Macro Lens - Please Help!

[Blairfraser]

Hello there!

I need some help about a Macro lens.

I have a Canon 350D with a few lenses (some better that others!). I have an older Tamron 28-300mm 3.5-6.3. The thing that confuses me is that it says it is Macro. Although all the Macro lenses I have looked at are standard fixed lenses, including Canon and Tamron. I have tried to take close up pictures with my lens and they seem to work ok. I now have a few questions!

How good a Macro lens is my Tamron?
What would be the difference between my lens and say the Canon EF-S 60mm f/2.8 Macro USM lens or any other good Macro lens?
Does it just say Macro on my lens to fool me???? :-)

Any answers you have would be great!

Thanks for looking.

Blair

[AdrianW]

To be honest I think labelling the 28-300 a macro lens is a little misleading, on a 35mm camera it's capable of a reproduction ratio of 1:2.9. Due to the crop factor of the 350D it becomes an effective 1:1.81, which is better, but still not life-size.

What I consider to be the true macro lenses have a reproduction ratio of at least 1:1, often called life-size. That means that at maximum magnification the size of the object in front of the camera is the same as the size it appears on the film.

In reality as you're using an APS-C sized sensor most macro lenses will be 1.6:1 i.e. the size of the image on the sensor will be 1.6x larger than the size of the object in real life.

The 60mm has a reproduction ratio of 1:1 on an APS-C body, which means it's slightly less macro than the 100mm EF Macro, or the Tamron 90mm which are both 1:1 on a full-frame or 1.6:1 on APS-C.

Hope I haven't confused you too much!

[Floydian]

Blair,

A real macro lens shoots 1:1 images.
Your Tamron is not a real macro lens. Also on my lenses they put the word macro, a big laugh because it comes not further than 1:4.

The 60m/m is a real macro lens and if that is what you want it's good choice...
See here for a more detailed description.
For something special they also have a 65m/m extreme macro, see here the details.

Good luck,

Henk

[mossphoto]

Blair-

Also, most macro lens have a flat focus plane, as opposed to a curved one for normal lenses. This is one of the differences in a true Macro lens. I'm a Nikon snob, so I'm not familiar with Canon's macros, but I'm assuming its the same.

~V~

[AdrianW]

Note: Although the MP-E 65mm offers amazing close up potential, it's hard to use compared to a normal true macro lens. On the MP-E 65 the focussing ring doesn't quite change the focus, effectively it adjusts the extension of the lens, rather like using bellows. In other words, the focussing ring adjusts the magnification, not the distance the lens is focussed at.

At 5:1 it's also very very difficult to use handheld. It's a fascinating lens, but it's a major challenge to use it well; at least compared to the standard true macro lenses.

An interesting article on LL here