Hi, I'm another person who just got their Canon AE-1 out of a drawer (or from her mother's house after 7 years). At the time I bought a new Sigma macro lens, and I think it was around an 80mm-200mm. But I do not know how to read its size on the actual lens. Also I am interested in photography for slides of insects, plant ID (leaves to whole trees), and other outdoor nature photography. Along with the Sigma, I have a 52mm Canon macro and a regular 50mm. What other lenses for small detailed insect photos and for general 150 foot tall tree shots would I need?

-- Jean Gauthier (jeangaut@u.washington.edu), February 16, 2001

Answers

>How do you read the size of a Sigma lens?

It's written right on the front of the lens. There will be several sets of numbers. If this is a REAL Sigma macro lens, one will say either 50mm, 90mm, 105mm or 180mm. That's the focal length & the number that is most often quoted. Right after that there will be another set of numbers like 1:2.8 or 1:3.5. That's the maximum aperture expressed as a ratio (Think of it as a fraction of the length & the lower the number the better). There will probably be another number that starts with a zero with a slash through it. The two digit number that follows the zero is the filter ring size expressed in millimeters. it will probably be either a 52, 55, 58, 62, 67, 70, 77, or 82. If you have a filter mounted on it you will see that number on the side of the filter ring.

If, however, you don't have a real macro lens, but instead, have a Sigma zoom with a macro feature, the number will look a bit different. The first set of numbers will be something like 28-80mm and the set that follows will be like 1:3.5-4.5. It's still the focal length, but variable, followed by the maximum aperture, also variable.

At least that's how the newer Sigmas are designated. I have an older Sigma that reverses the order of the aperture and the focal length and introduces the focal length with a f=.

One thing's for sure. You don't have a Canon 52mm macro. They never made one. But they made plenty of lenses with a 52mm filter ring size. In fact the 50mm standard lens probably has a 52mm filter size. So, do you mean that you have a 52mm close-up filter for your Canon 50mm lens?

In order for anyone to recommend additional lenses for you we still need to know what lens you really have.

-- Jim Strutz (jimstrutz@juno.com), February 17, 2001.

Okay, here's what's going on. The Sigma macro has a 90mm focal length with a 1:2.8 maxium aperture, with a filter ring size of 52mm. It does say f=90mm.

The other Macro has a 28mm focal length with a 1:2.8 maxium aperture and a filter ring size of 52mm. I was reading off of the filter ring on it before. Actually I do not see the Canon logo on this lens at all- says "MC Auto CPC Phase 2 CCT" along with the other info on the front of the lens. What is the make of this one?

I also have a Canon 2x extender, the Canon 50mm lens (with a 1:1.8 maximum aperture) and a pile of filters. Let's see: a Sigma life-size attachment that has "use at f8-f22" on it, the filter ring presently on the macro lens says "CPC Phase 2 52mm skylight(1A) Japan", another filter ring just like it that says "UV-Haze" instead of "Skylight", another filter that says "Hoya 52mm UV(0) Japan",and a Canon polarizer.

Inventory complete- hope that helps.

-- Jean Gauthier (jeangaut@u.washington.edu), February 18, 2001.

hiya:

your 28mm lens is a CPC brand. this is a sort of 'store brand', fairly common; not bad quality but a lower priced wide angle. if it says 'macro' on it, it probably just means that it focuses closer than the usual 12 inches - i wouldn't use it for macro work.

the sigma sounds nice.

rick :)=

rick_oleson.tripod.com

-- rick oleson (rick_oleson@yahoo.com), February 19, 2001.

And the "MC" means it is multi-coated, or has the coating put on the glass in more than one layer.

-- Charles Spickard (cspick@home.com), December 13, 2001.