Differences between EF-RF adapters by Canon, K&F, and Meike

[ochia03]

I am looking at getting an EF-RF adapter for my new R50. What is the difference between the 179CAD Canon adapter, or the 64 CAD K&F concept adapter or the 72CAD Meike adapter? Is there any reason I should spend so much more on the canon first party verion?

[deebatman316]

No because the lens tells the camera that it’s designed for APS-C. 

[March411]

Hey @mleclerc7 ,

I run several adapted lenses on my R bodies and the meta data is accurate. Surprisingly my latest purchase the Laowa 100mm macro is even picked up correctly and displays in Canon DPP with no issues. I use only Canon adapters, tested others and the results were poor. 

[mleclerc7]

I just received the Canon-brand adapter and sadly the issue persists.

In Av Mode I have the option to set Cropping/aspect Ration to 1.6, to match my Tamron zoom. (Panel 1-1 on the menu, second item from the top) 

In Scene or A+ modes, I do not have that option, and the image is not cropped. The Tamron Lens is EF (Model B003) and the RP switches to the proper crop ratio when I use the Canon 50mm 1.4  EF lens.

Am I missing something ? Is my Tamron  just too old ?

Any insight appreciated !

Image not cropped in A+ mode using the Tamron EF zoom

[jrhoffman75]

I suspect the problem is that it is a third party lens. In the “ beginner “ modes many options are disabled. 

[March411]

Hey @mleclerc7 exactly which lens is giving you challenges, please give the full name.

Have you checked to see if the firmware can be updated or is it to old?

[mleclerc7]

Hi John. The lens name is  Tamron AF18-270mm F/3.5-6.3 Di II VC LD Aspherical [IF] MACRO. It is a discontinued model from 2011. The model number is B003E. Here the link the the amazon description. (not where I bought it. Just for the details provided): Tamron AF 18-270mm f/3.5-6.3 Di II VC LD Aspherical IF Macro Zoom Lens for Canon Digital SLR Cameras...

[jrhoffman75]

Only Canon lenses use the EF-S mount. Third party lenses, even though they may only be "sized" for APS-C, use the EF mount.

It is the EF-S mount on the adapter that triggers the crop mode. It needs to be manually set for third-party EF APS-C design lenses. The A+ mode doesn't allow access to many menu options, like the selection of the crop mode.

Creative Mode menu:

Basic mode menu

[mleclerc7]

Thank you for the clear and complete answer. Now I know where I stand.

[ebiggs1]

WOW! A 15:1 zoom ratio. I was not even a lens.