Index (this will be updated as the series unfolds)
Part 1a: Importing Files and File Types
Part 1b: Camera Raw
Part 2: Colour:
Part 3a: The Workspace
Part 3b: Example Layers Workflow
Part 3c: Adjustment Layers
Part 4: Grouping, Masks & History:
Layer Groups
Masks
Positive/Negative Rule
Gradients
History
Part 5: Selection and Paths (Pen Tool)
Part 5b: Healing Brush, Patch or Clone Stamp Tool?
Part 6: Image Size & Interpolation
Layer Groups
So now you're a master of layers, you may want to figure how to keep them nicely tucked away and tidy. Grouping layers is very easy - simply click the Create a new group folder icon in the Layers window to generate an empty folder in your layers stack.
Then simply decide which layers you want to be in that group by clicking and dragging them in. Holding Ctrl and clicking many layers allows for multiple selection, which can then be dragged in to save time.
A Group can be treated in the same way as a single layer can - but any adjustments will apply to all layers within the group. In this case - ideal for grouping together - the eight different adjustment layers for image levels and colour balance:
Just for fuller housekeeping, that arrow to the left of the folder itself can be clicked to either hide or display the contents. When it's required for re-editing it can be bought up, otherwise it's best left tucked away.
Masks
We're not just talking about carnivals and those Venetian masked balls beloved by advertising agencies. By definition, a mask is 'anything that conceals or disguises' - which is exactly what Photoshop masks are designed to do (at least in part).
Applying an adjustment layer to an image is fine, but what if you wish to utilise the effects of that adjustment to only a specific area of the image (or another layer) instead of the whole image? This is where masks come into play, as they allow for the application of an assigned effect to be absolutely at your control.
Having followed this tutorial so far, you have already been applying masks in the form of adjustment layers - it's that extra white frame that appears to the side of a layer.
Here's a step-by-step example that will explain the basics of masking, detailing the processes taking place:
We have an image, but wish to change the colour of the eyes from blue to green. So generate an adjustment layer for colour correction, changing the values as appropriate.
Caption: Adjustment layer: Colour Balance: Adjusted values
Caption: Effects of Adjustment layer mask over entire image
Positive/Negative Rule (for masks)
The information attached to a mask ranges from white to black - where white is 'on/open' and black is 'off/closed'.
At the moment the mask is 'white', so the applied colour balance is affecting the entire layer. It is at your disposal to 'paint' into a mask utilising Photoshop tools. In this instance we are looking for the mask to affect a small area - the eyes - so it is best to paint the whole mask black to 'turn off' the applied colour balance.
By selecting the Paint Bucket tool (G) and making the available brush palette black and white (D) it is possible to fill the whole mask black, thus preventing any effects applied to the mask.
Caption: Now with the mask filled black, the layer is not affected by the colour balance adjustment
By selecting the Brush tool (B) and setting the brush colour to white in the palette (X) it is possible to brush into the mask, 'revealing' the adjustment layer in the desired areas. Much like making a custom filter that you could plonk in front of your cameras lens.
Caption: Now with the mask filled black, the layer is not affected by the colour balance adjustment
Zoom in for accuracy and brush as appropriate - it's possible to brush in greyscale if straight black or white is too harsh for the mask reveal. This can also be achieved by adjusting the flow/opacity/airbrush settings as appropriate.
(Note: (X) is a quick shortcut to toggle between the two selected palette colours, where (D) is a quick shortcut for black and white to become the selected colours. These should be remembered as only greyscale (black - white) affects the mask information.)
Caption: Initial brushing in
Caption: Brushing complete. Notice the white brushing appears on the mask layer to represent where the mask is active
Gradients (for masks):
It's important to note the use of black and white (greyscale), as this represents the degree of visibility from all to nothing. This becomes distinctly useful when utilising the Gradient tool (G) for example.
It is possible to set up a gradient as a smooth fade from black to white:
If you wanted to create a smooth vignette effect (darker around the corners), then it would be a mean feat by brushing alone. This is where it's best to let the computer do it for you and use the gradient tool.
Set up an adjustment layer (as before) to darken the whole image. Fill the layer black so there is no effect. Then to bring the effect of the adjustment layer to the edges, it is possible to drag the selected gradient type across the mask.
Click and drag the pointer in as far as you wish the gradient to take effect. Take note of the mask itself to visualise those areas unaffected.
History
Now seems as good a time as any to interject a bit of History. Like a classic sci-fi plot, Photoshop History allows for you to jump back in time to 'undo' an action or series of actions (however, it doesn't allow you to travel forward 80,000 years and bag off with an Eloi, or get chased by rifle-wielding gorillas on horseback). (Ctrl+Z) undoes most recent single action only.
Every time you perform an action in Photoshop it is logged in History - showing which tool was used and what action was performed. If you overwork something, make a mistake, or just want to click back and see how something looked x-number of actions previous, then simply clicking in the History will take you to that stage in time.
The content that becomes 'undone' fades to grey (as above). If you click back in History and then perform additional actions, then all undone actions will be lost. It's worth noting that PhotoShop's default History only records 20 actions, which may seem small when performing some serious edits - especially after making 21 brush strokes that you then realise don't look right, but can't go back to the stage you wish.
To adjust the number of History actions (up to a potential 1,000), go to Edit > Preferences > General (Ctrl+K). From here select the Performance tab on the left, and the History options appear to the right. Change to how many you wish to be working with, click OK, and away you go! Remember that the History file does take up memory, so if you are handling a big image file and have a huge History backlog, Photoshop will slow down significantly.
