# Two capacitors in parallel vs series - electric field?

If we have two parallel plate capacitors in parallel, do the electric fields between their plates have to be the same? What happens if we have a coaxial cable of length $L$, which looks like this: One part of it (length $X$) is filled with a dielectric of relative permittivity $\epsilon_r$. Are the two electric fields $E_1$ and $E_2$ between the inner and outer electrodes the same? If we look at the cable as two separate cylindrical capacitors of lengths $X$ and $L-X$, are those capacitors then connected in series or parallel in this case?

Edit: Electric field using Gauss's law (in case $X=\frac{L}{2}$).

Since the two cylindrical capacitors are in parallel, $E_1$ and $E_2$ are the same, so we know, by Gauss's law, that: $$\oint_S{DdS=Q}$$ $$\epsilon_0E2{\pi}r\frac{l}{2}+\epsilon_0\epsilon_rE2{\pi}r\frac{l}{2}=Q$$ $$\epsilon_0E(1+\epsilon_r){\pi}rl=Q$$ $$E=\frac{Q}{{\pi}rl\epsilon_0(1+\epsilon_r)}$$ I'm not entirely sure if I correctly solved the integral.