Add a close-up lens to the front of a normal lens.
This is the easiest way to get close-ups, the quality may suffer, particularly with the higher magnification close-up lenses but it is the easy-to-carry, cheap and cheerful way to get results. The equipment consists of filter like screw-in lenses that go on the front of the lens. Often they are called “dioptres” and may be called numbers like +1, +2, +4. The +number refers to the dioptre measurement of the lens and the higher the number, the greater the magnification possible. The dioptre measurement is the reciprocal of the focal length of the lens measured in metres. Therefore a +1 dioptre lens is 1 metre focal length, a +2 is 500mm and a +4 is 250mm. These add-on lenses are available in a variety of filter sizes and qualities. If you don’t wish to get heavily involved then a set of uncoated close-up lenses to fit your favourite lens is the way to go. Coated close-up lenses cost more and will yield a better image, and two element close-up lenses (much more expensive) will give better results particularly with longer tele type lenses.
The effect of these close-up lenses increases as you add them together. The +1 and the +2 screwed together will yield +3. Be aware that although you will get greater magnification, you will also get greater image deterioration. If you do try this the usual method is to put the strongest one closest to the lens then the lesser one. For the above coupling you would screw the +2 on first then add the +1 to that, then any filters or lens hoods.
The close-up lenses have more effect on longer focal lengths. Attached to a 50mm lens on the camera the +4 close-up will yield closer focussing but nothing amazing. Try a +1 close-up lens on a 200mm or 300mm lens and the effect is much more exciting.
This situation makes the decision of what thread size close-up set to buy a bit more interesting. If you intend to be mildly involved with macro using close-up lenses then it would be best to buy the set that fits your 70-200 or 75-300 lens then buy adapter rings to make the close-up lenses fit your other lenses with maybe smaller thread sizes. They are called step-up rings and are much cheaper than buying a second set of close-up lenses.
Even though I own macro lenses and bellows I also own a +2.9 coated double element close-up lens (expensive) that with the appropriate step-up rings will fit nearly all of the lenses that my wife and I own. The one close-up lens and the few lightweight step up rings take only a small space in the camera bag for those times I don’t want to carry the proper macro lens.
Upside. They are relatively cheap, are light and don’t take up much room in the camera bag and the normal camera internal TTL light metering takes them automatically into account and no adjustments are required.
Downside. More stuff added to light path adds more optical problems, flare, distortion etc. If used on tele lenses you really need to have the more expensive double element models that are also hard to find. The more powerful the close-up lens, the worse the image. Try to use around f/8 or f/11 on the lens to make the best of the situation.
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I was really interested in reading this article, because I now want to learn about how to use different photographic equipment to achieve new results. I want to try out many different things for my final year, and gain a lot more experience in different fields of photography.