  Transient-field $g$-factor measurements in inverse kinematics were performed
for the first-excited states of the stable, even isotopes of Ge and Se. The $g$
factors of $^{74}$Ge and $^{74}$Se were measured simultaneously using a
cocktail beam, which eliminates most possible sources of systematic error in a
relative $g$-factor measurement. The results are $g(^{74}{\rm Se})/g(^{74}{\rm
Ge})=1.34(7)$, $g(^{70}{\rm Ge})/g(^{74}{\rm Ge}) = 1.16(15)$, $g(^{72}{\rm
Ge})/g(^{74}{\rm Ge})=0.92(13)$, $g(^{76}{\rm Ge})/g(^{74}{\rm Ge})=0.88(5)$,
$g(^{76}{\rm Se})/g(^{74}{\rm Se})=0.96(7)$, $g(^{78}{\rm Se})/g(^{74}{\rm
Se})=0.82(5)$, $g(^{80}{\rm Se})/g(^{74}{\rm Se})=0.99(7)$ and $g(^{82}{\rm
Se})/g(^{74}{\rm Se})=1.19(6)$. The measured $g$-factor ratios are in agreement
with ratios from previous measurements, despite considerable variation in
previous reported absolute values. The absolute values of the $g$ factors
remain uncertain, however the Rutgers parametrization was used to set the
transient-field strength and then compare the experimental $g$ factors with
shell-model calculations based on the JUN45 and jj44b interactions. Modest
agreement was found between experiment and theory for both interactions. The
shell model calculations indicate that the $g(2^+_1)$ values and trends are
determined largely by the balance of the spin carried by orbital motion of the
protons.
