PY151

A hard-to-find bright and clear yellow with high lightfastness, this is one of many benzimidazolone yellows. Most manufacturers give this color solid 8's (highest marks) for lightfastness, with just one showing a bit of fall-off in tints. PY154 may have slightly better lightfastness than PY151. This is a fairly rare color to find as a single pigment in oils. According to this article it is used as John Deere yellow. It was recently made by Daniel Smith before they ceased to make oil paints, however, it can sometimes be found as a constituent of blends. In watercolor, Schmincke's version is a bright middle yellow which is a touch more green-leaning (while very much appearing yellow) than their version of PY154 which is very slightly warmer. Schmincke gives their version four out of five stars for lightfastness (five stars is more like the super solid earth tones), meaning very high lightfastness.