A non-uniform appearance of color that occurs when a wall is painted with a roller and the edges (where the roller could not reach) are "cut in" with a brush. The brushed areas generally appear darker, thus resembling the frame of a picture. Sprayed areas may be darker than neighboring sections that are brushed or rolled.
- Applying paint at different film builds (e.g. thickness of each coating layer) as a result of using a thick brush cut-in application versus a thin roller application. Spraying versus brushing may also show the problem because of differing film builds.
- Not keeping a wet edge while painting (i.e. applying wet paint to the edge of dry or almost dry paint).
- Incomplete mixing of the paint; material that has settled to the bottom is not uniformly incorporated.
- Don't cut in the entire room before painting the larger areas. Work in smaller sections of the room to maintain a wet edge. When using a brush, only cut in as narrow an area as needed, usually 1" to 2", using the roller as close to the corner as possible.
- Apply the coating as uniformly as possible with any application method.
- All colors, including white, should be thoroughly shaken before use.