Macro lens vs regular lens

I see people shooting portrait type pics with their 100L macros.....they love the sharpness, etc, etc..... Why buy a 135 or 85, etc when you can use the 100 and also use it for macro work? What exactly makes a lens macro (magnification difference?) and why can you use a macro lens as a regular lens also? Why not just make all lenses macro lenses then?

A true macro can focus close enough to get at least 1:1 image magnification on the sensor - so your 50 macro, EFs 60, the various 100mm macros and the 180 can all do that. You are certainly able to use those lenses for regular use but in my experience they aren't particularly fast focusing. I chased my dog all over the yard with my 70-200 f2.8 L and she kept coming too close, so I had a ton of blurry pics (inside MFD). So I thought, AHA! I put my 100mm macro on the front, chased her all over and now I have tons of blurry pics because the AF can't keep up. Horses for courses, I guess.

The 85 and 135 lenses are particularly fast focusing lenses, which makes them outstanding for indoor sports work and that sort of thing when minimum focus distance doesn't matter.

Then you have sort of hybrid lenses, like the 24-70L that has a fairly close MFD, so they paint a macro sticker on the side. It's not a 1:1 macro lens but it is very useful to have a close MFD on a lens like that.

Higgs Boson wrote in post #13554164
I see people shooting portrait type pics with their 100L macros.....they love the sharpness, etc, etc..... Why buy a 135 or 85, etc when you can use the 100 and also use it for macro work?

One reason why I own the 100L and not those other lenses If I was doing a ton of portrait work, that'd be a diff story.

Higgs Boson wrote in post #13554164
I see people shooting portrait type pics with their 100L macros.....they love the sharpness, etc, etc..... Why buy a 135 or 85, etc when you can use the 100 and also use it for macro work? What exactly makes a lens macro (magnification difference?) and why can you use a macro lens as a regular lens also? Why not just make all lenses macro lenses then?

Macro lenses aren't usually as fast focusing, and don't usually open as wide - my 60mm macro is f2.8 as opposed to a standard prime more down to 1.8. But I'll take that for the option of getting really close. For me the 60mm also fills a focal length gap between 55mm and 70mm.

I don't do a lot of portraits but if I can use my 100 L macro I will. I have got a 50 f1.8 but I prefer the IQ of the 100. I've recently got a 5DMkII which came with a 24-105 f4 L and I'm starting to use that for some portraits too purely for the IQ. It all depends on what I'm shooting and how it's set up.

Higgs Boson wrote in post #13554164
I see people shooting portrait type pics with their 100L macros.....they love the sharpness, etc, etc..... Why buy a 135 or 85, etc when you can use the 100 and also use it for macro work?

Why buy a 100 macro when you can use the 135L and 50L for macro work with a few extension tubes?

100 mm is a great FL for portraits, as the AoV on FF is approximately the same AoV as that of the human eye when looking somebody in the face.

There is that, plus as optimal a correction as possible for field curvature, and close distance focusing, where you get much larger refraction and hence enlargement of any optical faults/optical aberrations.

Because they will generally work at longer distances quite well too, unless they get very specialized.

Ah, here is a catch: maximum aperture.

An F/1.4 macro lens would become probably 4X or more as expensive as a F/2.8 macro lens, because of the complex aberration corrections required to function as well in close focus modes. There is a reason why F/2 macro lenses tend to go to 1:2 only. Even the 50 F/2.5 Compact Macro becomes a 70 mm F/3.5 when using the macro converter to go to 1:1.

This doesn't stop me from using my 135L and 50L from using them for macro, BTW. In fact, I found the bokeh of these lenses and the rendering in general of this pair in macro mode (with tubes) to be better than both 100 Macro and 100L Macro, but that is my personal preference. YMMV.

Now, if Canon would make a 105 F/1.4L, which would just be possible with a 77 mm filter thread, I would likely jump on it .

Kind regards, Wim

Thanks for all the replies.... What is the magnification ratio of a non macro lens?

Higgs Boson wrote in post #13555208
Thanks for all the replies.... What is the magnification ratio of a non macro lens?

That varies a lot, from lens to lens. Essentially it depends on FL and MFD. If magnification isn't given, it can be calculated with the aid of some algebra and the lens formulas.

However, Canon provides (rounded) magnification factors in their lens tables. All non-macro 50 mm in the Canon stable focus to 0.45 m (1 1/2 ft), and their magnfication is approximately 0.15x at MFD (0.146 X if you calculate this yourself).

A few more examples:
85L & 85L II 0.11 X
85 F/1.8 0.13 X
100 F/2 0.14 X
135L 0.19 X
135 F/2.8 0.12 X
200 F/2.8 0.16 X
etc.

Kind regards, Wim

Another point to consider is that macro lenses have a more crude control over their focusing at longer distances than regular lenses. A macro lens has very fine control over the focus up to around the 1:2 magnification point; however as you start to focus further away to your half a meter, 1m, 5m etc.. the amount of turn on the focusing wheel needed to shift the focus decreases a lot.

The result is that manual focusing with a macro lens at longer distances can be much more tricky because small changes in the focusing wheel will shift the plane of focus further than if it were a regular lens.


In addition you've also the point raised about autofocusing speeds with macro lenses typically having a slower focusing speed than regular lenses; even though most do have limiter switches this speed can still be less than for a dedicated regular lens. Best AF speeds tend to be on the canon ownbrand lenses - 100mmL is about the fastest you'll get.

svarley wrote in post #13554578
A true macro can focus close enough to get at least 1:1 image magnification on the sensor - so your 50 macro, EFs 60, the various 100mm macros and the 180 can all do that. You are certainly able to use those lenses for regular use but in my experience they aren't particularly fast focusing. I chased my dog all over the yard with my 70-200 f2.8 L and she kept coming too close, so I had a ton of blurry pics (inside MFD). So I thought, AHA! I put my 100mm macro on the front, chased her all over and now I have tons of blurry pics because the AF can't keep up. Horses for courses, I guess.

The 85 and 135 lenses are particularly fast focusing lenses, which makes them outstanding for indoor sports work and that sort of thing when minimum focus distance doesn't matter.

Then you have sort of hybrid lenses, like the 24-70L that has a fairly close MFD, so they paint a macro sticker on the side. It's not a 1:1 macro lens but it is very useful to have a close MFD on a lens like that.

I always like it when the first response nails it. Should have been a two post thread (not that everyone else's input isn't valid, this just sums it up perfectly)

wimg wrote in post #13555094
...if Canon would make a 105 F/1.4L, which would just be possible with a 77 mm filter thread, I would likely jump on it .

Kind regards, Wim

Be still my heart! (LOL)

Dave