Sigma 105 macro (ex tubes?)

[addicknchips]

I’m interested in starting to do some macro photography. By all accounts the Sigma 105 is as good, if not better than the Nikon 105 vr. I’ve seen this lens for around £370, which seems reasonable.
What are peoples experiences of using this lens?. A lot of the images I’ve seen from this lens arn’t the extreme close ups I’m hoping to achieve. I.E close enough the see the eyes of an insect. Would I need to also invest in extension tubes? What are the drawbacks of using these? I have a Nikon d610 along with the tamron 24-70 and sigma 70-200. Would extension tubes act as a macro conversion on the sigma? Excuse my ignorance, but have not researched extension tubes until now.
Thanks in advance.

 

[odd jim]

Have a look at some of my threads in the Macro section, most of the new ones were taken with the Sigma 105 Macro (the new OS version).

Its an awesome lens, easily the sharpest of my 10 plus lenses!

 

[rob-nikon]

I've recently re-bought the sigma 105 os. It's a nice lens and reported to be as good as the Nikon. I only sold it through lack of use but I've decided I need to do macro to add some different images to my portfolio I decided to buy a new one. I've also bought some extension tubes so can't wait to try both together. At its current price new it's a bargain, I bought my first one second hand for more. I'm looking forward to summer again.

 

[Cap'n Bill]

I'm using it on a Sony. Very sharp, quite quick autofocusing and handles well on manual focus. Quite a chunky lump though.