How to Paint with Multiply Blending on a Brush Instead of a Separate Layer

A brush blend mode controls how incoming paint combines with existing pixels during painting. A layer blend mode controls how a layer combines with layers beneath it. Krita explicitly supports blending per brush stroke and per layer; its layer system then composites the stack into the visible image. (Krita Basic Concepts, Introduction to Layers and Masks)

For this workflow, paint onto the layer that actually contains the colors you want to shade. A transparent layer above the character does not contain those base-color pixels, even though you can see them through it. Consequently, putting Multiply on the brush there does not substitute for setting that upper layer to Multiply. This follows from the distinction between painting into a layer and compositing separate layers.

Direct painting also commits the shading to the same pixel artwork as the base colors. Returning the brush to Normal changes subsequent strokes; it does not separate earlier shading from the underlying paint. Save a working copy before starting if you want an easy route back to the unshaded version. Krita describes paint layers as raster images whose applied effects cannot be independently edited afterward. (Krita Paint Layers)

In Photoshop desktop, use the ordinary Brush tool and select an existing raster layer containing the character’s base colors. Adobe places the brush’s Mode, Opacity, and Flow controls in the options bar. (Paint with Brush or Pencil tools in Photoshop)

1. Save a working copy of the illustration.
2. Select the painted character layer in the Layers panel and leave its layer blend mode at Normal.
3. Select the Brush tool and a simple round brush.
4. In the brush options bar, change Mode to Multiply.
5. Choose a light gray foreground color and start with 20% brush opacity as a practice setting.
6. Paint one short stroke over a colored area, release, then paint a second stroke across part of the first.
7. Undo the test strokes before shading the character.

Use an existing raster layer for this test. Adobe documents that painting on certain other layer types, including text and shape layers, can automatically create a new transparent layer, which changes where your paint lands. (Photoshop painting tools)

In Krita, select the paint layer containing the character’s colors and activate the Freehand Brush tool with B. Then use Alt + Shift + M, the documented default shortcut for the painting Multiply mode. Krita specifically states that these painting shortcuts do not change the current layer’s blend mode. (Freehand Brush Tool, Blending Modes)

Keep the layer at Normal and repeat the same two-stroke test: one stroke across the base color, followed by a separate stroke overlapping it. Use a simple pixel brush initially so texture and other preset behavior do not complicate your comparison. When you finish shading, press Alt + Shift + N to return the painting mode to Normal. These are default shortcuts; customized assignments may differ. (Krita Blending Modes)

Multiply combines corresponding color channels by multiplication. White leaves the existing color unchanged; black produces black. Intermediate colors can darken the base, and repeated strokes can darken it further. A colored Multiply brush can also change the resulting hue because its channels affect the base color by different amounts. (Adobe blending mode descriptions, Krita Arithmetic blending modes)

Start with light neutral gray when your immediate task is to understand the character’s shadow shapes. Once those shapes read clearly, test a lightly tinted shadow color on representative areas of the palette. Check both the main body color and any contrasting markings: a tint that looks useful on one can produce an unwanted shift on another.

Here is an illustrative calculation using normalized channel values, full brush opacity, and opaque base pixels. A base value of 0.80 multiplied by a brush value of 0.75 becomes 0.60. Applying the same multiplication again gives 0.45. This demonstrates why repeatedly crossing one area can make it much darker. It is a numerical illustration, rather than a prediction of exact displayed swatches under every color-space and brush setting. (Multiply arithmetic)

Use the following exercise on one broad area of your character. The suggested opacity is a starting point for practice, not a required setting.

1. Choose the light direction. For example, place the imagined light above and to the left, then identify the character surfaces facing away from it.
2. Choose one shadow shape. Start with a broad side plane rather than several tiny details.
3. Apply one controlled pass. Use a brush large enough to cover the intended area with few strokes.
4. Release and inspect. Compare the shadow with untouched base color before adding more paint.
5. Deepen a smaller region. Add a second pass only where you deliberately want stronger shading.
6. Return the brush to Normal. Use Normal painting for opaque corrections and highlights.

Treat brush opacity and flow as separate controls. Opacity governs paint transparency; flow governs how paint accumulates through brush dabs. In Krita, the brush’s Wash and Build-up painting modes further affect whether opacity behaves at stroke or dab level. If a preset accumulates darkness faster than expected, examine those settings before repeatedly reducing opacity. (Krita Opacity and Flow)

For a clean shadow boundary, choose a firmer brush edge. For a gradual transition around a rounded character form, use a softer edge and work in broader passes. Judge both at the illustration’s intended viewing size: small character details can become difficult to distinguish when too many dark passes gather around them.

Use this diagnostic sequence to isolate the cause before changing several settings at once.

What you see	What to check	Next action
Paint looks like an ordinary colored mark	Whether the selected layer contains the base colors	Select the painted layer and repeat one test stroke
White seems to do nothing	Foreground color	Choose light gray; white is neutral in Multiply
Crossings become too dark	Repeated passes and brush accumulation	Undo the extra pass, then use fewer, broader strokes
The shadow changes the palette unexpectedly	The brush color’s tint	Compare light gray with a lightly tinted alternative
Painting keeps darkening after shading is finished	The brush’s current blending mode	Switch the brush back to Normal

The white-neutral behavior and progressive darkening are documented properties of Multiply. The troubleshooting actions apply those properties to the character-painting workflow. (Adobe blending mode descriptions)

If the latest pass is too strong, undo it and repaint with a lighter brush color, lower opacity, or fewer passes. Painting white while the brush remains in Multiply will not restore the original color, because white leaves the current result unchanged. (Adobe blending mode descriptions)

For an opaque correction, switch to Normal and select the intended replacement color from an untouched area or your original palette. Avoid sampling the shaded region when you want the original base color: that sample already includes the darkening. If the correction needs the exact earlier artwork, return to the saved version.

Finish by checking the character at its intended display size. Keep the shadow shapes that clarify its form, correct any accidental overlap bands, and confirm that the brush is back in Normal mode. The useful habit is to inspect each pass before adding another; direct Multiply painting works best when every additional darkening stroke has a clear purpose.

• Adobe Photoshop: Paint with Brush or Pencil tools in Photoshop
• Adobe Photoshop: Blending mode descriptions
• Krita Manual: Blending Modes
• Krita Manual: Basic Concepts
• Krita Manual: Introduction to Layers and Masks
• Krita Manual: Paint Layers
• Krita Manual: Freehand Brush Tool
• Krita Manual: Arithmetic
• Krita Manual: Opacity and Flow