The Sigma 24mm F3.5 DG DN is part of a new series of compact, high-quality and affordable fixed focal points.

The Sigma 24mm F3.5 DG DN is a lens in a new series of Sigma fixed-focal length lenses. Sigma calls it the I series, and the other lenses in this series are the Sigma 35mm F2.0 DG DN and the Sigma 65mm F2.0 DG DN. They are lenses in the Contemporary series. So they’re not Art lenses. Nevertheless, the lenses are designed to give the highest image quality, they have a metal housing, and they are weatherproof. On this point, they are hardly inferior to lenses from the Art series.

In addition to image quality and robustness, the user interface is also important to Sigma. The ribbed focusing ring, which we now also know from the Sigma 45mm F2.8 DG DN, is part of this. It gives a lot of grip. The I-series lenses also have an equally strongly serrated aperture ring. The use of the aperture ring is optional. If you set it to A, you can set the aperture on the camera. A funny innovation is the magnetic lens cap, which is easy to put on the lens.

Check out the introduction of Sigma’s new I lenses above, starting at 19:55.

The Sigma 24mm F3.5 DG DN is the most wide-angle lens in the I series. It is also the least bright lens. Brightness is slightly less important for a wide angle than for lenses with a longer focal length. The shortest usable shutter speeds are already longer because of the short focal length, bokeh is often less important, and for many applications such as landscape, interior and architectural photography, more rather than less depth of field is needed. Nevertheless, F3.5 is not very bright. On the other hand, the Sigma 24mm F3.5 DG DN is fairly compact and light, and you can focus very close with this lens, to a magnification of 1:2. The new I lenses are available in E mount and L mount. They can therefore be used on the mirrorless cameras from Sony, Leica, Panasonic and, of course, also on Sigma’s FP.

BUILD

The Sigma 24mm F3.5 DG DN is a robustly built lens that has an all-metal housing. The serrated focus ring and aperture ring are therefore also made of metal and not rubber. The lens is also weather-resistant. The optical design consists of 10 elements in 8 groups. To minimize chromatic aberrations, one of the lens elements is made of special SLD glass. The lens also contains no fewer than three aspherical elements. The diaphragm has 7 rounded blades. The filter size is 55 mm. This is different from the 58mm of the Sigma 35mm F2 DG DN and the 62mm of the Sigma 65mm F2 DG DN. Unfortunately, this means that you need a different filter size for each lens.

This lens has an aperture ring. Strictly speaking, this is not necessary for many photo applications, unless you use a camera like the Sony A7C that does not have a front dial or you want to operate an aperture ring with your left hand in the old-fashioned way. It gives the lens a nice retro look. However, it does not have a switch to make the aperture clickless for video applications, as the Sigma 105mm F2.8 Macro Art does. The lens has an AF/MF switch that you don’t, as usual, slide back and forth but that moves with the curvature of the lens. A funny innovation is the metal lens cap. It’s magnetic and therefore clicks very smoothly onto the lens. To store the lens cap when the lens is in use, Sigma supplies a lens cap holder that you can hang on your pants or bag with a carabiner and that you can put the lens cap on.

FOCUSING

Just like the 65mm and 35 mm, the Sigma 24mm F3.5 DG DN uses an STM motor for focusing. This is a stepper motor. It ensures accurate and silent focus. These types of motors are great for video. However, this type is not as fast as more advanced, newer solutions. The drive is optimized for both the Sony cameras, which use phase detection AF, and the Panasonic cameras, which only use a contrast detection AF system. The shortest setting distance is 10.8 cm. This results in a magnification scale of 1:2. 

IMAGE QUALITY

The MTF curves of the new I-series lenses look promising.

We will soon receive a copy of the Sigma 24mm F3.5 DG DN in our test lab, and then we will publish a full review.

CONCLUSION: REVIEW SIGMA 24MM F3.5 DG DN ON SONY A7R III