Revised 03/25/2020
11
7.)
Beam Tilt Pivot Points
a.)
Focus
(RC “Focus”) the specimen to
minimum contrast
.
Note: the “Focus” knob has two parts. The smaller,
inner knob changes the focus. The larger, outer knob
adjusts th
e “Focus step” i.e., how much the focus
changes with each movement of the inner knob.
b.) Move to a
non-beam-sensitive area
of the
sample.
Converge
(LC “Intensity”) the beam to
crossover and
center
it (LC trackball).
c.)
Select “
Beam tilt pp X
” from “Direct Alignments”.
d.) Use the
MF knobs
to
superimpose
the two
beam
spots
and minimize the beam movement.
e.)
Press “
Done
” in “Direct Alignments”.
f.) Repeat steps b
–e for “
Beam tilt pp Y
”.
8.)
Beam Shift
a.)
Converge
the beam to crossover (LC “Intensity”) and
center
it using the
LC
trackball
.
b.)
Select “
Beam shift
” from “Direct Alignments” and use the
MF knobs
to re-
center the beam on the screen.
c.)
Press “
Done
” in “Direct Alignments”.
9.)
Rotation Centering
Note: Rotation centering is the most important alignment for high-resolution work
on this microscope. It should be done carefully and at or above the magnification
that will be used for imaging.
a.) Find a suitable area of the specimen and
focus (
RC “Focus”)
to minimum
contrast
at a magnification (RC “Magnification”)
above 100kx
.
b.)
Select “
Rotation center
” from “Direct Alignments”. Use the
MF knobs
to
minimize image movement
. The center of the image should pulse in and out
Focus
Focus step
