Tamaño de la imagen de marco completoLos lentes que crean imágenes de tamaño APS-C se diseñan sólo para cámaras digitales. No se pueden usar en cámaras que tienen un sensor de imagen más grande que el formato APS-C. Estos lentes tampoco son adecuados para cámaras de película. Sin AF UltrasónicoLos lentes con mecanismo de enfoque ultrasónico en general son más silenciosos y rápidos que los lentes de enfoque tradicional. No stepping motor AFLenses with stepping motor focusing mechanism are better for contrast based focusing, and are quiter and faster than traditionally focusing lenses. No se usa elemento de lente de Baja DispersiónLos elementos de lente de Baja Dispersión tienden a reducir la aberración cromática. Sin estabilizadorLa estabilización de imagen ayuda a reducir el difuminado causado por el movimiento de la mano, especialmente con una longitud focal grande o en situaciones con poca luz. La estabilización de imagen puede dar una ventaja de 1 a 3 paradas sobre lentes sin estabilización, basado en la regla de reciprocidad. Montura metálicaLos lentes más baratos generalmente vienen equipados con montura plástica, mientras que los lentes profesionales más costosos tienen montura metálica. En general, las monturas metálicas duran más, y es algo útil cuando se cambian los lentes con frecuencia. Cuando una cámara se usa generalmente con un lente, el material de la montura de los lentes no es importante. Sin Enfoque InternoLos lentes de enfoque interno no cambian su tamaño al cambiar el enfoque. El frente de la lente es fijoEl frente de lente fijo no rota durante el zoom y/o el enfoque. Esto permite al fotógrafo utilizar capuchas de lente en forma de pétalos. Los lentes de frente fijo también facilitan el uso de filtros de polarización. Tiene soporte para filtros de sustituciónLos filtros de sustitución se usan en aquellos lentes donde el lente frontal es demasiado grande, o el campo de visión no permite el uso de filtros tradicionales al frente de los lentes. Generalmente los lentes de ultra gran angular y telefoto brillante admiten este tipo de filtro. |
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Montura(s) disponible(s) | Canon EF, Nikon F, Pentax K, Sony / Minolta A, Sigma |
Aplicación(es) | Acercamiento, Paisaje, Efectos especiales |
Categoría(s) | Lente de pescado, Foto fijo ultra angular |
Multiplicador | 1× |
Estabilizador | no |
Longitud focal | 15 mm (foco fijo) |
Construcción de lentes | 7 elementos en 6 grupos |
Ángulo de visión |
35mm: 180° digital: 98° |
Número de cuchillas | 7 |
Apertura máxima | f/2,8 |
Apertura mínima | f/22 |
Distancia focal mínima | 15 cm |
Aumento | 0,33× |
Tamaño del filtro | N/D |
Tamaño | ∅ 73.5 × 65 mm |
Peso | 370 g |
Notas |
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Velocidad de AF | N/D |
Sonido de AF | |
Enfoque interno | no |
Zoom interno | N/D |
Lentes de frente fijo | sí |
Tipo de montura | metal |
Sellado para clima | N/D |
Filtro de sustitución | sí |
AF Ultrasónico | no |
Stepping motor AF | no |
Círculo de tamaño APS-C | no |
Elemento de lente de baja dispersión | no |
Estuche rígido | N/D |
Estuche suave | N/D |
Capucha para lentes | N/D |
Adaptador de trípode | N/D |
6 de mayo de 2007
Hi, I just wanted to give this lens a fair review. As the other reviewer mentioned, if you use it with an APS-C sensor digital slr, you won't see a whole lot of distortion. It's no different from the Canon brand fisheye on a camera like that. But, if you use it with film, or with a larger sensor size camera, full-frame if possible, it's really quite a beautiful, sharp, and very fish-eyed lens. On a Canon 5D it performed really well for me. I just wanted to say that on the right camera, it's really quite a lens.
5 de julio de 2007
This is an excellent lens that does exactly what it's supposed to do. Optically, it's also excellent. You need to think seriously about whether you know what you're doing or anything about photography if you buy this for a Canon digital camera that's less than full frame.
You should probably stick to point and shoots until you understand lens conversion factors. If you don't understand digital crop factors and can't read basic specs, you either need to hold your money or find a dealer that you can trust to explain it to you. But the manufacturer shouldn't be accused of making a bad product because you don't understand the specs.
A previous user gives a poor rating because he either didn't read or understand the lens specifications. The rating was retain while most of the review was deleted because it simply didn't make sense. If you tried to use a 8x10 wide angle lens on a digital slr camera, you'd end up with a super telephoto because you're only using a portion of the image circle. Someone who calls this lens worthless because he bought first and thought later is blaming Sigma for his lack of attention to the laws of optics and of physics.
When you buy lenses for digital cameras, you have to take your brains out of your boots. This is a fisheye lens that's excellent on digital cameras, You get the full fisheye effect on a full frame digital camera --- OR at full 35 mm. You don't get the same effect on most DSLRS. When Panasonic Lumix claims 28mm lens width in its new line, it's not serious, but is referring to the apparent focal length when compared to 35mm film.
The lens can be used on cameras like the 20D or 30D which have a 1.6x crop factor. The news high speed top End EOS 1D Mark III will also have a crop factor of 1.3 while the 1ds and 5D are both full frame and will take full advantage of the 180 degree (on the diagonal) that this lens and other fisheyes offer. This lens is very good close to the optical quality of the Canon fisheye -- I've used both. But the game here is the intentional distortion on full frame. A standard wide-angle of this focal length does not cover 180, but something around 112 degrees -- on full frame.
If you want an equivalent of the 16-35 used a 5D on your 30d, you need to buy the 10-22. Both are rectilinear, corrected for distortion. Even the high end 1D doesn't get flll benefit of the fisheye due to crop factor. There are optical gimmicks if you want the effect, but that's not appropriate here.
The build quality of this lens is very good, not quite up to the level of the top drawer (and expensive) L lenses, but it is equal to Canon lenses for about the same price. It's difficult to use filters on this lens-- it isn't designed for them and filters would be makeshift -- and that big front element is vulnerable as with all of the real fisheyes. There are a couple of quirks that take a little getting used to in the controls for a regular Canon user.But I find it a little tricky going back to Leicas after too much time away -- and their controls vary with product. The images are high quality and a reasonably skilled photographer can produce excellent work with this lens without relyin entirely on fisheye cliches.
Users of digital cameras with crop factors should consider the shortest focal length fisheye lenses, approx 8 millimenters which also producs a 180 degree image, but in a circle. While I don't get the circular image on the 20D that I do the 5D it does give a lot of the distortion and on the diagonal approaches 180 with the rectagular image. I haven't measure it and don't have a reason.
The Sigma in a custom mount might produce interesting circular images on medium format film or digital sensors, but that would involve a careful matching of the mount to focal plane location. It is usually a waste of money to buy high end full frame lenses in shorter focal lengths for smaller digital sensors. You're paying for a lot of glass designed to cover a larger frame.
22 de abril de 2007
If you are trying to use this product with a dslr like I was, dont expect to see distortion. For the price go with an 8mm fish.
12 de agosto de 2007
This lens is really incredible... The quality has always been great with Sigma and this lens is as great as Sigma's reputation...
If you plan to use this lens with a Digital Camera, do not forget that there is a x1.2 coefficient (this lens is a 15mm but used on a Digital Camera, it turns into a 18 or 20mm). If you want the effect of a fisheye (180degrees), consider buying a shorter lens (8mm).
The 15mm fisheye from Sigma is a great super wide angle if used on a digital camera...