R7 Autofocus Hunting Issue with Tamron 18-400mm Lens

[sonoma]

I've been having consistent autofocus issues trying to use my R7 with the Tamron 18-400mm lens using the control ring EF-EOS to R mount adapter.  The lens will often work fine for the first 5-10 minutes of a photo shoot, but then it will start hunting for focus and be unable to focus on anything.  Turning the power off and back on doesn't help.  The firmware on both the camera and lens have been updated to the latest versions.  I shipped the lens to Tamron for troubleshooting and repair, and they adjusted the autofocus, but that hasn't resolved the problem.  The lens works fine on my older Rebel T4i that has the same EF-S mount as the Tamron lens so no adapter is needed.  Is it possible that the mount adapter is defective?  Or does the R7 with the mount adapter just not work properly with the Tamron lens?  According to Tamron, the R7 is supported with this lens.

[sonoma]

Hi Trevor,

Thanks for your reply.  Tamron has a lens/camera compatibility page at https://www.tamron.com/global/consumer/support/checker/ that specifically says that the 18-400mm lens is compatible with the R7.  I checked that before I purchased the lens.

I am mostly using single shot mode with the lens, not high-speed shooting, so max frame rate or full buffer should not be any issue.  My problem is with inability to focus to take an initial shot, not incorrect focus on multiple shots.  The lens fails to focus on anything so I get the red focus indicators instead of green and the image in the viewfinder is completely blurry with nothing in focus at all.  So I think what I'm seeing is quite different from the issues that you're describing or what is mentioned in the video by Duade Paton.

[cranfordrd]

I have the exact same issue with my R10, I have the adapter with the control ring and just read that the adapter is the issue, so I am returning this adapter and getting the one without the control ring. Hopefully that will fix the issue!

[March411]

There is a firmware update specific to the R7 cranfordrd. Are you running the current version?

Tamron 18-400mm Firmware for R7 Dec 14, 22 

Tamron Compatible lens chart  Last Update Date October 24 2024

 

[cranfordrd]

I asked at the camera shop and they tried but didn't have some kind of item they needed to update the firmware. Do you know how I can get the firmware updated?

[sonoma]

I installed this firmware but it made no difference; I still had the same focus problems.  The Tamron TAP-in Console is needed to update firmware in the lens.

[March411]

My experience with Tamron is somewhat limited so hopefully others will jump in to assist. I do know that you will need to use the TAMRON TAP-in Console or the TAMRON Lens Utility software  

Also compatibility with R7: R7 compatibility to Tamron Lenses 

Use the links above to do some research, there are also links to download the Utility Software. Hopefully ebiggs1 will drop by as I believe he has more knowledge with Tamron and may be able to assist.

[Waddizzle]

This is a lens issue.  Canon doesn’t guarantee that third party gear is compatible.  Those claims are made by others and supported by others.  

Many third party lenses seem to work well with the R7, including most lenses made by Tamron.  

[March411]

The only goal I have, attempting to try/help get the challenge resolved for the members that have the lens. So if the TAMRON TAP-in Console is required and you really want to find out if it is a firmware issue. KEH has a used, like new one with caps for $39 and MPB has one in excellent condition for $27 now you just need to decide if you want to make the investment.

I use Sigma and have the dock, all my lenses performed perfectly when I went to R bodies but only after I did the firmware updates. Like I said, I don't have as much knowledge to offer on Tamron.

[cranfordrd]

Appreciate your info and advice! At this point I am going to return the adapter with ring and get the plain one to see if that helps.

[ctitanic]

I had the same issue with R7 and Tamron lenses. Like Trevor already explained the R7 is a very "peaky" camera when it comes to lenses and AF. I opted to only buy lenses that somebody already tested in the R7 and posted about being fully compatible. Real life tests. I recall that there was somebody keeping a compatibility list with all those real life reports but since I sold my R7 I did keep that bookmark any more.