Environmental Sealing & Protection? Yes - sealed to keep dust and moisture out AND with a fluorine coating on the front element to repel dust and dirt. With the use of the optional Sigma APO teleconverters, this lens can be used as a 420mm F4 AF ultra-telephoto lens with a 1.4X EX teleconverter, or a 600mm F5.6 AF ultra-telephoto lens with a 2X teleconverter.

Does suffer from CAs & purple fringing. You can see it in the sun's reflection in the eye of the Dik-Dik below at the very end (last image)... and some bird shots into a gray cloudy sky shows it in the tree branches. Sigma notes when Digital Lens Optimizer, located within the EOS R settings menu, is switched to 'OFF' but peripheral illumination correction, chromatic aberration correction and distortion correction are turned on, those corrections will be made for each lens, specific to their optical characteristics. 'This is applicable to DG and DC lenses from Contemporary, Art and Sports line listed below which were released after March, 2018, or those of which firmware has been updated to Ver.2.0 or later,' says Sigma in the press release. Here's a few of the more easily missed or overlooked specs that may be important to some photographers. Lens weight and size dimensions are in a separate section below. While the wide-open performance of the Sigma seems to be worse, the Sigma 2x actually performs better than the TC-20E III when stopped down in the center. Mid-frame and corners are weaker, but the center resolution is higher! Summary The Sigma 120-300mm f/2.8 EX DG HSM Lens is available in Canon (reviewed), Nikon (D) and Sigma mounts.a resolution/image quality reducing cropping step during post-processing - A big advantage for this Sigma. The astonishing invention of the 300/2.8 by Topcon in 1958 is arguably the birth of the supertelephoto lens concept (i.e. long focal length with very wide aperture). It's a landmark in photographic lens history. Like I pointed out above, forget about trying to get this teleconverter to focus on Nikkor lenses. On Sigma lenses, however, it is a different story. Although the AF speed and accuracy decreased a little, the combo worked even in low light situations. I was able to focus with the 120-300mm + Sigma 2x TC on the D3s in my living room that was lit with just a single 100 Watt light bulb! There were a couple of focus errors here and there, but it worked out quite well overall. On the negative note, the AF reliability seems to go down at distant subjects (towards infinity). NIKON D7100 @ 600mm, ISO 800, 1/500, f/5.6 Sharpness, Contrast and Color Rendition This 120-300mm lens sees the same angles-of-view on full-frame as an 80-200mm sees on DX. Used on a DX camera, this lens sees the same angle-of-view as a 180-450mm lens sees on FX (see crop factor). VR Controls? Like with all recent super-telephoto primes and zooms it has a 3-position button for the various VR modes - OFF, VR Normal, VR Sport. Those shooters who like to shoot in bursts should be happy that the VR Sport mode hasn't gone away...

I shot this test on three different occasions (a very time-consuming process) - each including many samples shot using AF, Sports and Wildlife photographers would love this lens. The best thing is, I did not care about the weight after a while. It was fun to shoot with. Please Support The PhoblographerSAN DIEGO, CA – Jan. 17, 2023 – Today, Sony Electronics announced the development of the long-awaited full-frame E-mount 300mm F2.8 G Master OSS Telephoto Lens, with a target launch date in early 2024. And of course, the non-IS Canon EF 70-200mm f/2.8 L USM Lens is a very close alternative that costs far less than the IS version.