  Paradoxically, imaging with resolution much below the wavelength $\lambda$ -
now common place in the visible spectrum - remains challenging at lower
frequencies, where arguably it is needed most due to the large wavelengths
used. Techniques to break the diffraction limit in microscopy have led to many
breakthroughs across sciences, but remain largely confined to the optical
spectrum, where near-field coupled fluorophores operate. At lower frequencies,
exponentially decaying evanescent waves must be measured directly, requiring a
tip or antenna to be brought into very close vicinity to the object. This is
often difficult, and can be problematic as the probe can perturb the near-field
distribution itself. Here we show the information encoded in evanescent waves
can be probed further than previously thought possible, and a truthful image of
the near-field reconstructed through selective amplification of evanescent
waves - akin to a virtual superlens reversing the evanescent decay. We quantify
the trade-off between noise and measurement distance, and experimentally
demonstrate reconstruction of complex images with subwavelength features, down
to a resolution of $\lambda/7$ and amplitude signal-to-noise ratios below 25dB
between 0.18-1.5THz. Our procedure can be implemented with any near field probe
far from the reactive near field region, greatly relaxes experimental
requirements for subwavelength imaging in particular at sub-optical
frequencies, and opens the door to non-perturbing near-field scanning.
