Disadvantages of Close-Up Lenses
Of course, close-up lenses also have a couple of potential disadvantages:
- Your camera lens may not take a close-up lens. You may not be able to use a close-up lens on every camera lens that you own, due to differences in filter thread sizes. However, you can buy the largest close-up lens that you need and use stepping rings to attach it to lenses with smaller diameters.
- A close-up lens may not get you as close to the subject as a macro lens. For true macro photography, you need a magnification of 1:1 or more. A magnification of 1:1 is achieved when the subject is reproduced at life-size on the sensor or film. A subject that measures 36 mm across, for example, should take up an entire full-frame sensor (which also measures 36 mm across). You can only achieve 1:1 magnification when a close-up lens is used in conjunction with a telephoto lens (somewhere in the region of 300 mm or more)even then, your specific lens and close-up filter combination may not be powerful enough.