Advanced photographic editing in Photoshop

Blending Modes calculate two image sources together to create new values.  In order to use Blending Modes there must first be two sources, such as layers, brushes, fills or Adjustment Layers.  There are currently 27 different modes in Layers.  Of these, only 11 are of real use in photography.

In the following examples the top layer is blended with the bottom layer to create the new result.

TONAL BLENDING MODES

Normal: Tones are overlaid without pixel replacements.  Used to combine pixel values with changes in Opacity.  Set by default.

Darken: Darker pixels replace overlapped lighter pixels.

Multiply: Intensifies the image.  Overlapped pixel values are multiplied, then divided by the maximum dark pixel value in the image.  Good for intensification of local image areas.

Lighten: Lighter pixels replace overlapped pixels that are darker.  Opposite to Darken.

Screen: Overlapped pixel values are added together, then divided by the maximum dark pixel value in the image.  Good for reducing (opening) shadow areas.  Opposite to Multiply.

Overlay: Combination of Multiply and Screen.  Dark areas are multiplied and light areas are screened.  Areas of 50% grey produce no change.  Used to ‘dodge’ and ‘burn’ on a layer.

Softlight: Less intense version of Overlay.  50% grey produces no change.

COLOUR BLENDING MODES

Hue: Combines the colour (hue) of the active layer, with the saturation and brightness of the underlying layer.

Saturation: Combines the saturation of the active layer, with the brightness of the underlying layer.

Colour: Combines the hue and saturation of the active layer, with the brightness of the underlying layer.

Luminosity: Combines the brightness of the active layer, with the hue and saturation of the underlying layer.

1. Create a new layer directly over an image layer.
2. Choose Edit > Fill… and select 50% grey.
3. Set the Blending Mode of this fill layer to Overlay.
4. With the Brush Tool, paint with a tone that is brighter than 50% grey to ‘dodge’ in the image, and darker than 50% grey to ‘burn’ in the image

Extract a colour channel from the image, make a new layer from this channel, blend this layer on Luminosity.

Use the following as a guide for determining the appropriate channel

+1 Intensification use the Red channel | +2 Intensification use the Green channel | +3 Intensification use the Blue channel.

1. Add a new blank layer above the image layer, make sure this is the active layer.

2. Extract the colour channel using the Image > Apply Image… command, select one of the channels

3. The new layer should now contain the tones from the channel selected in step 2 (in the above screen shot this is the Green channel.  Blend this layer on Luminosity.

Create an image layer that opens shadows and intensifies highlights.  Great for landscape images.

1. Duplicate the image layer

2. Choose Image > Adjustments > Desaturate to make the new layer a tone layer only

3. Choose Filter > Blur > Gaussian Blur… Set the Amount to 250 pixels

4. Choose Image > Adjustments > Invert to make the light areas dark and the dark areas light.

5. Set the Blending Mode to Overlay.

This is a quick way to add dynamic tonal variation to an image.

1. Add a Black and White Adjustment Layer

2. Set the Blending Mode to Luminosity.

3. Change the Black and White layer Preset to one that achieves the desired result.  For example, setting the preset to Green Filter will lighten strong colours or enhance green foliage against a sky.

Use this method to isolate shadow values in an image and reduce their intensity (open them up).  To do this we need to use the Calculations command to combine multiple channels together to make a new channel.

1. Choose Image > Calculations… and apply the following settings;

Source 1:
Set the Layer to Background, set the Channel to Grey, tick invert.

Source 2:
Set the Layer to Background, set the Channel to Grey, tick invert.

Set the Blending to Linear Burn, set the Opacity to 100% (reducing Opacity will increase the smoothness of the Mask).

Set the result to New Channel.  You will now have an additional Channel in the Channels Panel where the shadow areas are white, and the midtones and highlight areas are black.  This is the Shadow Mask.

2. From the Selection Menu, Choose Select > Load Selection… and choose the Channel created in Step 1.

3. Add a Curve Adjustment Layer and set the Blending Mode to Screen.