I just bought a a7rIV. It seems that I can not use my Tamron lense with the touch screen. It also seems that I can not use some of the focus areas with this lense. Am I missing some setting or dose it have to be a Sony lense to use these functions?

 

Thank you

Perhaps I should mention that the lens is a-mount and the camera i e-mount so I use the LA-EA4 adapter.

The LA-EA4-adapter uses its own autofocus module and doesn't use the sensor based AF-system of the A7Riv. You are therefore limited to the AF areas that the AF-module of the LA-EA4 supports. I guess it's also the reason you can't use touch-to-focus because this is related to the AF-points on the camera sensor. If you want full functionality, better try an LA-EA5.

Confirming what Pieter says, the LA-EA5 uses the camera's own full-function autofocus system. Whether it will work as you expect with a legacy non-Sony lens is another question -  I have got full functionality with my Tamron 150-600 G02 but Sony will only confirm full functionality for their own lenses. Before you purchase, can you get to a Sony dealer and ask to try out an LA-EA5 with your camera and lens?