This works exactly as described... you can mount your lens backwards and get extreme magnification from your normal lens. If you want to experiment with this, do a little research ahead of time so you know what to expect and what not to expect. I used my kit 18-55 lens on my Canon Rebel. My first attempt gave me an idea of the strength of the magnification but I didn't love the results. The problem was that I was trying to shoot with the lens wide open and hand held, with the ISO cranked up. This resulted in a depth of field so shallow that it was almost impossible to focus. For the second attempt, I set the lens to f22, didn't try to zoom in as close, and used a table top mini tripod so I could leave my ISO at 100. The exposure time was about 8 seconds with this approach and the results were much better. Pros: Convert a kit lens into a very powerful macro lens. Good fit. My kit lens isn't real heavy, but I never had any fear that it was in danger of falling off the camera due to being mounted backwards. If you have a heavy lens, just keep in mind that you are supporting the weight of the lens by the filter threads. Keep in mind that a shorter focal length gives you more magnification, so if you have a 35 or 50mm prime, you should have a good lens to start experimenting with. Cons: Well, there a lot of them, but I'm more than happy to put up with them, when you look at the cost vs. the results. BTW, this approach was recommended to me by a professional photographer who has several reversing rings for his macro work. So unless you are publishing prints for editorial work, this should be fine for web view or small prints. Here are some things to keep in mind: - You need a very firm setup where neither the camera nor subject is moving. (If you want to photo insects, they'll have to be dead ones.) - The "business" end of the lens is exposed, so you'll want to keep that rear lens cap handy (because now it's a front lens cap). And if you want to leave the lens in this state off the camera, you will need to buy yourself a spare rear lens cap. - The zoom is completely reversed, so 18mm will give you about 3x more magnification than 55mm. - Focus is very sensitive due to the shallow depth of field. Not only that, it's affected by three things: Your zoom setting on the lens (if you are using a zoom), your focus setting on the lens, and the distance between the lens and subject. - The field of view can be dark, blurry, and extremely limited, so it's easy to get "lost" when trying to focus in on your target. I found it helpful to point at the end of my target with my finger (which usually shows up as a big blurry shadow) and then follow that to the end to find where the target is. - With an automatic lens, you will need to first mount the lens in the normal orientation, set the aperture with the camera, then press the DOF preview button on your camera WHILE you remove the lens. This will leave the lens set at the aperture you dialed in (otherwise it reverts back to wide-open when you remove it). For this macro work, you'll need to stop down pretty far. I went with f22 to get a DOF range of about a quarter inch. - When screwing the adapter onto the filter threads of the lens, make sure it is fairly tight, otherwise when you go to remove the lens from the camera, the adapter will start to unscrew. - You have to shoot in manual mode so you can make sure that you have the right exposure. (There's no communication between the lens and camera, so the camera has no idea what the lens aperture is set to.) - Focus is by far the biggest challenge, you need to be able to slightly (and I mean very slightly) nudge the camera or target closer or farther apart in order to fine tune to get the focus you need. You will not be able to use the focus on the lens itself for these adjustments, it's THAT sensitive. You can search the web for focus rails, and some people have made their own. - The quality you get from this approach won't be as good as what you get with a real macro lens. But I didn't have $400 to throw at a macro lens, and I DID have $10 to try this out. For me, it was worth it just to explore this aspect of photography without the huge investment.
