Sony announces trio of ultra-light, ultra-compact fast G-series primes: 24mm F2.8, 40mm F2.5, 50mm F2.5


posted Tuesday, March 23, 2021 at 9:00 AM EST


Just a week after Sony unveiled its super-fast FE 50mm f/1.2 GM lens, they now have some more optical goodies to announce -- three, in fact. The new FE 24mm f/2.8, FE 40mm f/2.5 and FE 50mm f/2.5 make up what Sony is dubbing the G-Lens Ultra-Compact Primes. Though sold individually, this trio of lenses all sport identical exterior designs and the same overall physical dimensions, with the only differentiation being each lens' unique optical design for its particular focal length. They also all come at the same price point of $599 USD.

The compact and lightweight design of the new G-series primes make a perfect pairing with the equally-compact Sony A7C.

With these three G-series prime lenses, Sony's following a similar approach to other lens manufacturers, such as Sigma and Tamron, in producing a family of relatively-fast mirrorless prime lenses that all use similar a design and styling, are focused around compactness and light weight, and that have budget-friendly price points. Last December, Sigma announced three additions to its "I Series" of ultra-compact mirrorless primes, which includes 24mm, 35mm, 45mm and 65mm varieties. And Tamron, meanwhile, has an affordable prime set of their own, with 20mm, 24mm and 35mm flavors. Needless to say, but if you're a Sony E-mount owner in need of one or more lightweight, affordable and relatively bright prime lenses, there are numerous options to consider.

The FE 50mm f/2.5 G shown here, along with 24mm and 40mm prime, can easily fit in the palm of your hand.

As mentioned, these new Sony G-Lens Ultra-Compact Primes all share an identical exterior design, with the only visual differences being the engraved markings of the focal length and aperture on the side and the printed labeling on the front. In terms of physical measurements, the lenses are all 45mm (1.77 in) in length and 68mm (2.68 in) in diameter. The weights are all ever-so-slightly different due to the variations in optical design, but they are all extremely similar overall; the 24mm weighs in a 162g (5.8 oz), the 40mm at 173g (6.2 oz) and the 50mm at 174g (6.2 oz). All three lenses include 49mm screw-on filter threads. 

The new Sony G primes all share the same overall physical size and design.
The Sony FE 24mm f/2.8 G paired with the compact Sony A7C.

Despite the ultra-compact form factor and wallet-friendly price, these Sony G-series primes are impressively spec'd and feature-rich as well as built with quality materials, including an all-aluminum exterior, metal lens mount and a weather-sealed construction (with a rubber gasket around the mount). All three lenses also offer several exterior amenities, such as a customizable Focus Hold button, AF/MF switch and a dedicated aperture control ring with a de-clickable toggle switch much like Sony's G Master lenses.

The new Sony G Lens Ultra-Compact Primes all feature a focus ring, a manual aperture ring, customizable Focus Hold button and an AF/MF switch, as well as an aperture ring "de-click" toggle button (on the other side of lens) 

The aperture ring, while small and fairly thin, is raised and has a deeply ridged surface for a pleasing tactile feel and easy operation. The ring is marked at all full-stop and third-stop apertures and includes an "A" setting for those who want to control the aperture setting via the camera. In use with the "clicked" setting, the aperture ring has a fairly stiff feel to it, with nice and solid clicks between aperture stops; it doesn't feel easy to accidentally move the aperture ring. In the de-clicked setting, the aperture ring on all three lenses rotates very smoothly, but also maintains a pleasing amount of rotational resistance so as to avoid accidental aperture changes.

A7C + FE 50mm F2.5: 50mm, f/2.5, 1/2500, ISO 100
(Click for full-resolution)
A7C + FE 24mm F2.8: 24mm, f/2.8, 1/2000, ISO 100
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The focus ring on these lenses sits right at the front edge of the lens. While small, the focus rings has a very smooth rotational feel, and with its "Linear Response MF" design, the lenses offer responsive and precise manual focus control -- despite the inherent focus-by-wire design of these mirrorless lenses.

A7C + FE 40mm F2.5: 40mm, f/2.5, 1/1600, ISO 100
(Click for full-resolution)
A7C + FE 24mm F2.8: 24mm, f/2.8, 1/800, ISO 100, -0.3EV
(Click for full-resolution)

Under the hood, the optical layout of each of these three G-series lenses varies in order to create different focal lengths. The optical layout of each lens is as follows:

  • FE 24mm f/2.8 G: 8 elements in 7 groups, including 1 ED (extra-low dispersion) glass element and three aspherical elements
  • FE 40mm f/2.5 G: 9 elements in 9 groups, including three aspherical elements
  • FE 50mm f/2.5 G: 9 elements in 9 groups, including 1 ED (extra-low dispersion) glass element and two aspherical elements

The use of aspherical elements in these lenses helps combat aberrations and ensure high-resolution image quality, and the inclusion of ED glass further helps suppress chromatic aberrations and color fringing. Additionally, the three lenses use a 7-bladed circular aperture diaphragm for natural and smooth bokeh.

A7C + FE 40mm F2.5: 40mm, f/2.5, 1/1600, ISO 100
(Click for full-resolution)

In terms of autofocusing, the lenses incorporate dual linear motors to drive the lightweight focusing element(s), which allows for both fast and precise AF performance as well as quiet focusing during video recording. They do not use the same "XD Linear" motors as in some of Sony high-end G Master lenses, however, but the focusing motors are nevertheless similar. According to Sony, the focusing element/group in these compact primes are so small and light that they do not need the higher thrust afforded by the XD Linear motors.

Minimum focusing distance varies slightly between each lens and also differs depending on whether you use autofocus or manual focus; you can focus slightly closer using manual focus. The 24mm lens focuses down to 0.18m with MF or 0.24m with AF for a 0.19x magnification factor or 0.13x mag. factor, respectively. For the 40mm lens, minimum focusing is slightly longer at 0.25m (MF) or 0.28m (AF) with 0.24x (MF) and 0.20x (AF), while the 50mm lens is longer still at 0.31m (MF) and 0.35m (AF) for 0.21x (MF) and 0.18x (AF) magnification factors.

A7C + FE 50mm F2.5: 50mm, f/2.5, 1/2500, ISO 100
(Click for full-resolution)

Pricing and Availability

All three of the Sony G-Lens Ultra-Compact Primes are set to go on sale in May 2021. The 24mm and 40mm primes are slated to go on sale on May 13th, with the 50mm following a couple of weeks later on May 27th. All three will be sold for an estimated retail price of $599 USD or $799 CAD.

To browse more full-resolution images, jump over to our Sony A7C Gallery Page. Search for images with "SonyPrimes" in the filename.

Sony A7C Gallery