Macro extensions vs macro lens

[calamity]

Hi there! I'm looking to go into macro photography, but I want a lens that isn't so expensive just in case I don't like it. I was considering buying:

http://www.amazon.co.uk/MACRO-EXTENS..._bxgy_ce_img_b

But considering how cheap it is, I don't know if it would be reliable, so I'm considering a "Sigma 70-300mm f/4-5.6 DG Macro". It's a little bit more pricey but I think it would give me a good taste of getting into macro photography. I know it's not a true macro lens, but I'm just testing the waters here. What should I do in this situation? At the moment I am using a Canon 450D with a standard 18mm-55mm lens, so I really want to try something out with a better zoom. I used my dad's Minolta macro lens a couple of years ago, on his SLR, and I really enjoyed it so I'm hoping to get a lot better.

Are there any tips you guys can give me? I'm incredibly new to Digital photography and my understanding of SLRs is what I would deem just above average, but I'm not a professional by a long shot.

Thanks!

-Jane

[TCav]

Those are not very good extension tubes. Those aren't built very well, and sometims have light leaks and soem people have even had trouble connecting and disconnecting them. There are better extension tubes, like these: http://www.thkphoto.com/products/kenko/slrc-04.html

A macro lense is easier to use, since, while it will focus quite close, it will aoso focus at infinity. When using extension tubes, you can focus quite closely, but you also can't focus more than a few feet away. Also, extension tubes will magnify any flaws in the lens you use them with, so you should have a very good lens to use them with.

The Sigma 70-300 APO is a 1:2 macro lens and is quite good, as is the Tamron 70-300 Di LD.

[calamity]

Originally Posted by TCav

Those are not very good extension tubes. Those aren't built very well, and sometims have light leaks and soem people have even had trouble connecting and disconnecting them. There are better extension tubes, like these: http://www.thkphoto.com/products/kenko/slrc-04.html

A macro lense is easier to use, since, while it will focus quite close, it will aoso focus at infinity. When using extension tubes, you can focus quite closely, but you also can't focus more than a few feet away. Also, extension tubes will magnify any flaws in the lens you use them with, so you should have a very good lens to use them with.

The Sigma 70-300 APO is a 1:2 macro lens and is quite good, as is the Tamron 70-300 Di LD.

That's been very helpful, thank you! I was concerned about the extension tubes because they didn't seem to have a lot to offer and the description definitely felt like it was hiding issues I could have with it. But I'm glad to have had another opinion, as like I said I'm fairly new to this so any help is more than welcome! I think I'm going to go with the Sigma, especially as I have found one for a very, very good price! Thanks again.

[VTphotog]

I have an earlier version of the same Sigma lens (different lens coatings), and find it works very well at macro work. If you find you need more than the 1:2 ratio it gives, a teleconverter will increase the focal length and also the macro ratio ( a 2x teleconverter will get you to 1:1) without changing the camera to subject distance. Of course there are tradeoffs, such as losing 1 or 2 stops of light, and if the TC isn't of good quality, picture sharpness suffers.
On a further note, the Sigma lens tends to be a bit soft at its longest focal lengths in normal mode, so it isn't the greatest telephoto - not bad, just may need more sharpening in post-process.

brian

[TCav]

Plus, you can also use extension tubes with macro lenses. I used to use a 12mm extension tube with my Minolta 70-210/4.0 1:4 Macro 'Beercan' and got some excellent results. (The Beercan was pretty sharp at any focal length, which made it especially good with extension tubes.)