Pentax SMC P-DA Fish-Eye 10-17mm f/3.5-4.5 ED Lens Review

Handling and Features
Performance
Verdict
Specification


This strange lens offers the distorted view of a fisheye lens, with the convenience of a zoom lens. It offers a 180degree field of view, from corner to corner when set at 10mm and the equivalent of a 25.5mm lens on a 35mm camera, with lots of barrel distortion, at 17mm. Some people may realise that this lens looks identical to the Tokina 10-17mm fisheye zoom available for Canon and Nikon mounts. Both lenses share the same optics, but the Pentax version is different in terms of design and build.

Pentax SMC P-DA Fish-Eye 10-17mm f/3.5-4.5 ED (IF) Handling and Features

Build quality is very good indeed with high quality plastics used for the construction of the lens barrel and a metal lens mount. The lens is compact, being only 71.5mm long and only weighs around 320g. As a result balances well with the Pentax K-5 IIs body used for testing.

Focusing is performed internally, so the lens barrel does not extend during focusing. Being a fisheye lens, with such a wide field of view, it is impossible to mount filters on the front of the lens. A petal shaped hood is built into the front of the lens which helps to protect the front element from bumps and scrapes, if nothing else.



The manual focusing ring rotates during auto-focus, so care may need to be taken to avoid it catching your fingers as it moves back and forth. Manual focusing action is smooth although there is little resistance from the focus ring, which can make applying fine adjustments troublesome. The Pentax 'Quick Shift' focusing system has been implemented on this lens, which means manual adjustments can be applied once the lens has focused automatically. Auto focus is screw-driven, so it generates more noise than newer silent focusing lenses do. Focusing is swift, as you might expect from such a short focal length lens.

The minimum focus distance of 14cm is typical for a lens of this type and it is close enough for really making the most the distorted perspective produced by fisheye lenses used at close quarters.

Pentax SMC P-DA Fish-Eye 10-17mm f/3.5-4.5 ED (IF) Performance

At 10mm, sharpness isn't really the strong point of this lens. Even so, performance in the centre is very good from maximum aperture. Unfortunately the same can't be said about the performance of this lens towards the edges of the frame, which starts off poor at maximum aperture and only increases to fair levels of clarity as the lens is stopped down.

At 14mm, this lens doesn’t perform much better. Centre sharpness is greatly reduced at all apertures, and the clarity recorded towards the edges of the frame isn't much better. However, stopping down to f/8 does result in outstanding sharpness in the centre of the frame.

Finally, at 17mm, sharpness in the centre improves to very good levels again at maximum aperture, and clarity towards the edges is fair. Stopping down to f/8 improves performance in the centre of the frame to outstanding levels once again, although sharpness towards the edges of the frame falls behind somewhat.

MTF@10mm

MTF@14mm

MTF@17mm

How to read our charts The blue column represents readings from the centre of the picture frame at the various apertures and the green is from the edges. Averaging them out gives the red weighted column. The scale on the left side is an indication of actual image resolution. The taller the column, the better the lens performance. Simple. For this review, the lens was tested on a Pentax K-5 IIs using Imatest.

Chromatic aberrations are very high at 10mm, exceeding 2.5 pixel widths towards the edges of the frame. This level of fringing will cause problems along high contrast edges in large prints or in harsh crops from the edges of the frame.

CA@10mm

CA@14mm

CA@17mm

How to read our charts Chromatic aberration is the lens' inability to focus on the sensor or film all colours of visible light at the same point. Severe chromatic aberration gives a noticeable fringing or a halo effect around sharp edges within the picture. It can be cured in software. Apochromatic lenses have special lens elements (aspheric, extra-low dispersion etc) to minimize the problem, hence they usually cost more. For this review, the lens was tested on a Pentax K-5 IIs using Imatest.

Falloff of illumination is well controlled with the corners of the frame only being 1.27 stops darker than the image centre at 10mm and at 17mm the corners are 0.5 stops darker. Visually uniform illumination is achieved with the lens stopped down to f/5.6 or beyond throughout the zoom range.

Distortion is as you might expect from a fisheye. Using a fisheye lens will always be a creative choice, where the distortion is used to enhance your image.

During testing, this lens proved itself very resistant to flare and contrast stays strong, even when shooting into the light.

Pentax SMC P-DA Fish-Eye 10-17mm f/3.5-4.5 ED (IF) Sample Photos

Value For Money

Being priced at around £300, this lens is quite well priced for a lens from a camera manufacturer. By comparison, Sigma offers a 10mm f/2.8mm fisheye lens, which lacks zoom, but sports a slightly faster maximum aperture and silent focusing, but costs around £480.

Pentax SMC P-DA Fish-Eye 10-17mm f/3.5-4.5 ED (IF) Verdict

This quirky lens may not be the best performing lens available, but then that may not be the point with an optic like this. Sharpness is good in the centre of the frame, for the most part, it is just the performance towards the edges that lets this lens down. Even so, it's a fairly inexpensive way to get a fisheye optic for you Pentax camera, which must be this lens' biggest selling point.

Pentax SMC P-DA Fish-Eye 10-17mm f/3.5-4.5 ED (IF) Pros

Good sharpness in the centre at either end of the zoom range
Compact and reasonably lightweight
Inexpensive
Good build

Pentax SMC P-DA Fish-Eye 10-17mm f/3.5-4.5 ED (IF) Cons

Lacklustre performance towards the edges of the frame
High levels of CA

FEATURES
HANDLING
PERFORMANCE
VALUE FOR MONEY
VERDICT

Pentax SMC P-DA Fish-Eye 10-17mm f/3.5-4.5 ED (IF) Specifications

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