no, you made a ridiculous claim that there was a "better deal", and you once again failed to prove it... you know better. It’s been three-and-a-half years since that interview and in that time, Sony has continued to add new and improved technologies to its lenses. So it’s likely safe to assume the 300mm F2.8 will offer most everything Sony has on the technological front. Now here is a point to consider. Sigma are revamping their already new 120-300f2.8 OS lens. Their new lens will be out in 2013. They have improved the electronics of the 120- 300f2.8 OS which for some proved unreliable. Unlike the Sigma prime it will have optical stabilastion and a focus limiter switch. Furthermore you can, if my understanding is correct, adjust/customise the amount of disance limitation you wish to use and that being the case can be a very nice option...for me a dream come true! I do not think the optics have been improved but having said that the optics are pretty good and sharper than the the Sigma 300f2.8 prime. I requested a shop to to go out and take some images for me and send them full sized. I was very impressed, even with the use of a Canon 2X converter the images were sharp using a 7D. In the circumstances provided Sigma improve the reliability (and I think they will) the new 120-300f2.8 will be an excellent birding lens offering so much more in terms of composition with the zoom facility. Is your mind able to grasp the concept of generation? I had high hopes but I am starting to get worried…

Sigma 120-300mm F2.8 DG OS HSM S Review - Photography Blog Sigma 120-300mm F2.8 DG OS HSM S Review - Photography Blog

great portrait lens in short-medium distance (up to 10 meters) - sharp from f2.8, great colours and bokehDetailed specifications for the teleconverter can be found in our lens database. Lens Compatibility

Sigma 300mm f2.8 EX APO HSM | BirdForum Sigma 300mm f2.8 EX APO HSM | BirdForum

like how they only used four screws to attach the z-mount lens mount to the camera body, while the other brands used five or six screws? There isn't much in the way of control features on the lens other than the aperture and focus rings; a single switch allows the user to deactive autofocus control on the lens. A recessed and windowed distance scale is provided, with markings in feet and meters, however there are no depth-of-field markings; neither is there an infrared index. The lens aperture is composed of 9 diaphragm blades, which should serve to produce pleasing bokeh. In ultra-low light, the lens focus hunted a lot. You can’t use the cameras focus assist due to the distance. I do believe a flashlight with a little reach would help. Manually focusing with the lens was not an issue either. Ease of Use The optical performance of the 120-300mm f2.8 is indeed totally outstanding, but that just reflects the overall quality of Nikon optics and says nothing about what generation this lens belongs to.Lens construction - 11 elements in 9 groups, including two Extraordinary Low Dispersion glass elements (Abbe number 90.3) stop matters a lot. 100-400mm is too dark with 1.4x TC. With the 400mm f4.5 I still have a very usable 560mm f6.3 which is also much lighter and smaller than my massive 200-600mm. Also z400mm is lighter than Sony 100-400mm, also sharper too especially with 1.4x and 2x TCs. Its not nearly the same weight at all. About 300g or 20% lighter is not "nearly same weight".

Sigma 300mm F2.8 APO EX DG HSM User Reviews: Digital

Nikon's F-mount underwent several iterations with limited inter-compatibility. Pre-Ai, Ai, AF, AF-D, AF-I, AF-S, AF-P. And now, the entirely different Z mount. Nothing prior to AF-S can autofocus on their mirrorless cameras even with an adapter. You need to do pushups to get comfortable hand holding this lens for long periods. It has some weight to it. Corner shading isn't much to write home about when the lens is mounted on the sub-frame 20D - the corners are just a quarter-stop darker than the center when used wide open at ƒ/2.8. Stop the lens down even to ƒ/4, and the shading goes away. The focus ring is the dominant feature of the lens. The ring is 1 1/2 inches wide, composed of soft rubber ribs which run lengthwise to the lens. The ring turns 180 degrees through its focus range, providing excellent tactile resistance for manual focusing operations: it's nicely cammed, and very smooth. There are soft stops at both ends of the focus spectrum to let you know you've reached the end, but the focus ring will still turn albeit with an increased resistance. The lens can focus past infinity. Trying to figure out a sweet spot for my sigam 2x converter used in conjunction with my sigma 150-500…

Sony Electronics Announces Development of New 300mm F2.8 G Master OSS Telephoto Full-Frame E-mount Lens, Targeting to Launch in Early 2024

Those DSLRs lenses focus incredibly fast on mirrorless bodies, at least on Nikon side but this isn’t relevant as all the agencies who moved to Sony were using Canon gear,

Sigma 120-300mm f/2.8 DG OS HSM S Lens Review - ePHOTOzine Sigma 120-300mm f/2.8 DG OS HSM S Lens Review - ePHOTOzine

Mike, PL is largely correct about viewing standards. Most photos are consumed on small screen mobile devices. First I am comparing against the Canon lenses. The Canon 300 II has no equal IMO. Rarely use the Sigma lens now.

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With a magnification ratio of just 0.13x and a close-focusing distance of 2.5 meters (over 8 feet), macro users should look elsewhere. The Z 400mm f4.5 is 1.25KG or 1.16kg without the tripod foot. That's incredibly light! Its also relatively affordable compared to any current 300mm f2.8 + 1.4x TC. With the lens mounted on the full-frame 5D, we see similar results, with an increase in the level of corner softness. Wide open at ƒ/2.8, we again see an average of around 2 blur units, just slightly better in the center and significantly softer in the corners - in this case, between 3-5 blur units. Stopping down doesn't do much to improve the corner softening, it just seems to move it around (our sample may be slightly de-centered). Central sharpness improves slightly, but by ƒ/5.6 you've reached the apex of what this lens can offer for sharpness (it's quite similar at ƒ/8) - a small region of sharpness in the center, 1-1.5 blur units, and escalating corner softness - between 2 and 4 blur units. Diffraction limiting sets in at ƒ/11, and again, it's still quite usable at ƒ/22. Fully stopped-down at ƒ/32, results are just as soft on full-frame as they are on sub-frame.