Tamron 24-70 VC not sharp on 70 mm setting

Hello, bought Tamron 24-70 VC to replace 24-70 2.8L and 24-105 4L IS. But found that 70 mm setting is very very unsharp ... Returned to shop tried + 2 lenses, all of them were very weak on 70 mm. Even closing apertures won't helped. Images are blurry.

I don't know why everyone compares it to 24-70 2.8L II, but Tamron even stand close to 24-70 2.8L I ... Yes on 24 mm Tamron is sharper, but 70 mm is the FL where I use it alot.

Below are few samples of corners (center is a bit better, but not so much). Tried it on 5D3 and 6D, results are same.

Shop says there is two more other Tamron lenses. How do I need to check them before exchange one to other?

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I'd say I have a decent copy. I'll check my corners though and report back.

If your center is not like this then you need to get it checked out.

Tamron 24-70/2.8 is known to be softer at 70/2.8 than the brick canon 24-70/2.8 I.

I checked it many times and for me it is important to have it sharper at 70 than at 24. Cuz 24 I usually step down a bit.

When Sigma Art equivalent is released, it will kick Tamron's ass.

martincappi wrote in post #16820157
Tamron 24-70/2.8 is known to be softer at 70/2.8 than the brick canon 24-70/2.8 I.

I checked it many times and for me it is important to have it sharper at 70 than at 24. Cuz 24 I usually step down a bit.

When Sigma Art equivalent is released, it will kick Tamron's ass.

I like Tamron and what they've been doing for quite a while...but you're probably dead on right about the impending Sigma equivalent. It will probably be just as sharp as the Canon II, have OS, and cost less.