Hi, I just purchased a set of macro extension tubes for an assignment I have for uni, I have never used these before and I am sure they work fine but perhaps it is me with the problem.

So I have attached the tube, first all of them, now just one and both times I have just blur through my lens, I understand you have to focus manually but should I at least be seeing part of the object I am photographing?

What am I doing wrong?

Can someone please help?

Kat