Humidity sensors are typically made of alpha-alumina films as porous dielectric materials deposited through the anodic spark deposition (ASD) technique, a unique anodic oxidation method to deposit ceramic coatings on the exterior of metals. Close attention to the precise composition of electrolyte solution is crucial when mixing chemical compounds. Moreover, the ASD process, which happens during dielectric breakdown at the anode surface in an electrochemical cell, is clearly followed by visible sparking at the anode/electrolyte interface, leading to the formation of various ceramic coatings on metal substrates. Electrical breakdown happens over an anodized barrier layer, typically amorphous aluminum oxide, which has been produced on the metal anode. The local high temperature (>2000°C) produced by electrical sparks melts the amorphous aluminum oxide and converts it to alpha-aluminum oxide, forming the stable foundation for a reliable humidity sensor.In this study, we produced a variety number of small pores to investigate the response speed of moisture sensors. The ASD current can be adjusted to control the number of small pores. The smaller current gives a greater number of small pores. We focused on low-humidity sensors, often referred to as dew-point sensors. In fabrication of dew-point sensors, Scanning Electron Microscopy (SEM) was used to examine and determine the size of pores. Three different currents, 30 mA, 25 mA, and 10 mA, have been tried for comparative analysis of small pores existing within large pores. Two pores have been measured for current 10 mA, resulting in sizes of 47 nanometer (nm) and 71 nm, respectively. Similarly, three small pores for current 30 mA were measured with sizes of 32 nm, 42 nm, and 31 nm respectively. After the testing of low-humidity (dew-point) sensors, we found that the number of small pores does not significantly affect the response speed of the sensors.