Sigma 24mm f1.8 EX DG Aspherical Macro is one of the EX Series lenses. This lens has a fast F1.8 maximum aperture with macro focusing capability of minimum focusing down to 18cm/7.1inches (reproduction ratio 1:2.7). The iris diaphragm has 9 diaphragm blades to obtain beautiful out of focus image. It incorporates the floating focus system and uses two aspherical lens elements for minimizing distortion and spherical aberration and astigmatism. Internal focus system eliminates front lens rotation, thus allowing the use of a Perfect Hood and the easy use of polarizing filters. The lens incorporates non-vignetting optical construction, in order to obtain adequate peripheral brightness even at open aperture. This is desirable for digital cameras. The lens also incorporates dual-focus mechanism. It is easy to hold the lens, since focusing ring does not rotate during auto-focus, and yet it provides adequate focusing torque of the focusing ring during manual focusing of the lens. The lens materials used in this lens are lead and arsenic free ecological glass.
This review was made on a full-frame Nikon D700. Situation may be different on cropped bodies. Pros: 1. Ability to focus very, very close 2. Bright, shallow DOF (f/1.8) 3. Aperture ring, in case you want to use it on a different camera, with an adapter. 4. Warm colors 5. Sharp in the center wide-open Cons: 1. Corners and border image quality wide open is non-existent. They almost blend with OOF areas. Apart from center nothing is sharp wide-open. 2. My sample had a centering defect, having worse image on one side of the frame compared to the other. 3. Field curvature, although it is common for super-wide angle lenses 4. High chromatic aberrations, especially wide open 5. Light sources create ghosting effect when shooting wide open, probably due to coma. 6. It gets very sharp, unfortunately only at f/8. 7. Size & weight for the image quality it delivers. If you want something else than close-ups wide open, you will be better off with a fixed lens from Nikon (24mm f/2,8) which is miles lighter, significantly smaller and probably cheaper. I have returned my sample. I would not recommend this to anyone without carefully testing it first. This however may be your best choice for close-ups with a wide angle as long as you keep your subject close to the center in order to get sharp results.
I have tried this lens on a full-frame body. This can be a very nice lens for macro work (although magnification can be an issue) provided you keep the subject more or less in the center of the image. It may be good in low light but also keep your subject in the center. Pros: 1. Very small working distance, can create some unique perspectives 2. The lens seems to be optimized for close focusing distance 3. Nice warm colors 4. Aperture ring 5. Autofocus Cons: 1. Border performance almost inexistent, it is unacceptable. 2. Coma is badly corrected, I get blobs of light at the image border coming from silver-like reflecting surfaces. 3. My sample had a centering issue, as the left side of the image was of lesser quality than the right part. 4. Border doesn't sharpen up until f/5.6, f/8 5. Chromatic aberations I would not recommend this lens unless you use it exclusively for its macro abilities. Otherwise save your money.
Although this lens is much cheaper than the equivalent Nikkor AFS 24 f/1.4 it's a tremendous bargain based on the cost of the $1999.00 Nikon with a cost savings of $1450.00! It delivers amazing images, sharp and contrasty especially with a good cicular polarizer. The best part is the amazing 1:2.3 macro or close focusing ability of this lens. Wide angle macro's are simply a lot of fun and adds a different perspective to wide angle photograhy.
this a good lens for the price , i consider it entry level ,if you have the money get the cannon lens .
Close and wide is fun
This lens I sent back. Give bad reading on monitor EE on camera monitor.
I bought this lens and I have been using it on a aps-c sized camera and I absolutely love it! I have been putting it through a lot of test and the only flaw I can see would be the slower AF. I am using it mostly on a tripod for macro or landscapes so Image Stabilization isn't needed! Overall Very happy with it!
In comparing this lens to the Canon 24mm 1.4 L, I was very surprised. My copy had no forward or back focusing issues. A bit soft wide open; however, very nice at f 2.8 and higher. A quieter focus motor would have been great, small sacrifice for such great images. Beautiful creamy bokeh...Here is what not so great: The filter that came with the package does not have a thread to support the Sigma cap, it fall of. [...]
This lens is a great fixed lens. It makes you get more creative since it's not a zoom. I am very pleased with the images I get with this lens!
My sample was not focusing correctly on Nikon AF bodies (F5, D300). Focus was just really off. It is very built, heavy, metal. On an FM2, the manual focus allowed for relatively sharp pictures at f1.8. Not amazing, but OK for price paid. I returned mine and do not know if will try another anytime soon.