Hi all,
I am going on a trip to Costa Rica this November and am trying to get myself as ready as possible. I am sure there will be many butterflies and other insects along with flowers to photograph. I am trying to decide if I should bite the bullet and get a dedicated macro lens or if a quality tube kit would suffice. I am an amateur so will not be doing a ton of macro photography but I don't want to miss shots I may never see again.
Thanks
One difference is that extension tubes changes the way the lens focuses. In fact, near 1:1, the lens really does not focus anymore, its focus ring has such little range and effect we'd say it no longer focuses (focus is no longer useful). Instead, we move the camera back and forth hunting for the one distance where it will focus. Which is difficult on a tripod, and is the reason that geared focusing racks are used (to move the camera back and forth). If you want it to focus at a different distance, you change the tubes appropriately. Which is Not handy.
Whereas the macro lens will simply focus at any distance, like any lens does, but of course very much closer too. Easy as pie.
We only move the camera to change the magnification of the view we see. We get used to this great convenience.
Plus the macro lens is optically corrected for the closer distance, where a regular lens is not.
You would want a pretty short extension tube for butterflies and flowers.
Butterflies and flowers may not need either one. Insects might, but we typically don't do 1:1 macro blowups, but instead are standing back a few feet. A "closeup filter" is handy for that. Basically just a magnifying glass screwed on to the front of the lens. Can be used on a zoom lens to give more telephoto versatility. It does prevent focusing at infinity then, but it will focus close. Not nearly 1:1, but at a couple of feet, just about right for flowers and butterflies.
These "closeup filters" are marked with "diopter" strength, and the meaning is 1/diopter is the maximum distance they can be used. For example, 2 diopter works at up to 1/2 meter (lens focused at infinity then, and can focus closer).
There are good ones (double elements of glass, the Canon 500D is one of the good ones, the 500 means it is 2 diopters, or 1/2 meter). And there are cheapies, not as good. These are just screwon "filters", works on any camera with a matching filter thread size.
Extension tubes and macro lenses both reduce the light at high magnification, and require longer exposure. The closeup filters do not, but they are sharper when stopped well down, like say f/11 or so.
I think most of us quickly find the macro lens to become our favorite lens. Very versatile and handy, we don't have to keep changing tubes or filters.