Canon EOS R7 with EF-RF Adapter Problems

[Rhajeem]

I'm having some issues with both the official Canon EF-RF adapter and 3rd party adapter (Viltrox EF-RF) with older lenses such as the Tamron SP 17-50mm f2.8 VC version when shooting video. I noticed that there's a 'jump' or 'shift' when it focuses but only while recording. Perfectly fine when taking photos or while not recording. Happens even when I manually focus and even with Vibration Control turned off. I have an EOS R as well and the issue is not present when I use that lens paired with the official adapter or 3rd party. Bought another Tamron 17-50mm to see if this was an isolated issue but both lenses were displaying the same problem. Wanted to know if anyone else had issues when recording using these older EF lenses paired with the R7. I will attach a video of the problem I am facing as I am unable to use this lens with my R7 for video. All my other lens work perfectly fine with both adapters however.

Video:

Canon R7 and EF to RF Adapter Issue 

[Waddizzle · Accepted solution]

Welcome to the Forums.  There was a recent thread related to the question of compatibility of Tamron lenses with the R6 Mark II, which uses the new Dual Pixel AF II image sensor technology.

Just to be clear.  The Viltrox adapter is not fully compatible with the Canon RF mount.  It never has been, which is probably one reason why Canon made them stop producing it.  Users were blaming Canon for its flaws.

You are not having issues with the Canon mount adapter or Canon EF lenses.  You’re experiencing issues with a third party lens that was not designed for MILC bodies or the Dual Pixel AF II sensors.  

The incompatibilities become most acute in the video modes.  This was pointed out on the recent thread that I mentioned.  Using One Shot AF does not seem to be an issue.  Tracking moving subjects with the any of the Servo AF modes seems to be a problem.

[EDIT] With the release of camera bodies using the new Dual Pixel AF II sensors, Canon has released firmware updates to several of their RF lenses.  

[Rhajeem]

Thank you for this information. You're right, when I turn off Movie Servo AF the issue doesn't happen with this lens. I guess this means I'd just keep this for more of my photo work and get a more modern lens for video, maybe the Sigma 18-35 1.8.

[Waddizzle]

If you wish to capture video with Movie Servo AF,  then I recommend against using a third party lens.  Not every lens that is great shooting stills is great for shooting video, especially when it comes to Movie Servo AF.  

Not even every Canon EF mount lens is fully compatible with Movie Servo AF and Dual Pixel AF sensors.  As a general rule for EF mount lenses, you want Canon EF lenses that have initial release dates from 2009 or later, which is when DPAF was first introduced. 

Use one of the Canon lenses that are listed towards the end of the R5 and R6 Advanced User Guides.  The lenses are listed compatible with high frame rate, 12 fps, shooting.  I do not know why this info was omitted from the R7 Advanced User Guide.