Canon5D MK III,Canon 6D,Canon 17-40 L ,Canon 24-70 MKIIL , [/COLOR],Canon 70-200MkII L ,Sigma Fisheye 15mm 2.8 ,Canon 2xMk3 Extender, 430EX11 Flash , Lee Big Stopper & Other Lee Filters.
Manfrotto 055XPROB + 322RC2 + MBAG80P.
Critique is allways welcome, Any help and advise will allways be appreciated.
davidwalkerphotography.net
You could use them. They will give you greater magnification, however keep in mind that they will also reduce you MWD.
I found that I wasn't that into macro when I had mine as well as my macro lens so sold mine.
Yes, you can use the Kenko tubes on your 100mm macro lens. Using all the tubes together will give you approx 1.8x magnification, rather than the 1x maximum magnification that you currently have at the minimum focus distance.
Bear in mind that autofocus won't work too well (if at all) at 1.8x, largely due to the loss of light (I suspect you'll lose ~ 2 stops of light?). You minimum working distance to your subject will decrease from 15cm to approx 11cm. Given the loss of light, you really need some form of flash to supplement natural light when you've got all the tubes on.
Overall, I'd recommend getting the tubes - they're an inexpensive way to broaden your macro lens' capabilities.
Linked here is an excellent technical site covering popular macro lenses and the impact of tubes etc.
Thanks for your advise i think i will get them.