Add a Reversing Ring to a Zoom Macro Lens
A reversed zoom lens gives you the option to choose from a variety of focal lengths at a close-up range. You can reverse a lens and fix it to your camera body with a reversing ring. This makes it possible to use a zoom macro lens, rather than a fixed lens, for close-up photography.
Reverse your zoom lens and experiment with how it works at different focal length settings and try adjusting your focusing ring at each focal length to see how they work with each other to affect the focusing distance and magnification of your subject.
With a 28mm to 135mm zoom macro lens, you can achieve multiple levels of macro and close-up photography:
Reverse the lens and set it to its widest focal length to achieve the greatest amount of magnification. A reversed 28mm lens provides a representation of your subject that is greater than 1:1. The subject is larger than life-size on the digital sensor.
When reversed, wider focal lengths (such as 28mm) enable you to achieve focus within only a small range of distances from the subject. Rotating the focusing ring has a minimal effect on changing your focusing distance.
With the lens reversed and set to its mid focal length, you get less magnification than you do with the widest focal length setting. You also get a larger range of focusing distances when you adjust the focusing ring.
A reversed lens at the lens’s longest focal length setting gives you less magnification and enables you to focus when you’re farther from your subject. You get a greater range of focusing distances when you adjust the focusing ring.