In my entomological work I often need to compare two images of bugs side-by-side.
Comparisons are surprisingly hard to do with either of the image viewers I normally use, namely Eye of Gnome and Ristretto. First I open two instances of the viewer and adjust their window sizes and positions for easy side-by-side comparison. I then open one image in one viewer window, and the other image in the other window. If I want to zoom in or out, or pan across the images, I have to do this independently in each viewer window. If I don't save this two-instance arrangement on a dedicated workspace using 'Save session on exit', I'll have to repeat the setting-up next time.
Comparisons are much simpler in Geeqie image viewer, which is now in most of the Linux distribution repositories. I first heard about Geeqie in 2011 when it was featured in a glowing online review. I hope this article adds to the glow.