original: Thirdly, for some color blind people, color can only be distinguished if there is a sufficient "mass" of color: thin lines might appear black while a thicker line of the same color can be perceived as having color.
simplifications: For some color blind people, color can only be distinguished if there is a sufficient "mass" of color.  That means thin lines might appear black while a thicker line of the same color can be perceived as having color. For some color blind people color can only be seen if the lines are thick enough. If a colored line is too thin it may look black to them. Thirdly, for people who can't see color, it can only be seen if it is concentrated enough. Thin lines might appear black while a thicker line of the same color can be perceived as having color. Some color blind people can only see a hue if there is a sufficient area of color. Thin lines might appear black. Thirdly, for some color blind people, color can only be told apart if there is a enough "mass" of color. Thin lines might look black. Meanwhile, thicker line of the same color can be seen as having color. Thirdly, for some color blind people, color can only be seen if there is a enough "mass" of color. Thin lines might appear black while a thicker line of the same color can be seen with color. For some color blinded people, color can only be distinguished if there is a sufficient "mass" of color. Thin lines might appear black while a thicker line of the same color may be perceived as having color. Some color blind people can see color if there is enough "mass." For example, thin lines might look black but thicker lines will look like the color they are. For some color blind people, they can only recognize color if there is enough of a thickness of that particular color. Third, some color blind people can only see color if there is enough "mass" of color.  Thin lines seem black, but thick lines can be seen in color.