Beginners questions ~ Extension tubes.

[iant]

As my new found interest in photography develops, Im looking more and more at macro and indeed bought the Sigma 105mm Macro.

Looking at many of the excellent shots in the macro section, many others have this lens but are taking far more detailed shots than my meagre experience allows, and often I see that an extension tube or ring has been used.

1) What exactly are these things and what do they do?

2) Can you recommend one in particular for this lens?

3) I see Jessops sell Canon ones at up to £200 but there are some incredibly cheap ones on Ebay, will they do the job?

Thanks

 

[Dogfish_magnet]

Personally i use the Kenko tubes as they retain the electrical contact between the lens and the camera allowing full control over aperture unlike the cheap ebay ones, and dont forget to get maximum magnification you will need to use manual focusing ,and wind the lens all the way out until you see 1:1 on the barrel the focus by moving the camera.

 

[iant]

Personally i use the Kenko tubes as they retain the electrical contact between the lens and the camera allowing full control over aperture unlike the cheap ebay ones.

Hence why they are so cheap then. This is what I love about this place, you learn something every day.

 

[RobertP]

Hold the lens in front of the camera body say about an inch away from the normal fitted position then look through the viewfinder on the camera. that will give you a rough and clumsy idea of what tubes will do