This tutorial was originally written for PAINTER 5 in response to an e-mail list question about "how to erase on a Transparent Layer". It is been revised for Painter 6 and the words  "Transparent Layer" are replaced with "Layer".  It's a tutorial about working with Layers and Layer Masks, which will explain "Erasing" in the title of this tutorial being in quotes, as the effect (in this example) of painting on the mask is removal of part of a painted line. Although, in Painter 6, there are no Transparent Layers and it's possible to erase directly on the Layer itself, this exercise will help to make the beginning Painter user familiar with both Layers and Layer Mask editing. 

General Notes:

In this tutorial you'll be working with Layers and Layer Masks. There are some general rules that cover Layers. Some of these rules are described in the following paragraphs: 

In the Layer List,  the layer's eye-icon makes the layer visible (open) or invisible (closed). The small black lock icon locks and unlocks the layer. When locked, it's  impossible to move the layer. In the Layer List, when the Layer  is highlighted, it is selected, and active. When a Layer  is selected and active (and, in the Layer List, Show Layer Marquee is checked) it has a thin black-and-yellow striped frame around it. This makes it possible to see which Layer or Layers are selected when working on a more complex image. When a Layer is selected, as well as painting on the Layer, many of the Effects menu selections may be applied to it. 

To open or close a Layer, click on its eye-icon. To lock or unlock a Layer, click on the small black lock. Click in the Layer List, on the appropriate Layer, to select and activate it (you may be working with a large number of Layers). 

For the purposes of this tutorial, the lock may remain in the unlocked position as shown next to Step 2 of the following instructions.

Masks can be confusing. It's best to remember that nothing new is created on the Mask. What is on the Mask is only a reflection of what was painted on the original, whether that original is an Image Layer made from a selected area of the Canvas (Selection) or it was created by checking New Layer in the Layers palette drop-down menu. 

A Mask is a masked area of an image.

In the old days of graphic production, masks were cut from rubylith, a film on acetate that was laid over an image on the art board then cut and peeled away and used to expose or burn away selected areas of the image and block light from other areas (to burn away a cluttered and distracting background behind a piece of machinery, for instance). Masks were also used to define areas of color (color separations, done manually). The cutting required a sharp, clean blade, a steady hand, and good eyesight. The tiniest slip and the mask was ruined as the edges had to be perfectly cut. A miniscule flaw stood out like a sore thumb on the printed piece. 

At the print shop, negatives were shot then printing plates made. Printers had, and still have, skilled workers who touch up those negatives, remove smudges and spots from what will be light printed areas of the image by painting over the dark flawed parts of the negative to block out light, for example. 

Now, we can do this kind of touch-up in Photoshop, Painter, and other applications, either on a finished image or as we create it, as part of the creation process. This is, in a way, similar to the old way -  before computers and all the wonderful software we have now and it's  much more fun.

In Painter, Masks are used a lot in the creation process as you'll see:

1. In the File menu, select New and open a new, White, canvas.
 

2.  From the Objects palette, Layers drop-down menu arrow in the upper right corner of the palette, click New Layer. (For PAINTER 5, in the Floaters palette, Floater menu, click Transparent Layer).

3.  In the Brushes palette, make the following selections:

• Brush Popup: Felt Pens (or your choice)
• Brush Variant Popup: Dirty Marker (or your choice)
• Method: Plugin (only needed for PAINTER 5)
• Subcategory: Transparent Layer Brush (only needed for PAINTER 5)

4. With Layer 1 highlighted, paint a stroke on Layer 1 (PAINTER 5, Transparent Layer).
. 5.  In the Objects palette, click Masks to open the Masks sub-palette.  (For PAINTER 5, in the Objects palette, click the Mask icon to open the Mask palette.) 6.  Notice that RGB - Layer 1 is highlighted (active) and Layer 1 Mask is not highlighted (not active) and its eye-icon is closed.  (In PAINTER 5, these are the  RGB - Transparent Layer and the Transparent Layer Mask)	.
. 7.  Click Layer 1 Mask, then click its eye-icon to open Layer 1 Mask and make it active (in PAINTER 5, Transparent Layer Mask).	. .
. 8.  Notice that RGB - Layer 1 is no longer active and your stroke is BLACK.  This is because you are now seeing the  Layer 1 Mask (PAINTER 5Transparent Layer Mask).	. .
. 9.  In the Art Materials palette, click Colors to open the Colors sub palette. (For PAINTER 5, in the Art Materials palette, click the Color icon to open the Color sub-palette.	.

10.  In the lower left corner of the Color palette, notice the two Color Swatches, the Primary Color (in front) and Secondary Color (in back). These swatches show the colors you last used (or that were the default colors when you launched PAINTER).
 

11.  In the Art Materials palette, click the Primary Color (front) swatch, then click in the Saturation/Value Triangle to make the Primary Color WHITE.
. 12.  In the Art Materials pallette, click the Secondary Color (back) swatch, then in the Saturation/Value Triangle to make the Secondary Color BLACK.	. .

NOTE:  If you should ever need to switch the Primary Color swatch color and Secondary Color swatch color from front-to-back and vice-versa, click on the small double-headed sweep-arrow next to the Primary Color and Secondary Color swatches.

• Brush Popup and Brush Variant Popup: Choose a brush that completely covers with a stroke that is not grainy, is not spotted, and does not smear the Mask.


For this exercise, you'll want to completely remove part of the painting. A brush, for instance, that picks up the paper texture, like Dry Media Gritty Charcoal, will leave grainy painted areas on Layer 1 (you'll see them in reverse on the Mask). 

Test your brush choice before doing the final mask editing.
 

• Controls Palette: Move the Opacity Slider to 100%. 


NOTE:  On a future image, to edit a Mask and create soft edges, try using Airbrush, Fine Spray. Also, the Controls Palette Opacity Slider can be moved to change opacity and achieve the desired result.

14.  On the Layer 1 Mask (Painter 5 Transparent Layer Mask), with WHITE the Primary Color, "paint" ("erase") away the top half of your stroke.  Be sure that your brush size is large enough not to leave tiny unpainted areas as you brush across the canvas. Zoom  in to check for missed areas as these  will show up as tiny paint spots or streaks when you return to Layer 1  (in Painter 5, the Transparent Layer) as well as in your final image, especially in print.
. 15.  In the Objects palette, Mask List, click the Layer 1 Mask eye icon to close the Layer 1 Mask, then click RGB - Layer 1 to highlight it and make it active.  (In Painter 5, click the Transparent  Layer Mask eye-icon to close the Transparent Layer Mask, then click  RGB - Transparent Layer to highlight it and make it active.)	.
. 16.  In the Objects palette, Layers List, click Layer 1 to highlight it and make it active.  (In Painter 5, click Transparent Layer to make it active.)	.

17.  Notice that your stroke is colored. This is because you're on Layer 1 again, not on the Layer 1 Mask. (In Painter 5, you're on the Transparent Layer again, not on the Transparent Layer Mask.)

18.  In the Brushes palette, choose a Brush and continue to paint.

(In Painter 5, add to your Brush choice:

• Method: Plugin
• Subcategory: Transparent Layer Brush)