Compare two different seismographs for same 6 hour period

On the slope of Kilauea are two seismographs that are relatively close together. One is positioned to the North and one to the South of a line where lava may erupt from the ground and inundate the neighborhood of Kapoho. On May 23, 2018 which seismograph was recording greater activity?

Use the two seismograph records saved for May 23, 2018

ERZ1 Seismograph on May 23, 2018

ERZ2 Seismograph on May 23, 2018

Answer:
Again this question only asked for a comparison on a relative basis. So a simple mean result from ImageJ will yield an answer:

                 Area        Mean
ERZ1 1090800 71.532 0 255 0 255
ERZ2 1090800 71.897 0 255 0 255

ERZ2 shows a higher volcanic tremor level than ERZ1

Question: Relatively how much higher?

In the previous question we established 92,664 pixels as being baseline noise. Subtracting these out we do the following math.

ERZ1 (1090800*71.532/255)-92,644=213,344 black pixels associated with activity

ERZ2 (1090800*71.897/255)-92,644=214.906 black pixels associated with activity

Delta = 0.73% 

ERZ2 activity level is 0.73% higher than activity level seen at ERZ1.