Pentax 17-70 Review - An All Around Lens for Pentax DSLR Camera
The Pentax 17-70mm f/4 DA AL IF SDM or simply Pentax 17-70 lens is one of the first from Pentax to feature a universal or standard zoom. The lens covers a wide range of photography and is one of the very few which has a very low price tag. With a low price tag but high quality imagery and a "standard zoom" approach, this particular lens remains one of the favorites especially for amateurs. The lens has a universal big focal length range at a very affordable and low price.
The Pentax 17-70 has a focal length of 26-107mm in 35mm category while being used with Digital SLRs. The lens makes use of ED so that chromatic aberration is suppressed. It also has spherical elements included in it as well so that the spherical aberration is limited. The image circle was created in such a way that the smaller image recording area of the DSLRs can be matched. This allows for better quality pictures. The Pentax 17-70 lens incorporates the Quick Shift Focusing System as well which makes it switch from auto focus to manual focus instantly. Another main feature of the lens is that it makes sure of the supersonic motor's operation which gives the focus a smoother and quieter functioning.
Although it is impossible to exclude barrel distortion from lenses like this, Pentax have done quite a good job at suppressing it. You are bound to get some barrel distortion anyways but the rate is not that high and Pentax are to be appreciated for this. The weight of the Pentax 17-70 is just over a pound which makes it a bit heavy compared to other lenses around.
The lens mount of the Pentax 17-70 is made of metal while there is a significant amount of plastic used as well. Optical formula that is used in the lens is quite complex which are seventeen elements in 12 groups. ED elements as mentioned above have made it possible to reduce and lower chromatic aberration to an extent. Corner shading is not a big issue with this lens with the best results coming at 17mm. As far as the sharpness is concerned, it is quite satisfactory and produces sharp and crisp images.
Overall, the entire lens is a very commendable effort from Pentax. Chromatic aberration and light fallout aren't much of a concern with this lens. The lens also offers a photographer with versatility, as a wide range of images can be taken from the Pentax 17-70.
The Pentax 17-70 has a focal length of 26-107mm in 35mm category while being used with Digital SLRs. The lens makes use of ED so that chromatic aberration is suppressed. It also has spherical elements included in it as well so that the spherical aberration is limited. The image circle was created in such a way that the smaller image recording area of the DSLRs can be matched. This allows for better quality pictures. The Pentax 17-70 lens incorporates the Quick Shift Focusing System as well which makes it switch from auto focus to manual focus instantly. Another main feature of the lens is that it makes sure of the supersonic motor's operation which gives the focus a smoother and quieter functioning.
Although it is impossible to exclude barrel distortion from lenses like this, Pentax have done quite a good job at suppressing it. You are bound to get some barrel distortion anyways but the rate is not that high and Pentax are to be appreciated for this. The weight of the Pentax 17-70 is just over a pound which makes it a bit heavy compared to other lenses around.
The lens mount of the Pentax 17-70 is made of metal while there is a significant amount of plastic used as well. Optical formula that is used in the lens is quite complex which are seventeen elements in 12 groups. ED elements as mentioned above have made it possible to reduce and lower chromatic aberration to an extent. Corner shading is not a big issue with this lens with the best results coming at 17mm. As far as the sharpness is concerned, it is quite satisfactory and produces sharp and crisp images.
Overall, the entire lens is a very commendable effort from Pentax. Chromatic aberration and light fallout aren't much of a concern with this lens. The lens also offers a photographer with versatility, as a wide range of images can be taken from the Pentax 17-70.
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