Let's talk about lilac colors.  The most important thing to remember is that the color is whatever YOU see! There are a number of factors that impact the flower display.  These include the weather at bloom time - amount of sun, temperature.  The type of soil you have also affects the color.  The bud color is not always the same as the color of the opened florets.  There are 7 basic color groupings that are assigned to lilac varieties, but the variations of hue and value are very nuanced.  I've grouped my lilacs into these categories and added an 8th category for unique varieties that don't quite fit into one of the 7.  But keep in mind that what you see as magenta, someone else may see as purple!