Whereas the erection in the previous picture has a u-curve, the upward pointing erection in this picture has a slight n-curve.  In my experience most n-curves are on erections that are horizontal or below - so this high n-curve may be relatively rare.  We don't know how rare because the samples of men that have been studied are not large enough to tell.  In the photo research about 15% of erections had an n-curve, and all but this one were horizontal or below.  The male in this picture is age 32, 6 ft., and 175 lbs.