Save yourself the stress Peter, it's not as though you've blown a fortune on these things.
It will still be usable, but you'll always be at the same aperture, either wide open or fully stopped down, I don't know enough about the Nikon system to be able to say which.

Thanks fellas - I like your images Lee. This is entirely my fault but, as you say Duncan, I've not lost a fortune. I'm going to wait for them to turn up now and have a play. I'm sure I'll get something out of them. If not I won't lose too much sleep. It's good tho' to share the experience, one of the great benefits of this forum.

im pretty sure the aperture is fully stopped down, because the view finder is really dark, you would just have to make sure you have plenty of light.

I agree Lee if I take it off the camera I can see it's stopped down, the motor opens it up, you can watch it through the lens in good light. So yeah I'm thinking maybe flash will help - scare the bees tho':) Whatever it'll be something to play with.

you could shoot with sunlight and us a reflector too.

Yes I was thinking of that too, thanks Lee. The good news is I came across a 50mm f1.8 AI-S lens from a local lad at £50:) so along with the tubes I'm now waiting for that. I know the lens sounds almost too cheap to be true but I'll write more when I've tried it.

sounds like it could be idea..... my 50mm AFD was only £100 new so it might be ideal....fingers crossed huh...;)