Kx and Tamron SP 70-210 compatibility

I have an old Tamron SP 70-210 adaptall lens with a KA adaptor which I can fit onto my Kx.
I have permitted the camera to accept it but focussing is very hit and miss (I realise this could simply be operator error). I have no problem with doing everything manually.
When I switch on the camera, it asks me to put in the focal length : does this mean I need to adjust this every time I take a photo using a different length of zoom ?

The other big question is that I cannot work out how to adjust the f-stop and I've noticed on the Exif data that it comes up as f-0.

I'm very much a beginner so I'm rather hoping that I am missing something simple ...... and would greatly appreciate some help!

Thanks in advance.

Because there is no electronic contact between camera and lens, you need to input the focal length so that the SR system will work optimally. In theory, you would input this for any focal length selected, in practice you might get away with putting in the mid point of the range.

As regards the aperture, you need to select the "Use of aperture ring" in the custom menu and set it to "permitted" - you will then be able to meter manually in stop down mode. There is no need to reset this function when returning to more modern lenses, it will be fine.

It looks like your ka adapter isn't quite working. You should have the aperture appearing in the viewfinder. (Presuming the lens is set to the A setting or whatever the equivalent is!) Try cleaning the contacts, if that doesn't help, disengage the lens in the mount, and then very slowly turn it back into place. It may start working just before the lens clicks into place.

You may want to try manual mode with the green button metering instead.

Re focal length, input the one you'll be using, or if you plan to use lots of different focal lengths, input the smallest one. Better the shake reduction is less efficient than over compensates.

There's a very good chance it could be this.

Many thanks for the help - I had already set the use of aperture ring to "permitted" so I knew it wasn't that.

However, it looks as if my error was not setting the lens to the A setting. I've now done that and when switching on, I can now adjust the aperture which is great.
With any luck I will now be able to use it in the same way as I do the 18-55 lens, though of course there will be no automatic focus.
I'll play around with the focal length input until I see how it works best.

Thats good news, Blaze.

You are real stars!
Setting the lens to A was definitely the answer.
I'm still a little rough on the focal length, but that will come with practice.
But .... the good news is that I can use the lens with the Kx!