One of the first things I learned on my personal journey of acquiring the skills of technical analysis was the distinction between the logarithmic scale and the linear scale.
The often recited rule of thumb for when charting on the logarithmic is that it is prescribed for detecting patterns and drawing inferences on higher time frames.
Why this tends to aid the technical analyst is clear when one appreciates the manipulation to the price index that toggling "Log" initiates.
According to Investopedia.com:
Logarithmic price scales cause "commonly recurring percentage changes to be represented by an equal spacing between the numbers in the scale. For example, the distance between $10 & $20 is equal to the distance between $20 & $40 because both scenarios represent a 100% increase in price."
It became immediately understandable why the recommendation of Log was suited for any charting done on higher time scales (personally interpreted as anything over a week).
For it tends to lessen the distorting effects of outliers (euphoria & blackswan events).
As a recent example I would like to single out the call made on the weekend on an impending break of trend on $ADA, which using the Log chart you would have caught at ~44¢ as opposed to the ~47¢ break of trend which occurred on the linear.
The exact charts with Log on and without
Logarithmic
LinearSee any differences?

