Euler Angle transformation, help!

I'm doing a research project currently and basically what I have is a camera measuring a probe. I have designed the camera to give the orientation of the probe using euler angles in the camera's frame of reference. This was working for most of my data, but now I need a 3-D visualization of what the camera on the tip of the probe would see. In order to do that, I now need to know the euler angles in the probe's frame of reference.

I know how to make rotation transformations using euler angles for vectors, but for some reason this problem is confusing me. I need euler angles in one frame where I have the euler angles in another frame. Suggestions on how to make this work are greatly appreciated, thanks!

EDIT: An easy way would be IF I KNEW the angles between the two coordinate systems, but unfortunately one of the coordinate systems (the probe) is constantly changing. So it is a little more complex than simply adding angles and subtracting them. All I need though I guess, is a formula that gives me the instantaneous transformation. Then I can just put that into my MATLAB code and I'll have all the data I need.

DATA AVAILABLE:

- Vector between two coordinate systems
- Orientation of probe at any instance of time (but changing in time)
- Euler angles of probe in camera's reference frame
- Rotation matrix between both coordinate systems at any given instance of time