Posts Tagged ‘angle of view’
Scout, the first Lensbaby lens that does not bend, features the Fisheye Optic, which delivers an ultra-wide 12mm focal length capable of capturing a 160 degree angle of view from infinity all the way down to 1/2 inch from the front of the lens. The Fisheye Optic can also create unique flare effects in an image.
“The Scout is for adventurous photographers wanting an easy to use fisheye lens combined with the creative freedom of the Lensbaby Optic Swap System,” said Craig Strong, Lensbaby president and co-founder. “We chose to combine the straight-shooting, non-bending Scout with our 12mm Fisheye Optic so that Lensbaby users could have a simple, affordable, and fun way to play with the Fisheye’s creative flare and eye-opening close focus.”
Due to the extremely wide angle of view of the Fisheye Optic, full frame shooters will generally see a black circle around almost the entire image, and APS-sized sensor shooters will see black at the corners of their images. With Scout, the Fisheye image is always ideally situated in the center of the frame.
Since their image circles do not need to cover the entire traditional 35mm film area (24×36mm), these DX lenses are less expensive to produce and can be smaller. Sometimes they can also cover a wider zoom range.
The first DX lens Nikon introduced was the AF-S 12-24mm f/4G, which helps DX DSLR users regain the super-wide angle of view. It has been very popular among landscape, building interior, and wedding photographers as well as anyone who needs a wide lens. Since then, several third-party lens manufacturers such as Sigma, Tamron and Tokina have produced various 12-24, 11-16, and 10-20mm DX-type lenses. In such super-wide range, each extra 1mm will make a noticeable difference. The new AF-S 10-24mm f/3.5-4.5 G DX zoom from Nikon helps them push further on the wide end as some of their competition have.
While a very good lens overall, the original 12-24mm f/4 DX is excellent on the long (24mm) end but somewhat mediocre around 12mm. Well known Norwegian Nikon expert Bjorn Rorslett once called it the best 24mm he had tested. However, on the 12mm end, there is noticeable distortion and loss in quality. A few years later in 2007, Nikon introduced the 14-24mm f/2.8 AF-S, which can cover the entire FX (24×36mm) frame and is excellent all the way down to 14mm.
It will be interesting to see whether Nikon manages to improve the overall quality in the 10-24mm to match the 14-24. One welcome news is that while the 14-24mm f/2.8 has a bulging front element so that no filter is possible, the new 10-24mm will continue to accept 77mm filters. Compared to the original 12-24mm f/4, the constant aperture has become slightly variable from f/3.5 to 4.5
- Focal length 10-20mm
- Aperture f/4-5.6
- Angle of view 102.4-63.8°
- Filter size/type 77mm
- Construction Elements/groups 14 elements in 10 groups
- Focusing type Internal HSM
- Closest focus 0.24m
- Weight 0.470kg
- Dimensions (Dia x length) 83.5x81mm
- Mounts available Sigma, Canon, Nikon(D)
- Tripod bush No
- Price (SRP) £369.99
Build and handling
This lens is designated to, and joins Sigma’s EX range. It therefore comes with the three year UK warranty and is shipped with a lens hood in a zip-topped pouch of the type that now sports a belt loop. The finish is the hardy matt black that we’ve praised before. Canon and Sigma mounts sport the usual AF/MF switch while the Nikon hasn’t. Both are straight in front of the mount. The remainder of the barrel is split approximately into thirds, the first and last third being occupied by zoom ring and focus ring. The zoom ring is marked at 10, 12,14, 17 and 20mm. Zooming extends the lens length by barely 5mm, so a zoom lock would be fairly superfluous!
Focus is achieved with a silent HSM motor, which does not have to move the elements very far, and therefore is almost instant. The front element does not rotate during use, making filters easy to use.
Sigma have done a good job here, with the lens sporting a 77mm filter thread, not a huge size for an optic this wide. And the front element does not protrude, so that close fitting filters can be used.
We tried a Cokin Z-Pro system on the lens and found that, fitted normally, there was no vignetting if the holder was oriented in the same way as the hood is fitted. However, it did vignette at 10mm with the holder in a normal position when taking landscape shots. (Disappears between 11 and 12mm) With the holder reversed, leaving just the single slot, this problem was overcome. Sigma does state in their multi-language leaflet that only one filter should be used and thicker ones ‘may’ cause vignetting.
This lens is sharp! At 20mm, resolution tests showed it matched, and at one point even slightly out performed the venerable Canon 17-40mm L.
At 15mm it’s a little soft at the edges, although still nice in the centre, but by the time it gets down to the 10mm mark the edges have improved again. In fact, at the wide end, the overall performance was the best in the range. The lens has obviously been optimised for the shorter focal length as there was no distortion there, whereas the 20mm end did have a little pin-cushioning.
Chromatic aberrations have been very well controlled with the employment of three SLD (Special Low Dispersion) elements, one moulded aspherical and two hybrid aspherical elements. Although not completely eliminated, they did not show up significantly.
The lens is designated as a DC, meaning that it’s designed exclusively for dSLR cameras with a crop factor of 1.5x or greater. However, we did try it on a Canon 1D, which has a crop factor of 1.3x and found that, without filters, it could be used from 11mm upwards without vignetting. (From Photodo.com)