I have a 50mm 1.8 IImacro and went to a workshop with a dude who specialises in macro and he tells me not to buy teleconverters or magnifying filters but extension tubes as a cheap, easy no frills option for beginners macro work.
So I go on Ebay and find these and bid for them and won them for 99c plus 15.00 postage: didnt expect to win them then when I did I got the same feeling you get when only 5 other people are in your cinema waiting for the beginning of the movie your girlfreind selected (Godzilla) ..
A. Am I mug for paying so much postage on them (well yeah) but
B. Will they do the job of physically shifting the further away from the sensor of the camera and will give me the same results as say a 25mm brand name extension tube without forking out over a hundred bucks for the pleasure of having written on a peice of plastic . Im told these tubes all do the same thing at the same size - maybe these ones will not allow autofocus and thats the rub ?