improve the precision to detect points

[henriquem]

I notice that in each image the points not is exactly in center point of nose (For Example)
corner: mouth or eyes.
It is perceived a small detour, even converting to grayscale

cvCvtColor(srcImg, grayImage, CV_BGR2GRAY);

In my case, How I could to improve for the precision, to after I could to calculate the distances of points for recognition face to be Better, and not occur risk of error ?

I'm anxious for you translate JNI JAVA the new version clandmark!!!
:-)
Contratulations about new project