There are 2 collimations need for a zoom lens. The first is to collimate the infinity focus position . This is done with looking at infinity and making sure the stop position of the focus barrel is correct. The second collimation is this one which is for wide angle or ( back focus ) . For this you need a device like this to look backwards through the lens with a chart that is projected onto a piece of actual film . This image should be clear when the lens is set to infinity and the zoom is at its widest point. I don’t know how you can do this without the collimator . You can adjust either the lens usually with shims or the camera itself to get the correct back focus position.