Lens nikon af-s nikkor 24mm f1.4 g ed đánh giá
Released in February 2010, the 24mm ƒ/1.4G AF-S began a string of modern fast primes produced by Nikon, as it overhauled and improved its offering in this area. The 24mm lens is brand new to the lineup, the previously fastest, widest lens on offer from Nikon being the 28mm ƒ/1.4. The lens was designed with the FX sensor or 35mm film in mind, and is also compatible with DX-sized sensors. On those cameras, the lens will produce a field of view of approximately 36mm. The lens takes 77mm filters, ships with a petal-shaped lens hood, and is available now for approximately $2,200. Sharpness Mounted on the sub-frame D300s, the 24mm ƒ/1.4G produced slightly soft results wide open at ƒ/1.4. Slightly sharper performance was obtained by stopping down to ƒ/2, showing decent sharpness in the center and tapering off to light softness in the corners. It isn't until ƒ/2.8 that we start seeing very sharp results throughout the frame, with almost negligible softness in the corners; stopping down further provides only marginal improvements. The sharpest results are found at ƒ/5.6, but at that point we are seeing very slight differences between aperture. Diffraction limiting begins to appear on the D300s at ƒ/8, but it isn't until the lens is fully stopped-down at ƒ/16 that there's any practical impact on sharpness, where it still produces slightly sharper results than when used wide open at ƒ/1.4. Results were slightly different when the lens was mounted on the full-frame D3x. At ƒ/1.4 the lens is still slightly soft in the central region of the frame, moving to pronounced corner softness. Stopping down to ƒ/2 provides a light improvement to corner softness, and a corresponding increase in central sharpness, but it isn't until ƒ/2.8 that we start seeing impressive corner-to-corner sharpness. Stopping down to ƒ/4 provides maximum sharpness, though the differences between ƒ/4 through to ƒ/8 are minimal; we note some diffraction limiting at ƒ/11, and again, at ƒ/16 we still note excellent performance, perhaps not as sharp in the center than at ƒ/1.4, but certainly sharper corners. Chromatic Aberration CA tolerance in the 24mm ƒ/1.4 is very good, particularly when stopped down slightly. At wide apertures, we do note the presence of longitudinal chromatic aberration, which seems to be somewhat common in very fast glass - you can see it in our sample photographs as pink fringing on the edges of high-contrast areas. Stopped down past ƒ/4 it is slightly less of an issue. Shading (''Vignetting'') Corner shading isn't really a problem on the sub-frame D300s, with the only noteworthy results being extreme corners that are 1/3EV darker than the center, when set to ƒ/1.4. At any other setting, light falloff is insignificant. On the full-frame D3x however, it's somewhat more significant: at ƒ/1.4 light falls off to make the extreme corners over a full stop darker than the center; at ƒ/2, this falloff lowers to around 2/3EV. At ƒ/2.8, this falloff hovers at just over 1/3EV; at ƒ/4 and smaller apertures, falloff results are a quarter-stop or less, which isn't really significant. Distortion The 24mm ƒ/1.4G does fairly well to restrict distortion, showing a consistent +0.3% barrel distortion in the corners when mounted on the D300s. On the D3x, there's slightly more distortion, with a maximum result of +0.5%. Autofocus Operation The 24mm ƒ/1.4G uses an AF-S focusing motor, making it compatible with all modern Nikon camera bodies. Autofocus is fast, about one second to slew through infinity to closest focus, and is near silent. Autofocus results can be overridden at any time by just turning the focus ring. Macro The 24mm ƒ/1.4G makes a poor macro lens, with just 0.18x magnification and a minimum close-focusing distance of 25cm (just under a foot). Build Quality and Handling The 24mm ƒ/1.4G is fairly large for a prime lens, at 620 grams (just under 22oz). The balance feels good on larger cameras, but on smaller bodies, the weight of the lens makes the combination a bit front-heavy. The lens mount is metal and the 77mm filter threads are plastic. As the price point will attest, Nikon views this lens as fairly exotic, however it doesn't sport many premium features other than top-notch build quality. That said, it probably doesn't need things like a focus limiter or vibration control. Its only switch is an autofocus / manual focus selector; other features include a windowed distance scale, with a depth-of-field markings for ƒ/11 and ƒ/16. There is an infrared index, and the lens will focus past infinity. As you would expect, attached 77mm filters will not rotate on the front element. The 3/4-inch wide focus ring is rubber, a series of ribs running parallel to the body of the lens. A slight increase in resistance lets you know you've reached the end of the focusing distance, but the ring will continue to turn. There is no lens extension during autofocusing. The lens uses nine rounded diaphragm blades to make up the aperture, which should produce pleasing out-of-focus elements. The HB-51 lens hood around 1 5/8 inches in depth. The hood is a bayonet-mount that reverses onto the lens for easy storage, but denies access to the focus ring in this configuration. The lens is nicely resistant to obvious flare from bright light sources such as the sun, but the hood works well to reduce generalized veiling flare. Alternatives There aren't many alternatives in this category of lens. Nikon 24mm ƒ/2.8D AF ~$350 It certainly isn't as fast as the 24mm ƒ/1.4, but if you don't need the speed, for a lot less money you can get the angle. The 24mm ƒ/1.4 is indeed sharper all the way up to ƒ/5.6, where the ƒ/2.8 version of the 24mm lens suffers a bit from corner softness early on. Distortion and corner shading results are about the same; the 24mm ƒ/2.8 offers slightly better CA tolerance. Sigma 24mm ƒ/1.8 EX DG Aspherical Macro ~$550 We haven't yet reviewed this lens, but Sigma's offering comes fairly close in terms of the maximum aperture (only out by 2/3 of a stop). We've heard the lens suffers a bit from exceptional corner shading when used wide open, and autofocus is quite slow. Interestingly, the lens offers 0.37x magnification (hence the Macro designation). Nikon 28mm ƒ/1.4D ~$? We haven't reviewed this lens, but until the 24mm ƒ/1.4G came along this was the widest and fastest prime lens Nikon produced. It's been discontinued, and it still commands a high price in second-hand markets. Conclusion At $2,200, the expectations for this lens have to be high. The 24mm ƒ/1.4G almost reaches them. Certainly, stopped down, the lens produces exceptional results, but as the main feature of the lens is its extremely wide aperture - ƒ/1.4 - we imagine the lens will spend much of its time here, otherwise, it's much better on the pocketbook to get the ƒ/2.8 version of the 24mm lens. At ƒ/1.4, it's not tack-sharp, and corner softness is notable on FX lenses. But then, this isn't a lens you buy to shoot test charts, it's a lens you buy to get a unique perspective in your photographs, and you'll definitely want to try it before you buy it, if you can. Product Photos Sample Photos The VFA target should give you a good idea of sharpness in the center and corners, as well as some idea of the extent of barrel or pincushion distortion and chromatic aberration, while the Still Life subject may help in judging contrast and color. We shoot both images using the default JPEG settings and manual white balance of our test bodies, so the images should be quite consistent from lens to lens. As appropriate, we shoot these with both full-frame and sub-frame bodies, at a range of focal lengths, and at both maximum aperture and ƒ/8. For the ''VFA'' target (the viewfinder accuracy target from Imaging Resource), we also provide sample crops from the center and upper-left corner of each shot, so you can quickly get a sense of relative sharpness, without having to download and inspect the full-res images. To avoid space limitations with the layout of our review pages, indexes to the test shots launch in separate windows. Nikon24mm f/1.4G ED AF-S NikkorNikon 24mm f/1.4G ED AF-S Nikkor User Reviews9.6/10average of 8 review(s) Build Quality9.0/10 Image Quality9.8/10
10 out of 10 pointsand recommended by genotypewriter (12 reviews) Far/infinity IQ Close distance IQ (see my review link below), current price is a bit unfair when comparing to the Canon 24L II Here is my detailed review of the Nikon 24mm f/1.4G compared to the Canon 24L f/1.4 II (both on a 5D MkII): |