Atomic detectors for sensing and measurement of AC electric fields show certain advantages over traditional dipole antenna, such as the capability to measure absolute electric field strengths, and a higher physical resolution. Here I will present experimental detection of incident RF fields, using electromagnetically induced transparency (EIT) spectroscopy on Rydberg states within an atomic vapor. The small (5.5 x 5.5 mm cross-section) Rubidium vapor cell is used to image the field the near-field from a microwave horn, to a spatial resolution of lambda/10, covering a field-amplitude range from 50 to 350 V/m. Results are compared to finite-element field simulations, and further experiments demonstrating the ability to record absolute field amplitude and frequency values will be discussed.