify the original image, then create a duplicate Layer.
  • You will find an excellent tutorial about the Healing Brush here.

Working with colours

Colour Spaces and the Colour Picker

colour boxes The best way to become familiar with the various Colour Spaces that Photoshop uses is to play around with the Colour Picker tool, which you bring up by double-clicking the foreground or background box in the Tool Palette or the Colour Palette.

color picker

You can pick a colour using one of the Colour Spaces (see below). If you click a radio button in one of the first three Colour Spaces (in this case, L in Lab colour space), then that value applies to all of the colours in the window. You can use the vertical slider to get a different value and a different set of colours. The other two values for the same colour space (a and b in this case) correspond to the left-to-right axis in the colours window and to the bottom-to-top axis in the colours window, respectively. You can select a colour by clicking anywhere in the colours window.

Alternatively, you can enter values into any of the colour space boxes.

colour boxes You may sometimes want to set up a colour that is 50% grey, for use with the Blend Modes, if it hasn't already been set up for you. The quickest way to do that is to type 808080 after the # in the box near the bottom right (then check out what happens to the other numbers).

You are also given an option to select 50% grey when you use Edit > Fill.

You get warnings if the selected colour is out-of-gamut for printing or for the web, and you can confine the colour choices to only web-safe colours. For more information, click the above image.

Here is a brief summary of the various Colour Spaces:

Hue, Saturation, Brightness (HSB)
This describes a colour in terms of its Hue (the actual colour), its Saturation (the intensity of the Hue), and its Brightness (the relative lightness or darkness of the colour).
You can't work in HSB mode, but you can use it to pick colours. Curiously, in Photoshop you can adjust and replace colours in the related but slightly different colour space HSL.
More >>
Lightness, a, b (Lab)
This colour space, unlike RGB and CMYK, approximates human vision (meaning that equal changes in values should produce equal changes in perceived colour). Its advantages are summarized here.
This space describes a colour in terms of its Lightness (the value in the image that gives it detail, equivalent to the relative shading from black to white in a grey-scale image), a (a scale of Green to Red values) and b (a scale of Yellow to Blue values).
You can work in Lab space (with some limitations on functionality).
  • Some easy ways to take advantage of Lab Colour...
  • Because the Lightness channel contains no colour information, it can often be beneficial to carry out sharpening and other contrast adjustments only on this Channel.
More >>
Red, Green, Blue (RGB)
This is the most common Colour Space, and the one that you usually work in.
The different colour components combine in the way that light does. Red, green and blue in equal proportions would combine to make grey or white.
More >>
Cyan, Magenta, Yellow, Key (CMYK)
This Colour Space has to do with the technologies of printing. Inks combine subtractively, as they absorb light. In practice, a certain amount of black ink must be also used in order to get correct printed colours. (The "K" in CMYK is commonly associated with the last letter of "black", but it actually has to do something related called a key plate).
In general, you work in RGB, and keep all your master images in RGB, converting to CMYK (if you need to) only when preparing for printout on a particular printer. See [P7A] for details, and you will also find many links on this subject here.
More >>

Here is a useful summary of RGB and CMYK from the Computer Desktop Encyclopedia:

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Notes on Brightness and Complementary Colours

RGB colour values (with 8 bits per colour) range from Black (0,0,0) to White (255, 255, 255).

Bright red, for example, is coded as (255, 0, 0).

I find it useful to invent a new term, Brightness Factors:

The Brightness Factors of a colour (not the same thing as the colour's Brightness, see below) are what you would get if you divided each colour value by 255, producing a fraction from 0 to 1. The Brightness Factors of Black are (0, 0, 0), for White they are (1, 1, 1), for mid-grey they are (0.5, 0.5, 0.5), and for bright red they are (1, 0, 0).

50% bright grid The Brightness of the colour, expressed as a fraction from 0 to 1, is actually the arithmetic mean (a simple average) of the three Brightness Factors (more >>).

All of the colours on the right have a Brightness of 50%. The first square is mid-grey whose Brightness Factors are (0.5, 0.5, 0.5). However, the colour next to it has Brightness Factors of (0.75, 0.75, 0), so that two of its colour components (red and green) are more than 50% bright.

color grids In fact, Red (1, 0, 0), Green (0, 1, 0) and Blue (0, 0, 1) all have a lower Brightness than 50% grey (0.5, 0.5, 0.5), even though it may not always appear that way to the human eye.

On the other hand, Yellow (1, 1, 0), Magenta (1, 0, 1) and Cyan (0, 1, 1) all have a higher Brightness than 50% grey, because each of them is comprised of two additive colours (mouse-over the colour block to see the difference).

  • Complementary Colours
  • You can see that if we start with White (1, 1, 1) and subtract Red (1, 0, 0) what we get is Cyan (0, 1, 1). (We are just subtracting the first numbers for the Red components, then the second numbers for the Green components, then the third numbers for the Blue components.)
  • If we do this the other way round, subtracting Cyan from White, we get Red.
  • Because of this, we say that Red and Cyan are complementary colours.
  • For the same reason, Green and Magenta are complementary colours, and Blue and Yellow are complementary colours.
  • There are many times in using Photoshop, particularly where using the colour adjustment tools, that it really helps to remember the complementary colours.
  • Why is the sky Blue (actually more like Cyan)?
  • Why is the Sun Red at sunset?
  • The short version is that the Sun's light (White, more or less) is scattered by molecules in our atmosphere. This scattering affects only Blue light which comes at us from all directions from all these molecules, so the whole sky looks Blue.
  • At sunset, we see the Sun through much more atmosphere than we do at mid-day. The Blue (Cyan) light is scattered so much that it is subtracted from the White light that we see, leaving Red. Red and Cyan are complementary colours!
  • The full story is here.
  • Printer Inks, CMYK and complementary colours
  • Printer inks subtract colours from the light (hopefully White light) that falls on them. What we see is the remainder of the light that is reflected back.
  • Cyan ink absorbs (subtracts) its complementary colour, Red, reflecting Cyan.
  • Yellow ink absorbs (subtracts) its complementary colour, Blue, reflecting Yellow.
  • Magenta ink absorbs (subtracts) its complementary colour, Green, reflecting Magenta.
  • Mixtures of ink produce darker colours, for example Cyan and Yellow ink mixed together reflect Green (i.e. what is left after taking out Red and Blue).
  • In theory, Black can be produced by mixing all three inks. However because of ink impurities, some amount of Black ink also has to be used.
  • More >>

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Creating a Selection using Color Range

  • Short Version
  • The Color Range tool is, in some ways, a better version of the Magic Wand. It selects areas based on various attributes of colour.
  • It can typically be used as the second of three consecutive steps:
    1. Make a rough selection around the region of interest, using the Lasso tool. This simply limits the scope of what comes next. See my section on Selections.
    2. Make the "real" Selection using the Color Range tool. This will be confined to, and will replace, the Selection of step 1. The Color Range tool is described in this section.
    3. Create a Hue/Saturation Adjustment Layer, in order to adjust the colours in the area selected in step 2. As with all Adjustment Layers, creating one will also set up the new Layer's Mask to correspond to the existing Selection (the one set up in step 2). This Mask can be "fixed" with a paint brush to make it more exact, as described here. Adjusting Hue/Saturation is described in the next section.

  • Note...
  • Color Range does not actually create a Selection until you exit the tool.
  • Up until that point, you are selecting a range of colours that will finally become a Selection. When you use the tool you only get a preview of what the Selection will look like.

select color range The tool is invoked by Select > Color Range, which produces this dialog box.

Using the top pick list , you can choose to select using an eyedropper, as shown here, or you can select areas with particular preset colours, or you can select Shadows, Midtones or Highlights.

Using the radio buttons, you choose whether the preview thumbnail shows either the image, or the selection in one of various formats (mouse-over to see a grey-scale thumbnail).

Using the bottom pick list, you can choose to see the current selection marked in a variety of ways on the image that you are working with.

select color range Grey-scale is one of my personal preferences, as shown here. It shows you the new selection as a Mask. It also shows any Selection that was in force before you invoked this tool (in this case, my rough Lasso Selection).

Mouse-over the image to see an alternative form of Selection Preview, this one using a Quick Mask representation. This overlays the area that is not selected with a (usually transparent) colour.

Picture of Quick Mask buttons If you want to use this option, then before you enter Color Range, you probably need to set up the overlay colour in order to make the overlay really stand out. You do that by double-clicking the right-hand Quick Mask button near the bottom of the Tools Palette, as described here.

Picture of Quick Mask buttons When you have set the new overlay colour, turn Quick Mask mode off by clicking the left-hand button.

eyedroppers If the top pick list shows "Sampled Colors", then you select colours using the eyedroppers.

The left-hand eyedropper selects all colours that nearly match the colour where you click. What "nearly" means is determined by the Fuzziness slider (see below).

The other two eyedroppers add to or subtract from the current selection. As an alternative to using these, you can use the Shift or Alt keys with the first eyedropper, as described in my section on Selections.

The Fuzziness slider has nearly the same effect as Tolerance on the Magic Wand. An important difference is that (unlike Tolerance) you can move the Fuzziness slider at any time while you are working with Color Range and it will change the range of colours already selected.

Load and save buttons The Load and Save buttons are very useful - and may confuse you.

When you have selected a range of colours that produces something that looks nearly right, it can be a good idea to save them (remember that you are not saving a Selection here, just the range of colours that will produce that Selection when you exit the tool).

One reason for doing this is that after you exit the tool, you may examine the Selection and find that it isn't quite right. You could, of course, just modify the Selection in the usual ways, e.g. using the Shift or Alt key with the Magic Wand tool to add or subtract from the Selection (with a low Tolerance and making sure that the Contiguous box is checked).

However, you might want to expand the view of the problem area, deselect the Selection, and then go back into the Color Range tool. In order to start from where you left off, you will need to Load the saved range of colours.

  • Note...
  • Another (and more usual) reason to save the range of colours is so that you can re-load them when you use a different tool, Replace Color. I don't use that tool, at least for now, because its functionality overlaps with both Color Range and Adjust Hue/Saturation, without being as good as either.

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Adjusting Hue/Saturation

hue / saturation dialog box I use this tool routinely in a very simple way, as one of the final steps in improving an image, to increase the saturation of all the colours by a small amount, as shown here (but there's a lot more you can do with it).

For reasons that should be familiar by now, I do this via an Adjustment Layer, so I bring up this dialog using Layer > New Adjustment Layer > Hue/Saturation.

Doing this on the Master (chosen via the Edit pick box) will affect all of the image, unless a Selection is in force when the dialog box is activated. Such a Selection might have been set up previously using Color Range, as explained above, or by some other means.

hue / saturation dialog box If you choose one of the colours in the Edit pick list, for example Yellow, you get some other ways in which to select the range of colours that the tool will work on.

The first way is via the eyedroppers, which work very similarly to those in Color Range. The difference is that there is no "Fuzziness slider" - instead, you get adjustment slider bars.

slider bars The triangles mark the edges of the range. The central dark area, bounded by two sliders, is the colour range that is "fully selected". The lighter spaces between the triangles and the two sliders is the "fall-off area", where changes will have progressively less effect.

If you use the eyedroppers then you will see all of these things move. Alternatively you can drag any of the things mentioned (the light and dark spaces, the triangles, the sliders) and they will change the selected colour range in different ways. For example, if you drag the central dark area, it will move the entire set of triangles etc. up or down the hue scale. If you experiment, it will soon be obvious what is happening.

hue saturation with colorize ticked If you tick the colorize box, the tool does something quite different. The image is converted to the hue of the current foreground colour, if the foreground color is not black or white. The lightness value of each pixel does not change.

Now if you move the Hue, Saturation and Lightness sliders, you can change any of these to what you want.

flower at different settings With the settings shown above, this is what you might end up with (mouse-over to see my original picture).

This, by the way, is the technique used to add a monochrome tint to a black and white picture. In that case, you first have to convert grey-scale to RGB (Image > Mode > RGB), and you would probably use a lower saturation.

Now, you will remember that I used an Adjustment Layer to adjust Hue and Saturation.

This allows me to do at least two neat things:

  1. flower half opacity I can adjust the opacity of the Layer, in order to dial back the effect. In this case I am going to reduce the opacity of the layer to 50%.

    I am now seeing a 50-50 mixture of the colorized version and the original version.

  2. flower at different settings I can also change the Blend Mode of the layer (Blend Modes are described in the next section). In this case I am going to choose the relatively subtle Soft Light Blend Mode.

    I am now seeing the "watered down" colorized version of step 1. blended with the original version in a particular way (mouse-over to see my original picture).

Have I got the best effect that I can yet? Probably not, but that's the beauty of Adjustment Layers. I can go back at any time and make any changes that I want.

  • Notes...
    1. The up and down arrow keys are very useful for adjusting numbers like opacity - much easier than using sliders. Use the Shift key as well to change the number by 10 instead of by 1.
    2. The eye symbol on the Adjustment Layer can be turned on and off to compare the effects with and without the adjustment (the same effect as you get when mouse-overing the above image).
    3. As a more powerful and flexible alternative to Adjust Hue/Saturation, you can use Adjust Curves instead.

The Blend Modes (as used with layers and Masks)

Introduction to the Blend Modes

Picture of canal with blends applied The Blend Modes are really useful, if sometimes confusing, especially when working with layers.

The top layer is called the blend source, each pixel of which has its own blend colour. The lower layer supplies what is called the base image, each pixel of which has its own base colour.

(Note: The Blend Modes can also be used as an option when applying paint to a base image with a Paint tool, in which case the paint tool supplies the blend colour - but that's not what I am describing in this section.)

Normally, a new layer hides the layer beneath it - that's the "normal" blend mode, which is really "no blend" in the case of Photoshop layers.

We can use a Mask to make part of a layer transparent, or semi-transparent, in which case we get a kind of blending of the layers - but that is something different from (but can usefully be used in addition to) a blend mode.

Similarly we can alter the opacity of an entire layer (which defaults to 100%), using the slider bar on the Layers palette. This also gives a kind of blending of the layers - but as with Masks, this is something different from (but can usefully be used in addition to) a blend mode.

Blend Modes can be used between two identical layers (an image and its copy in a new layer), or between layers with different images, or between a layer of colour(s) and a layer with an image (often with a Mask of varying transparency).

Blend Modes can be used (among many other things) to achieve the effect of two slides being held up to the light, taking the darker values from either image (Multiply blend mode), or two images being projected on the same screen, taking the brighter values from either image (Screen blend mode).

  • Note...
  • Photoshop also provides Blend Modes when working directly on the original image using a Paint tool - but where you can, use Layers and the appropriate Blend Modes instead.
  • The most useful of these additional non-Layer Blend Modes (at my present stage of using Photoshop) is Behind, which is one way of applying a shadow to an object (which in this case, must be surrounded by transparency).

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Dodging and Burning with Blend Modes and Layers

Dodging (lightening) and burning (darkening), as with most image adjustments, is best done using layers; see my notes below on:

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Filling with 50% grey

In using some of the Blend Modes, you may often want to fill an area with 50% grey as a starting point. Some useful ways to do this are described here.

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Blend Mode tutorials

Gold Award symbol For some really good information on the Blend Modes and what you can use them for, see this Tutorial from About.com (don't miss the introduction).

There is another useful tutorial here, with lots more links on this subject to be found here.

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Introduction to the Table of Blend Modes

Throughout the table that follows, I am using the same two Layers that will be blended in various ways. These Layers have been carefully chosen so as to demonstrate as many features of each Blend as possible.

Top layer The Top Layer shows the top half of my flower picture, with the bottom half of the flower picture replaced by transparency.

Painted onto this Layer are a number of strips of colour, which replace any pixels of the original flower image. The first strip consists of opaque white and opaque Black.

The next three strips each have a number of colours, starting with grey. The first of these strips has colours that are 75% bright, the next strip has colours that are 50% bright, and the third strip has colours that are 25% bright.

The final strip, unlike the others, is of varying transparency (created using the Gradient tool). At the left it is 100% opaque, and at the right it is 100% transparent. The colour itself is 75% bright.

Bottom layer The Bottom Layer shows the same flower picture overlaid with vertical strips of colour. These strips replace the pixels of the original picture.

The first strip is Black. The remaining strips are colours that are 25% bright, 50% bright, and 75% bright respectively.

When the two Layers are blended, the upper part of the resulting image will show what happens when an image (in this case part of the flower and its green background) is blended with itself.

This won't happen in the lower part of the image because the Top Layer consists only of transparency and colour strips in that part.

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Table of Blend Modes

BLEND MODES (MAJOR GROUPS FOR LAYERS)
Blend Mode Effect Examples of Usage
(and click link in first column)
Normal The Normal blend mode means "No Blend", which in this case means that the normal rules for viewing the combined effect of Layers apply. Normal This image, like all the similar images that follow, will only make sense if you study the two different images that are being overlaid, which are shown above.

It may be useful to remember that the vertical strips of colour belong to the lower Layer.
Dissolve The result is a mix of pixels from the blend and base colours. Each pixel in the result is either a pixel from the blend colour or a pixel from the base colour, chosen on a pseudo-random basis influenced by the opacity of the blend colour. At 100% opacity only the blend source will be visible.

For a good alternative to using this Blend Mode, see Note 1 below.
Dissolve For examples of using this mode between layers, see here, and also see Note 2 below

The White Neutral Blend Modes:
(Note: these modes all have a darkening effect)
Darken
A more accurate name for this mode would be Choose Darker.

For each pixel, all three Brightness Factors (one for each Colour Channel) of the blend colour are compared with the corresponding Brightness Factors of the base colour. The result has the lower (darker) of the corresponding pair of Brightness Factors in each case.

This obviously does nothing if the blend colour is white (hence this is a "White Neutral Blend Mode").

This mode can also be used with the Calculations Command to combine separate Masks for two objects into one Mask - see [P7A] Chap 31.
Darken Click the image above in order to see the two layers from which it was constructed.

For examples of using this mode between layers, see here, and also see Note 2 below.
 
Multiply Provides the effect of placing two image transparencies on top of each other, holding them up to a light and looking through them.

For each pixel, the Brightness Factors of the blend colour are multiplied by the Brightness Factors of the base colour to give the Brightness Factors of the result. If the blend colour is 100% white then its Brightness Factors will all be equal to 1, and multiplying by 1 doesn't change anything. If the Brightness Factors of (say) the red components of each of the blend colour and the base colour are 0.5, the the resulting red component has a brightness factor of 0.5 x 0.5 = 0.25 (or ½ x ½ = ¼). You can see that as the brightness of the two input colours becomes less and less, the result becomes darker by a greater and greater amount.
Multiply This mode has many uses. I use it temporarily when wanting to view two overlaid images simultaneously, if I am aligning them before combining them in some way, as described here.

I also use it to set up a Graduated Neutral Density Filter (as described later in this Guide).

For more on this Blend Mode, see here, and also see Note 2 below.
 
Color Burn As with the previous Blend Modes in this section, this Blend Mode actually works on each Colour Channel individually.

When the blend colour is white, this mode does nothing (any white pixels in the blend source will effectively be transparent).

As the blend colour becomes darker, this mode progressively darkens and adds contrast and more of the blend colour to the base colour.
Color burn I have used this to adjust the warmth of light in certain parts of a picture.

You can use the blend layer's Mask to isolate where the effect is to be applied. In this case I fill the blend layer with White (which is the neutral colour), and use the Paint Brush tool on the layer to progressively build up colour.

Alternatively, you can fill the blend layer with the colour to be applied, fill the layer's Mask initially with black, and use the Paint Brush tool with white at a low opacity setting to gradually lighten the Mask, which progressively introduces more of the blend layer's colour into the resulting image.

For more on this Blend Mode, see here, and also see Note 2 below.
 
Linear Burn Similar to Color Burn, but without adjusting contrast.

Unlike Color Burn, a Linear Burn with black will completely blacken the result.

As with the previous Blend Modes in this section, this Blend Mode actually works on each Colour Channel individually.
Linear Burn I haven't found a use for this mode yet (but that may change).

For more on this Blend Mode, see here, and also see Note 2 below.
 

The Black Neutral Blend Modes:
(Note: these modes all have a lightening effect)
Lighten A more accurate name for this mode would be Choose Lighter.

As you would expect, this is the opposite of Darken.

For each pixel, all three Brightness Factors (one for each Colour Channel) of the blend colour are compared with the corresponding Brightness Factors of the base colour. The result has the higher (brighter) of the corresponding pair of Brightness Factors in each case.
Lighten Andy Heatwole uses this mode to easily overlay a bright image on a dark background (the Moon) on top of the sky in a separate night-time image, where the sky in that image is lighter than the dark background of the Moon (see his video of this exercise).

P7A suggests that this mode is useful in creating Masks.

For more on the Lighten Blend Mode, see here, and also see Note 2 below.
 
Screen Provides the effect of projecting two images on top of each other on a screen, which tends to emphasize the brighter areas of both picturers. It is the opposite of the Multiply mode.

For each pixel, the Darkness Factors of the blend colour are multiplied by the Darkness Factors of the base colour to give the Darkness Factors of the result. If the blend colour is 100% black then its Darkness Factors will all be equal to 1, and multiplying by 1 doesn't change anything. If the Darkness Factors of (say) the red components of each of the blend colour and the base colour are 0.5, the the resulting red component has a darkness factor of 0.5 x 0.5 = 0.25 (or ½ x ½ = ¼). You can see that as the darkness of the two input colours becomes less and less, the result becomes brighter by a greater and greater amount.
I haven't used this mode in anger yet, although it obviously has applications in combining images for special effects.

For more on this Blend Mode, see here, and also see Note 2 below.
 
Color Dodge This is the opposite of Color Burn.

As with the previous Blend Modes in this section, this Blend Mode actually works on each Colour Channel individually.

When the blend colour is black, this mode does nothing (any black pixels in the blend source will effectively be transparent).

As the blend colour becomes brighter, this mode progressively lightens and reduces contrast while adding more of the blend colour to the base colour.
Color Dodge I haven't found a use for this mode yet.

For more on this Blend Mode, see here, and also see Note 2 below.
 

Note that there is an error on the linked page: the note at the end should read:
The Color Dodge blend mode can be used to make tonal and color adjustments to a photo as well as creating special effects like glows and metallic effects.
Linear Dodge This is the opposite of Linear Burn.

When the blend colour is black, this mode does nothing (any black pixels in the blend source will effectively be transparent).

As the blend colour becomes brighter, this mode progressively lightens and adds more of the blend colour to the base colour.

As with the previous Blend Modes in this section, this Blend Mode actually works on each Colour Channel individually.
Linear Dodge I haven't found a use for this mode yet (but that may change).

For more on this Blend Mode, see here, and also see Note 2 below.
 

The 50% Grey Neutral Blend Modes:
(Note: these modes have either a lightening or darkening effect, depending on whether the blend colour has more or less brightness than 50% grey)
(Note: in using this modes, you may often want to fill an area with 50% grey as a starting point. Some useful ways to do this are described here.)
Overlay Screens or multiplies the colors, depending on the blend colour.

Patterns or colours overlay the existing pixels while preserving the highlights and shadows of the base colour.

A blend colour of 50% grey does nothing (any pixels of this colour in the blend source will effectively be transparent).

The base color is not replaced but is mixed with the blend colour to reflect the lightness or darkness of the original colour.
Overlay This has a more contrasty effect than Soft Light (below), but is not as radical as Hard Light (below).

For more on this Blend Mode, see here, and also see Note 2 below.
 
Soft Light Lightens or darkens the colours, depending on the blend colour. The effect is similar to shining a diffused spotlight on the image.

A blend colour of 50% grey does nothing (any pixels of this colour in the blend source will effectively be transparent).

As the Brightness Factors of the blend colour (light source) move away from 50%, this mode will progressively lighten or darken the base colour, depending on whether the Brightness Factors of the blend colour are above or below 50%.

The effect is comparatively subtle. For example, a blend colour of pure white or pure black does not make the result totally white or totally black.
Soft Light Adding a 50% grey layer above an original image, and using Soft Light to blend, is better than using the Dodge and Burn Tools. Painting on the grey blend layer with a soft paint brush or air brush charged with white or black at a low opacity setting, and/or using the Gradient tool to produce shadings of grey in different arrangments, allows a wide range of subtle effects.

The advantage of using layers like this is you can switch the layer on and off to see the effect, and you can return to the layer at any time to change what you have already done.

For more on this Blend Mode, see here, and also see Note 2 below.
 
Hard Light Screens or multiplies the colors, depending on the blend colour. The effect is similar to shining a harsh spotlight on the image.

A blend colour of 50% grey does nothing (any pixels of this colour in the blend source will effectively be transparent).

Where the Brightness Factors of the blend colour (light source) are greater than 50%, the image is lightened, as if it were screened. This is useful for adding highlights to an image.

Where the Brightness Factors of the blend colour are less than 50%, the image is darkened, as if it were multiplied. This is useful for adding shadows to an image. Painting with pure black or white results in pure black or white.
Hard light In my few experiments with this Blend Mode, I have found that the opacity slider almost always needs to be dialed back, often down to 50%.

There is an interesting example of using this Blend Mode to create a dreamy effect here.

For more on this Blend Mode, see here, and also see Note 2 below.
 
Vivid Light Burns or Dodges the colours by increasing or decreasing the contrast, depending on the blend colour.

A blend colour of 50% grey does nothing (any pixels of this colour in the blend source will effectively be transparent).

Where the blend colour (light source) is lighter than 50% grey, the image is lightened by decreasing the contrast (the effect is like Colour Dodge, but not as radical).

Where the blend color is darker than 50% grey, the image is darkened by increasing the contrast (the effect is like a Colour Burn, but not so radical).
Vivid Light For more on this Blend Mode, see here, and also see Note 2 below.
 
Linear Light This is like a combination of a Linear Dodge when the blend colour is lighter than 50% grey, and a Linear Burn when the blend colour is darker than 50% grey.

It is similar to Vivid Light, but without adjusting contrast.

A blend colour of 50% grey does nothing (any pixels of this colour in the blend source will effectively be transparent).
Linear Light For more on this Blend Mode, see here, and also see Note 2 below.
 
Pin Light This is like a combination of a Lighten when the blend colour is lighter than 50% grey, and a Darken when the blend colour is darker than 50% grey.

A blend colour of 50% grey does nothing (any pixels of this colour in the blend source will effectively be transparent).
Pin Light For more on this Blend Mode, see here, and also see Note 2 below.
 

The Other Blend Modes For Layers:
Difference and Exclusion:
These specialist modes might be described here in a future update to this guide. The difference mode can be used for creating Masks of an object, if two images of the same scene are taken using a tripod, one with and one without the object in the foreground.
Hue, Saturation, Colour and Luminosity:
(Note: these use one of these attributes from the blend source to replace the same attribute in the base image.)
Hue The hue comes from the blend source, the other attributes (saturation and intensity) come from the base image. Hue For more on this Blend Mode, see here, and also see Note 2 below.
 
Saturation The saturation comes from the blend source, the other attributes (hues and details) come from the base image. Saturation For more on this Blend Mode, see here, and also see Note 2 below.
 
Color The colour (i.e. hue and saturation) comes from the blend source, with the details (luminosity) coming from the base image. Color For more on this Blend Mode, see here, and also see Note 2 below.
 
Luminosity The details (luminosity) come from the blend source, the other attributes (hue and saturation) come from the base image. Luminosity From my limited experiments so far with this group of Blend Modes, this is the one that can produce the most interesting results.

For more on this Blend Mode, see here, and also see Note 2 below.
 
 

Back to Local Contents

Notes on the Table of Blend Modes

1. Alternative to Dissolve Blend Mode
[P7A] suggests that a better effect can be obtained using Normal blend. Make a white Layer Mask and then use Filter to add Gaussian noise to the Layer Mask, and maybe also then use Gaussian blur on the Layer Mask. As usual, wherever the Mask is black, the result will be a pixel from the lower layer, where it is white then the result will be a pixel from the upper layer, and where it is grey the result will be a blended pixel. The Mask pattern can be infinitely varied using Levels, Curves, another Filter, or anything else that works.
2. Examples linked to from the Blend Table
When following links to other examples from the above table, it's useful to know that the layers that produced the results shown in those examples can be found here. The colour swatches in the top layer each fade from a starting colour to transparency. For comparison, the normal Blend Mode (no blend) with these swatches looks like this.
3. Brightness Factors, Darkness Factors and the Multiply and Screen Blend Modes
  • Short Version
  • The Brightness Factors of a colour are a measure of how bright each colour channel is (i.e. how bright are the Red, Green and Blue components of the colour).
  • The Darkness Factors of a colour are the inverse of the Brightness Factors. They are a measure of how dark each colour channel is.
  • Both kinds of factors are represented as fractional values on a scale from 0 to 1.
RGB colour values (with 8 bits per colour) range from Black (0,0,0) to White (255, 255, 255).
Bright red, for example, is coded as (255, 0, 0).
It may help to understand the mathematics of the Multiply and Screen Blend Modes, and what is actually going on in many of the other Blend Modes, if I invent a couple of new terms, Brightness Factors and Darkness Factors:
The Brightness Factors of a colour (not the same thing as the colour's Brightness, see below) are what you would get if you divided each colour value by 255, producing a fraction from 0 to 1. The Brightness Factors of Black are (0, 0, 0), for White they are (1, 1, 1), for mid-grey they are (0.5, 0.5, 0.5), and for bright red they are (1, 0, 0).
  • 50% bright grid The Brightness of the colour, expressed as a fraction from 0 to 1, is actually the arithmetic mean (a simple average) of the three Brightness Factors (more >>).
  • All of the colours on the right have a Brightness of 50%. The first square is mid-grey whose Brightness Factors are (0.5, 0.5, 0.5). However, the colour next to it has Brightness Factors of (0.75, 0.75, 0), so that two of its colour components (red and green) are more than 50% bright.
The Darkness Factors of a colour are the inverse of the Brightness Factors, as you might expect. They range from White (0, 0, 0) to Black (1, 1, 1), with mid-grey still being (0.5, 0,5, 0,5) and bright red being (0, 1, 1). They are what you would get if you subtracted each colour value from 255 (invert the colour), and then divided by 255.
If you prefer, you can think of 0.5 as ½ or 50%. It doesn't change the maths.
To turn a brightness factor into an 8-bit colour value for RGB, the program multiplies by 255.
To turn a darkness factor into an 8-bit colour value for RGB, the program multiplies by 255, then subtracts the result from 255.
I use these terms in the above table. They make my descriptions of the Multiply and Screen modes different from, and maybe easier to understand than, the usual descriptions that you will read elsewhere. Rest assured, though, that they are just another way of describing the same operations.

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