Yesterday, with Titouan, we made some measurements on pointing stability of the laser beam after amplifier and CVBG.
the amplifier beam go through a first telescope to be small enough and colimated before going to CVBG's, then go to CVBG's and then is sent through the FP-cavity telescope to the FP-cavity itself.
the total length is about 6m to mirror M1.
the surface of the mirror M1 is imaged with several wedges to a Basler CCD.
(x is for veritcal position and y is for horizontal position)

* the 1st plot shows the pointing stability at low power of amplifier without airflow and walking around during about 5 minutes extracted from the Basler CCD video.
when walking around or with airflow the pointing stabily is much worse.

* the 2nd plot shows the pointing stability vs amplifier current.
it is comparable (a litle bit worse) to the pointing stability at low power.
one clearly see the beam expanding in vertical direction and also in horizontal direction.
the effect could come from the CVBG telescope lenses which are standard lenses and not high power lenses.
the pointing effect could come also from the same effect if the lens is not perfectly centered.

we took also some picture of the CVBG at different power with the Thermal camera but we need to get the data from camera (old software not compatible with Windows 10)