Spitzer IRAC images with H I contours of NGC 3312 (top), NGC 3314a (center), and NGC 3314b (bottom) in units of stellar mass surface density. The right image is the binned version of the left image (see Section 2.3). The gray lines indicate the direction of ram pressure as suggested by either how far the lowest H I contours penetrate into the stellar disk (dashed), or by the approximate orientation of the H I tail (dot-dashed). See Section 3.1, Figures 2, 3 for more details.