Tamron AF 18-200mm f/3.5-6.3 XR Di II LD Aspherical (IF) Macro Zoom Lens for Pentax Digital SLR Cameras

The new AF18-200mm F/3.5-6.3 XR Di-II LD Aspherical (IF) MACRO is a high power zoom lens for exclusive use with digital (APS-C size) SLR cameras that inherits the product concept of the existing AF28-300mm F/3.5-6.3 XR zoom lens. Even two years after its introduction, the current AF28-300mm is still a much loved and highly evaluated by photographers around the world as a representative model of high power zoom lenses. With the market influx of digital SLR cameras in recent years, the use of high power zoom lenses has become increasingly popular since high power zooms provide the convenience of handling many photographic scenes and the capability of shooting ultra telephoto shots without changing lenses. The popularity of this focal length led Tamron to initiate the development of new zoom lenses to further meet the needs of digital SLR photographers.

Brand: Tamron Model: Pentax AF Dimensions: 9.00" h x 9.00" w x 9.00" l, .88 pounds Lenses are designed for exclusive use on digital cameras with smaller-size imagers Not designed for conventional cameras and digital cameras with image sensors larger than 24mm x 16mm Concept of our high-power zoom lens For exclusive use with digital SLRs Most compact 11.1X zoom lens made for digital SLR cameras

Tamron's original development of proprietary core technologies such as Aspherical element production, Multiple Cam Mechanism and Integrated Focus Cam design lend to the creation of the world's lightest, most compact 11x zoom lens made for digital SLR cameras. Zoom in for a macro shot AF18-200mm F/3.5-6.3 XR Di II Highlights Di II Lenses are designed for exclusive use on digital cameras with smaller-size imagers and inherit all of the benefits of our Di products. These lenses are not designed for conventional cameras and digital cameras with image sensors larger than 24mm x 16mm. Extra Refractive Index Glass (XR) Special glass for better performance and more compact lens designs Extra Refractive Index (XR) glass can bend light rays at steeper angles, thereby decreasing the physical length of the lens while enhancing imaging performance by minimizing optical aberrations. This has allowed Tamron to develop a line of shorter, smaller-diameter, lighter lenses without sacrificing lens speed, and actually upgrading image quality compared to older designs. XR glass is costlier than conventional glass but it yields enhanced optical power distribution, making possible many of the outstanding and innovative lens designs that bear the XR designation. XR glass, with its superior light-bending power, makes it possible to design a short-barrel lens with the same light-gathering ability (aperture value) as a long-barrel lens—even with a smaller lens diameter. By using this principle Tamron has been able to shorten the length of the entire optical system and produce lighter, more compact lenses of the same speed, and also to provide greater zoom ranges in lenses that are much more convenient to carry by hand. Low Dispersion (LD) Low dispersion (LD) glass elements in a lens help reduce chromatic aberration; the tendency of light of different colors to come to different points of focus at the image plane. Chromatic aberration reduces the sharpness of an image, but glass with an extremely lowdispersion index, has less of a tendency to separate (defract) a ray of light into a rainbow of colors. This characteristic allows the lens designer to effectively compensate for chromatic aberration at the center of the field (on axis), a particular problem at long focal lengths (the telephoto end of the zoom range), and for lateral chromatic aberration (towards the edges of the field) that often occurs at short focal lengths (the wide-angle end of the zoom range.) Low Dispersion (LD) Glass for Greater Lens Sharpness Internal Focus (IF) Internal focusing (IF) provides numerous practical benefits to photographers including a non-rotating front filter ring that facilitates the positioning of polarizing and graduated filters, and more predictable handling because the lens length does not change during focusing. Even more important, Tamron’s Internal Focusing (IF) system provides a much closer minimum focusing distance (MFD) throughout its entire focusing range. In addition, IF improves optical performance by minimizing illumination loss at the corners of the image field, and helps to suppress other aberrations that become more troublesome at different focusing positions. Zoom Lock Another original Tamron mechanical engineering concept is the Zoom Lock (ZL), a simple convenience feature that prevents undesired extension of the lens barrel when carrying the camera/lens unit on a neck strap.

Customer Reviews more useful 39 of 39 people found the following review helpful. Good quality, good price, excellent versatility by William Porter Before buying my Pentax K100D, which I already used all three models of the Canon Powershot S-series 'super zoom' lens fixed cameras (S1, S2 and S3). I love my Pentax digital SLR too, but after I bought (and sold my Canon) I miss the versatility of the Canon. I've recovered most of that versatility with this lens Tamron 18-200 DIII, which is good at wide end, right in the middle and also very good at telephoto (I like photographing birds) and it still offers a macro capability. This is now my standard lens for all purposes. Not the best choice for shooting in low light, but when the light is decent, or you can use a flash, this is a good lens, takes good pictures and is a very good price. To do noticeably better than that, you need to pay much more likely to give up the versatility, too. I give the lens a rating of four stars instead of 5 only because, by nature, this is a bit of a compromise lens, if you do not have the versatility - for example, if you do not really need focal lengths below 70mm - then you can a lens with some great quality for the same price or even less (perhaps much less if you buy used). Pentax 50-200 is a bit sharper at telephoto. My Sigma 28-70 F2.8 is faster in its line-up (maximum aperture of the Tamron is 3.5). And while it's good for my needs, deserves this macro lens just to mention a generous sense. But as a package, it is hard to beat. 14 of 14 people found the following review helpful. Tamron 18-200 for Pentax and P. Neis I'm happy. Worth the price. It is compact and lightweight. Will do portraits at 18mm and zoom of birds and distant subjects. It's also pretty good for macro photography - tried a few butterflies and small insects. Problem: Need a lot of light. Can not manually control the opening of the lens (most people can only worry about) 18 of 20 people found this review helpful. With big goals Month Bum This is a fantastic goal and I am very pleased with the results I get. Sharpness and clarity is on par with plus lenses made of high-end cameras (I have my Nikon D80 compared to a 18-200mm). I bought it because it is a hazel to bring lots of lenses. Changing the lens carries the risk of getting dirt and dust inside the camera body. If tiny particles get on the mirror, as shown in the picture and must be removed with a computer. Although I have a Pentax K10D, I just do not want to take the risk. The hood is a bit "bulky to carry, while 'I solved with a collapsible rubber hood. I do not think the problem is to remove a star. The second major part of this lens if you use manual focus, which flashes red" points "when you go beyond the point of proper focus. After discovering that report, most of the filming was done manually, except for fast-action scenes and macro moving objects and backgrounds are all hand now.Pentax K10D 10.2MP Digital SLR Camera with Shake Reduction and 18-55mm f / 3.5-5.6 See all 19 customer reviews ....