i am loathe to post this in some ways for fear of public embarrassment at having totally misunderstood the issue here, but this thread has been confusing me. isn't this something related to what you want jirko?:
not entirely sure. the pic shows eighth-note triplet = 0.6667. so sixteenth-note triplet would be 0.3333 and so on. the triplet values will be these "thirds" kind of numbers, the duple values should be 0.5, 0.25, 0.125 etc.
Though I would have thought that a quarter-note would be 1.0, and therefore the quarter-note triplet would be 0.6667. Maybe the eighth-note is the 1.0?