A log axis is one that has uniform log-dimension increments over the graph. It can be either x-oriented or y-oriented. The following figure shows a x-oriented log axis.
The most common type of log axis is the full-cycle format which has uniform increments in the log-range space and has ticks at integral values of that space.
If you specify a axis values less than 1.8 cycles in the log-range space then the axis will format as a sub-cycle graph where the major tick increments are uniform in the domain space of the log mapping. The figure below shows a graph whose x-axis is in sub-cycle format:
The x-axis of the following graph is also in sub-cycle format, but with major ticks starting at the axis limits.
When entering axis-tick values in the inspector editor make sure to enter the values in linear units, except for the tick increment in full-cycle format. That increment is specified in the range unit of the log mapping. That is the only way to specify a uniform increment for the full-cycle format.