I try to visualize the Strahler-Order bigger than 8 using raster calculator.
I changed the style of the raster by changing the render type to singleband pseudocolor and, in the colors selector, I did not find boolean sentences. So, I created a new color map and classified it into two classes between 0 and 1 values.
However, it shows me just one small part of my raster (see Figure). The size of the data is as big as the original file. So, I assume that the calculation was properly carried out.