Leginon

h1. Scaling Image Shift Matrix Calibration

High magnification stage position calibration is often difficult if not impossible to perform although it plays a role in determining the orientation of the reference space for image shift targeting between mags.

Get a better estimate of stage position matrix at en magnification by scaling the matrix at hl mag.

You can find the matrix in image report (Click on the "i" in the myamiweb imageviewer toolbar)

Scale the matrix by magnification will give a reasonable value.

For example, if your hl preset at 1300x has a matrix of

<pre>

2e-9  -6e-9

-6e-9 -2e-9

</pre>

Then a good estimate of the matrix for your en preset at 22500x would be multiplied by 1300 / 22500 and becomes

<pre>

1.16e-10 -3.47e-10

-3.47e-10 -1.16e-10

</pre>

You can enter the result directly in Calibration application Matrix node using "Edit" tool at the toolbar after the required preset is sent.