Maximum size of image that can be placed into a marker label. Jan 22, 2014 By Fiona Klassen I'm working on a flowchart with markers inserted at the points on the chart for my users to click on and open up the marker label to reveal some more info and an image. There seems to be a constraint on the maximum size of image that I can insert. I've tried resizing my image that I want to insert but when I insert they return to approximately 28 px x 28 px. Have I missed something or is there a limit built into a marker?