Opticallimits

https://photozone.smugmug.com/Sigma-100-400mm-f5-63-DG-HSM-OS-Contemporary/

Not too shabby - for the price. I was surprised by it a year ago as I didn't realize Sigma made this thing.

But Tamron also makes such a thing, and the big question appears "which to buy?" Even though I own a couple of Sigma Art primes, in the long range Tamron does a couple of things better - not necessarily optical, but usage:


100-400:

• Tamron offers a (pricey) collar, but it comes with inbuilt Arca-type foot and fits perfect on the metal part of the lens barrel
  
• Focus limiter - best system I know: depending on the distance, the limited area is in front or behind a chosen and adjustable (tap-in console) limit distance OR an also adjustable fixed focus range.
  
• lens hood is easier to attach, I'd say
  
• No problem to hand hold, but that goes as well for the Sigma. VC is excellent.
  
• rubber gasket around the mount (Sigma's contemporaries don't have that feature) Don' know if it's only cosmetics or indicates better sealing.
  

150-600

• Tamron (VII) has the second best tripod foot right in the package. Sigma has a better one for the Sports, but adds extra 200,- to the bill (and to the weight as well)
  
• zoom brake at any position (Tamron VII), Sigma Sports at some positions, Contemporary without.
  
• lens hood of Tamron less complicated to put on than Sigma Sports, Contemporary I don't know.
  

I also tried Tamrons 85/1.8, but that falls short to the 85/1.4 Art. But as of now, for tele-zooms I'd look first into Tamron.



Tamron 100-400, 400 mm cropped, f/9, D850