How is a macro lens differ from a regular lens?

[markubig]

I was going to ask what the difference was between the EF 50/1.8 and the EF 50/2.5 macro, but then i figured the difference in price was an answer and probably directly related to the build-quality.

How about if I ask what the difference is between the EF 50/1.4 and the EF 50.2.5 macro? They are somewhat similarly priced, but what makes the 2.5 a macro and the 1.4 not?

just curious . . .

[tim]

To me, a macro lens is one that can do 1:1 at it's minimum focusing distance. Most 100mm macros do this, the 50mm ones not so much, and the 180mm macros are even better - 2:1, so longs are larger than life size on the sensor.

[markubig]

My understanding is 1:1 means that the size of your subject in the photo is the actual size of the subject. And 1:2 means that the size of the subject in the photo is 1/2 the actual size of the subject. The 50/2.5 is 1:2. Is the 50/1.4 also 1:2 since they are the same focal length? or is there a difference in the design of the lens?

[TammieO]

Canon's 50mm macro is half life size. The macro lenses will allow you to get closer to the subject and still focus.

[CyberDyneSystems]

It lets you focus close enough to give 1:1 images..

[PJ Saine]

How about if I ask what the difference is between the EF 50/1.4 and the EF 50.2.5 macro? They are somewhat similarly priced, but what makes the 2.5 a macro and the 1.4 not?

just curious . . .

Just like apertures, there is one single focus setting that produces the single sharpest image. Most photographic lenses are designed so that this is the infinity setting (the most commonly used setting).

Macro lenses are optimized for a closer focus: often a 1:10 reproduction ratio on a macro lens that focuses to infinity. Macro lenses are also more often a symmetrical lens design.

The sharpest macro lenses are those small, short focal length lenses that fit on bellows. General use macro lenses (like the 50mm macro) are quite good. A zoom lens with a macro setting won't cut the mustard if you are a very critical shooter.

PJ
www.pjsaine.com

[markubig]

Thanks for your replies, all.

It just came to mind because I had read an earlier post on macro lenses, and then I thought to myself, "My Tamron 28-75 says '1:2.8 Macro' on it . . . does that make it a maro lens?"

So if I use my 50/1.8 to take a picture of a bee on a flower, is that not a true macro photo?

[CyberDyneSystems]

Lots of lenses in the consumer price range stamp the word "macro" on them.. no one really knows why por what criteria they use to make this unfounded claim.