Tom Reichner Thank you for the thoughtful reply to my review. I'm traveling teaching and testing more gear right now and wanted to reply asap even though I'm using my phone to do so. Hopefully I'll have few autocorrect typos. Optical construction is 25 elements in 15 groups, including 4 FLD (Fluorite-type Low Dispersion) and 2 SLD (Super Low Dispersion). The front element is oil repellant and if we look into the front of the lens we can clearly see the rounded 9 bladed diaphragm. Focusing is internal, so the length does not vary. The lens does extend when zooming. With static subjects, all three lenses deliver fast and accurate focus, and I didn’t encounter any unwelcome behaviour or particular problem during my two weeks testing them. Lenses – Should have no marks on the elements andoptically clear. There may be light dust present that will not effect theimagery.

Manual focus for landscape is OK, but any TC used on cheap super tele like such lens just degrade the image too much. the Sony 100-400 would be a much better option if you consider IQ- AF performance combined. For L-Mount users, two dedicated teleconverters can be used with this lens - a 1.4x (TC-1411) and a 2x (TC-2011). The TC-1411 increases the lens’s reach up to 840mm and the TC-2011 up to 1200mm. Ease of Use A dust and splash resistant structure *1 that stops water drops or dust from getting If budget is not an issue, and you want peace of mind about getting the lens that delivers the best performance overall, the Sony is your answer. It’s larger, heavier, but is also flawless on all levels, and it is the only lens that can extend your reach further with teleconverters, offering more possibilities when you can’t get close to your subject (something that happens a lot with wildlife photography). Sigma WR Ceramic Protector Filter 95mm - stronger, thinner and lighter protection for the front element

Verdict

The lens was designed with image quality in the out-of-focus areas in mind as well, with attractive compression and beautiful bokeh for creating eye-catching images that can only be achieved with a long focal length. At the wide end of 150mm the lens has an impressive minimum focusing distance of 58cm. This is not a lens that you can hand-hold for very long at all, being much more at home mounted on a sturdy tripod or monopod. The Sigma 150-600mm F5-6.3 DG DN OS Sports is a versatile 4x super-telephoto zoom lens for Sony full-frame and APS-C mirrorless cameras. It offers an effective focal range of 225-900mm when used on an APS-C sensor camera. out of 3 test copies of the lens showed a strong deterioration of corner sharpness when the lens was used in portrait orientation. Make sure to get a good copy. But if you can live with those shortcomings, it saves at least a little in terms of heft and cost, rivals the Sigma in terms of sharpness, and its linear autofocus drive also feels significantly swifter. And video shooters will definitely prefer the Tamron if they want the least possible focus breathing, as it's a bit stronger for the 150-600mm.

As I read the article, I couldn't help but notice some similarities between your recent experience and my own. I also just bought a Sigma zoom. But it is a bit different - it's the 60-600mm.

The Sony 100-400GM is nice, but has the extending barrel, and heavier focus ring. The reproduction ratio is nice though; with the 1.4x TC, it gets down to 0.5x; macro range. The 150-600mm F5-6.3 DG DN OS | Sports combines the build quality that upholds the SIGMA Sports line standards with excellent operability, taking into account different shooting environments and modes of operation expected with an ultra-telephoto lens. The 150–600mm F5-6.3 DG DN OS | Sports is SIGMA Sports line’s first ultra-telephoto zoom lens, designed from the ground up specifically for full-frame mirrorless cameras. It offers outstanding levels of performance, functionality, and build quality required for ultra-telephoto shooting in the most demanding situations. The bad thing is with TC's is the LENS INFO is wrong so for lens correction to the image is very hard to do. Why not take a read of our blog post about this New Sigma 150-600mm f/5-6.3 DG DN OS Sports Lens with loads of image samples and 100% crops to ogle and a lot more info. What’s in the box