  We analyze in details the properties of the conditional state recently
obtained by J. Wenger, et al. [Phys. Rev. Lett. {\bf 92}, 153601 (2004)] by
means of inconclusive photon subtraction (IPS) on a squeezed vacuum state
$S(r)\ket{0}$. The IPS process can be characterized by two parameters: the IPS
transmissivity $\tau$ and the photodetection quantum efficiency $\eta$. We
found that the conditional state approaches the squeezed Fock state
$S(r)\ket{1}$ when $\tau,\eta \to 1$, i.e., in the limit of single-photon
subtraction. For non-unit IPS transmissivity and efficiency, the conditioned
state remains close to the target state, {\em i.e.} shows a high fidelity for a
wide range of experimental parameters. The nonclassicality of the conditional
state is also investigated and a nonclassicality threshold on the IPS
parameters is derived.
