| Canon EF 70-200 F4 L IS, one of famous | | | | diaphragm blades. Its maximum aperture (F-Stop |
| telephoto lenses of the photography world today, | | | | number) is 4 and its minimum aperture (F-Stop |
| is comprised of 4 main important parts which are | | | | number) is 32 throughout all focal length. |
| lens construction, a lens body, IS (Image Stabilizer | | | | Moreover, there is no an aperture ring at the |
| system) and an aperture. I have been using this | | | | back of the lens so the aperture must be |
| lens for awhile and I would like to share my | | | | adjusted by the camera only. Its functions are for |
| review into 4 important parts as listed below. | | | | controlling the amount of lighting coming into the |
| Firstly, the lens construction is composed of 15 | | | | image sensor and depth of field. |
| lens groups and 20 lens elements with a filter | | | | Finally, IS (Image Stabilizer system) contains a |
| diameter of 67 mm and it has a focal length | | | | special gyro system which shifts lens in the gyro |
| range from 70 mm to 200 mm. Moreover, there | | | | system in the opposite direction of hand shaking |
| are 2 UD (Ultra-low Dispersion) lens elements and | | | | both x-axis and y-axis in order to compensate |
| 1 fluorite lens element which help dramatically light | | | | vertical and lateral movement of hands while |
| dispersion, color balance, image sharpness and a | | | | taking photos. Consequently, the motion of IS will |
| vignette while minimizing ghosting and flare. It has | | | | cancel out hand shaking directions and the light |
| the closet focusing distance of 1.2 m and the | | | | coming into the image sensor will be steady. It is |
| maximum magnification of 0.21 m. It is used for | | | | very useful when photographers would like to |
| dispersing light reflected from objects into an | | | | take photographs in low shutter speed condition |
| image sensor in a camera. | | | | and it gives an equivalent effect of shutter speed |
| Secondly, with a total weight of 760 gram, the | | | | approximately 4 stops. With the IS, it helps |
| lens body has a diameter of 76 mm and a length | | | | considerably photographers get sharp images in |
| of 172. It has a strong white magnesium alloy | | | | low shutter speed condition. |
| case with black rubber cover at a zoom ring and | | | | In conclusion, the 4 main important parts of the |
| a focal ring and a red ring showing as the Canon | | | | Canon EF 70-200 F4 L IS lens which are the |
| professional lens, called L-series lens, around a | | | | construction, the lens body, the IS (Image |
| front part of the lens. It is used to protect the | | | | Stabilizer system) and the aperture make this lens |
| lens elements, the aperture, dust and moisture | | | | as the outstanding professional telephoto lens. You |
| from outside. | | | | can find great offers from Canon 70-200 F4IS |
| Thirdly, the aperture is made of 8 circular | | | | Price Comparison. |