Thought I would offer up something someone told me back when there was no automatic anything on a camera. Back when you had to learn to operate a camera and a handheld light meter (not photoshop), before . . . well, I digress.

When shooting a handheld 35mm camera, the focal length of the lens is the denominator in the slowest shutter speed at which you can expect to get images that are not blurred. For example, with your 50mm lens, your slowest safe shutter speed was 1/60; with your 135mm, you could probably get away with 1/125th of a second.

[I'm an old fossil. I picked up a camera the day after they picked the color for dirt, back when we all shot fixed focus lenses because they were sharp and the zooms that were available just made mush. I still say nothing beats a medium or large format 'chrome! Glad I learned on old manual film equipment, which most would now call crap.]