Tamron 24-70 vc + 5diii users ?

Anyone get missed focus shots when using outer AF points?

I recently purchased this lens used from a group on facebook, received the lens and excitedly mounted to my 5diii. The first image a took using one of the upper right AF points (x type), and it was completely soft. In my confusion, I began taking more test shots and discovered that the lens would severely back focus if I attempted to use any of the outer AF points but was tack sharp only in the very center. Seeing how I rarely take a shot using the center AF point, I attempted to MFA the issue away. I was at -20 and was still missing focus. I then called Tamron and found out the lens needed to be adjusted at the tune of $250 minimum. I went to our local camera store (2.5hr drive) and tested their display copy of the lens on my 5diii to find the it to function the exact same way. The store salesman and I mounted the store copy on their 5diii and again had the same results. I then tested the new Canon 24-70 ii on my body and obtained tack sharp photos from every AF point I tried.

here is an image with the upper right AF point in use. subject was the SB700 flash diffuser package text. you can clearly see the severe back focus

Here is one with the center point used on the same packaging

My first thought is that maybe this is the reason the lens was sold. If it were under warrantee, I'd just send it in to Tamron as they claim to know the problem and how to repair it.

You could try and focus in Live view, that will most likely give better results. I am thinking that the field curvature of the lens is quite high so that the field of sharp focus is behind where the camera thinks it is for the outer AF points but in the center it's accurate.

You could try and focus on a flat subject using the outer AF points and see if the photo is sharp anywhere.

https://photography-on-the.net …/showthread.php​?t=1274691

From this forum, back in 2013. It appears it's a common issue with the lens. Maybe your copy is from 2013?
If it's common, was there maybe a recall?

When I called Tamron on the issue, they were not going to repair free of charge. So I don't think there is a recall

The warranty in the US is 6 years - http://www.tamron-usa.com/lenses/warrant​y.php

That's why grey market Tamron 24-70 go for $900 and from authorized reseller $1,300 (last time I checked).

I just put this lens through its paces during a recent trip to Valley of Fire State Park (NV), and then a senior shoot. I used a lot of different AF points with my 5DIII and didn't really notice any images being badly OoF. BUT it hunted quite a bit, even in good light. Very irritating, especially when shooting people. Overall though, happy with the sharpness.

It seems that i forgot to update this thread with the fact that i went back to Robert's camera in downtown Indy and had them grab a new out of the box lens for me and it worked nearly perfect on my 5diii. I have no idea what the issue was with the other copies. Im assuming a firmware update. Just happy that i found one that works... Also bought the Tamron 15-30 vc. Loving them both

amish wrote in post #17506894
It seems that i forgot to update this thread with the fact that i went back to Robert's camera in downtown Indy and had them grab a new out of the box lens for me and it worked nearly perfect on my 5diii. I have no idea what the issue was with the other copies. Im assuming a firmware update. Just happy that i found one that works... Also bought the Tamron 15-30 vc. Loving them both

ugh... my 15-30 is backordered... wth... i want one now

Yeah it was a total fluke that I ended up with one Talley. I had to drive back 2hrs to return a defective Tokina 16-28 that I had purchased 2 earlier and the sales guy pulled this one from the back. Said they had just got it in that day+. I already knew I was going to buy it before I mounted it to my body for test shots.

amish wrote in post #17507640
Yeah it was a total fluke that I ended up with one Talley. I had to drive back 2hrs to return a defective Tokina 16-28 that I had purchased 2 earlier and the sales guy pulled this one from the back. Said they had just got it in that day+. I already knew I was going to buy it before I mounted it to my body for test shots.

U suck

I returned my copy of this lens for lack of sharpness (perhaps due to bad focusing) and purchased the Canon version. Best decision ever as my keeper rate is almost 100%.

Talley wrote in post #17507734
U suck

Sorry Talley... wasnt trying to rub it in..... ok maybe a little

I tested the store copy of the Canon mkii... it was amazing and I was ready to pull the trigger before i discovered that there were some good copies of the Tamron. I would have been happy either way. I may end up with the canon at some point.

How big have the issues with the Tamron AF been overall?