Trigonometry Vs 3dsmax Rotation mismatch?

[kalpal]

Hi all,
so I am trying to rotate a plane in order to cancel its rotation value on the X axis, and to figure out the angle of rotation needed, i tried to apply a trigonometric principle of arcSin, but i noticed something weird which is:
In a triangle where
X is the front line and = 250
Y is the adjacent line and = 500
the angle Value should be : Asin(x/y) and in this case is 30 degrees…

but in 3dsmax the rotation of the face is 26.5651 for some reason, any idea what i am doing wrong? or explanation?!

question|690x388

[Srek]

You might like to ask this in the max subforum.
In general 3D applications seldomly use trigonometric operations to caluclate rotations, they either use matrix or quaternion transformations, both of which can lead to different results, especially when multiple rotations are done in an unspecified order.

[kalpal]