Resolution

Resolution determines the number of frequencies at which analysis calculations will be performed.

If a Linear frequency scale has been selected, the Resolution sets the size of each frequency step after the Start frequency.  Lower values of Resolution produce calculation results at more frequencies, but at the expense of greater calculation time and greater memory usage.

If a Logarithmic frequency scale has been selected, the Resolution sets the multiplier by which each frequency after the Start frequency is multiplied.  Higher values of Resolution produce calculations at more frequencies, but at the expense of greater calculation time and greater memory usage.

More:

How EMI Analyst Assigns Frequencies