This 12-24mm ultra wide-angle zoom lens is designed for DSLRs with an APS-C sized sensor and has a fixed f/4 maximum aperture throughout its zoom range.

Like its predecessor, the AT-X 124 PRO DX II features the one-touch focus clutch mechanism. It allows for a fast and easy manual over-ride in difficult lighting situations. To use this feature you simply move the focus ring forward, towards the front of the lens, for AF or back for MF.

The optical system of the original lens is renowned for its sharpness and the new version has been improved further by the introduction of a new multi-coating system. This new coating helps reduce reflections that can cause flare and ghosting.

The Nikon mount AT-X 124 PRO DX II features a built-in AF motor drive that operates smoothly and quietly due to a DC motor that uses a new AF control gear assembly. With the built-in motor, the lens can be used in AF mode with the Nikon D40, D40x, D60 and D5000 bodies, which lack a body-integral focus motor.

Tokina AT-X 124 PRO DX II Lens – Specifications:

• Focal length: 12-24mm
• Maximum Aperture: F/4
• Minimum Aperture: F/22
• Optical Construction: 13 Elements / 11Groups
• Angle of view: 99 - 61°
• Minimum Focus Distance: 11.8 in. (30cm)
• Macro Ratio: 1:8
• Aperture blades: 9
• Filter Size: 77mm
• Lens diameter: 3.46 in. (84mm)
• Total length: 3.5 in. (89.5mm)
• Weight: 19.0 oz. (540g)
• Included Accessories: BH-777 Star bayonet hood

According to http://www.kenro.co.uk.

The Tokina AT-X Pro SD 12-24mm F4 (IF) DX is a wide-angle lens designed for APS-C/DX format DSLRs only and is available for Canon and Nikon mounts.  It has 18-36mm equivalent zoom range on a 35mm film camera and  maintains a bright constant aperture of f/4.

The 12-24mm reveals an optical formula of 13 elements in 11 groups, which features 2 aspherical elements plus SD glass elements to combat aberrations. Chrome plated brass mount plate and all-metal zoom unit with advanced polycarbonate outer lens barrels make it a pleasure to carry.

This solid, well-built lens has excellent operational characteristics; the zoom and focus rings are impressively smooth. And one other outstanding feature is a one-touch focus clutch mechanism, which allows you to switch from auto to manual focus simply by pulling the focus ring towards the camera.

Tokina has recently updated this lens. The new ‘II’ model adds an autofocus motor for Nikon users (allowing AF on the D40 / D40X / D60 bodies). It also features improved coatings to reduce flare. So, these changes are relatively minor and Canon users will benefit only from the new coatings.

In the review by dpreview.com they state: “It’s simply a very sharp lens, especially wide open, delivering consistently good results at almost all settings; it also scores well with respect to its distortion and falloff characteristics. These characteristics, coupled with the constant F4 maximum aperture, make it much better suited to shooting interiors or in low light than similar lenses.”

They mention that only lateral chromatic aberration can also be problematic. And imaging performance at very close focus distances is not particularly good.

Tokina AT-X Pro SD 12-24mm F4 (IF) DX - Specifications:

• Focal Length: 12-24mm
• Focal Length Equivalent: 18-36mm (1.5x DX); 19-38mm (1.6x APS-C)
• Diagonal Angle of View (APS-C): 99º - 61º
• Maximum Aperture: F4
• Minimum Aperture: F22
• Lens Construction: 13 elements in 11 groups including SD glass elements and 2 aspherical elements
• 9 Diaphragm Blades
• Minimum Focus : 0.30m
• Maximum Magnification: 0.13x
• Micro AF Motor
• Internal Focus
• Filter thread: 77mm
• Supplied Accessories: Front and rear caps, Lens Hood BH-777
• Weight: 570 g (20.1 oz)
• Lens Mount: Canon EF, Nikon F
• Street price: $490 ($580 for ‘II’ version)

According to http://www.tokinalens.com.

The Tokina AT-X 16.5-135 DX, is a 16.5-135mm f/3.5-5.6 AF lens is a new lens that gives the digital photographer an ultra wide-range zoom lens that has the equivalent angle of view to a 25-200mm. It is designed exclusively for digital SLR cameras with APS-C sized CMOS and CCD sensors (DX) – not for cameras with full frame sensors (FX).

This Tokina compact super wide zoom range begins at 16.5mm and offers the photographer a wider angle of view in comparison with most lenses in its class that start at 18mm. So it suits better for scenic and travel photography in as well as most general photography situations.

The AT-X 16.5-135 DX’s three aspherical elements, one all glass precision-molded element and 2 compound elements work for high contrast. Two Super-low Dispersion (SD) glass elements correct chromatic aberration. In addition, its newly designed high-precision mechanical zoom cam system minimizes play and eliminates zoom creep.

The lens will be available for Nikon cameras in June, for Canon cameras – in July.

The Tokina AT-X 16.5-135 DX – Specifications:

• Focal Length: 16.5 - 135mm
• Maximum Aperture: F/3.5-5.6
• Minimum Aperture: F/22
• Construction: 15 elements in 9 groups.
• Coatings: Multi-layer coating
• Angle of View: 81° - 12°
• Minimum Focus Distance: 19.7 in. (0.5m)
• Focusing system: Internal focusing
• Macro Ratio: 1:5.43
• No. Aperture blades: 9
• Filter Size: 77mm
• Lens diameter: 3.46 in. (84mm)
• Total length 3.1 in. (78mm)
• Weight:: 21.5oz. (610g)
• Accessories: Star bayonet hood (BH777)
• Mount Availability: Nikon DX digital/CANON DX digital

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