Very dumb macro question

[Ja Di ksw]

So, I'm not really sure exactly what macro gives you. I know you can be closer to the subject, and that it magnifies it bigger, etc. I guess it boils down to this:

Lets say I have 3 lenses and I shoot the same subject from the same distance. A 135mm, a 135mm macro, and a 200mm (or something similar).

I'm assuming the subject would be "bigger" in the macro and 200mm (or 300mm, or whatever example you want), but would anything else be different? Could a 200mm (300mm, whatever), be used in place of the macro and get the same results with some cropping? Assuming I didn't need to be 10 cm away from the subject or something.

Thanks.

 

[iBookG4user]

A macro shot is where the subject is the same size as real life on a 24x36mm recording plane (whether it be film or digital). Macro lenses are specifically designed to focus close enough to allow you to get a 1:1 ratio where the subject is real life size. Normal lenses cannot focus close enough to allow you to get a real macro shot, the focal length of the lens has very little to do with macro shots. Longer macro lenses are made so you can be further away while retaining the 1:1 ratio for life size shots.

 

[greg555]

A macro shot is where the subject is the same size as real life on a 24x36mm recording plane (whether it be film or digital). Macro lenses are specifically designed to focus close enough to allow you to get a 1:1 ratio where the subject is real life size. Normal lenses cannot focus close enough to allow you to get a real macro shot, the focal length of the lens has very little to do with macro shots. Longer macro lenses are made so you can be further away while retaining the 1:1 ratio for life size shots.

Close. Life size means the image on the film/sensor is the same as the object. So a frame filling head shot on an 8x10" large format camera is life size.

Greg

 

[disdat]

I can give you a real life example. I have both a 300mm f/4 IS lens and a 100mm f/2.8 macro lens.

With the 300mm, I have to stand at least 5 feet away from my subject in order to focus.

With my macro lens (even though it is shorter focally) I can get inches away, thus making those shots "larger" or more macro than my 300.

I have found I cannot really get the same quality snap w/ the 300 that I can w/ my macro, although I do enjoy the 300 for some close up shots.

I have sets for both lenses on my flickr stream
100 macro
http://www.flickr.com/photos/disdatmac/sets/72157604362182265/

and 300
http://www.flickr.com/photos/disdatmac/sets/72157604589273159/

 

[Ja Di ksw]

Thank you all, that was helpful - especially the example photos. You have some really nice shots in there, disdat!

Edit: One more quick question, sorry. So if I'm not focusing close at all (subject is 10 feet away or something), will there be any difference between two lenses where everything (shutter speed, aperture, focal length, etc) is the same, but one is macro and one is not?

 

[disdat]

If you have two 100mm lenses, and you are standing 10 feet away w/ everything the same, then no, there shouldn't be any difference between a macro and a non-macro.

The bonus of a macro is it can usually be a nice portrait lens too!