quick question on 100mm macro

[Sfordphoto]

I noticed that the 100mm macro has a focus distance limiter. Is this helpful with the focusing speed of a macro lens? As in will it decrease focusing time?

My understanding is that macro lenses are usually slow focusing, because they can focus really close and thus must check a larger distance for the subject. By limiting the range, can one achieve focus faster such that it will be just as fast as, say the 100 f/2?

Curious because I would love to get a macro lens that would double up well as a portrait lens.

Thanks in advance

[Jaetie]

Is this helpful with the focusing speed of a macro lens? As in will it decrease focusing time?

yes.

By limiting the range, can one achieve focus faster such that it will be just as fast as, say the 100 f/2?

no.

[Red Dot]

the focus is the same speed no matter,
when in low light, the focus will go from infinity to MFD until it locks. the , limiting switch does not make this faster, it simply makes MFD longer, and thus the whole range is decreased. (which makes it appear quicker)

[Sfordphoto]

hmm ok
but in normal use is the 100mm macro that limiting in terms of AF speed?

[philthejuggler]

hmm ok
but in normal use is the 100mm macro that limiting in terms of AF speed?

Not in my opinion - it focusses reasonably quickly in decent light - I wouldn't use it to track a moving subject in low light though!

Phil

[Karlos]

I always use manual focus with the 100mm when shooting macro.

The AF is ok for things like portrait work, but as Phil says, it doesn't really shine in low light conditions.

[Red Dot]

mines fine focusing, its great, what more could you want. you could just get away with sports but if used as a portait lens it couldn't be better. macro should be done manual anyway.

[Lester Wareham]

I noticed that the 100mm macro has a focus distance limiter. Is this helpful with the focusing speed of a macro lens? As in will it decrease focusing time?

My understanding is that macro lenses are usually slow focusing, because they can focus really close and thus must check a larger distance for the subject. By limiting the range, can one achieve focus faster such that it will be just as fast as, say the 100 f/2?

Curious because I would love to get a macro lens that would double up well as a portrait lens.

Thanks in advance

In fact the 100mm macro has a very acceptable focus speed, genrally I don't notice a difference between it and any other lens.

Some people think it is slow because if you let it hunt with a low contrast subject it has an huge focus range to hunt over, so this takes time. The focus limiter switch reduces the focus range to something like that of non-macro lens and so reduces the hunt time for low contrast subjects.

It is useful to have but I almost never use it. The only time it has been necessary was with a low contrast subject in dim domestic lighting, almost any lens will have trouble in those conditions.

[John_B]

Sfordphoto,
Yes the limit switch does help speed up focus for subjects like portraits.

Yes the Canon 100mm f/2.8 is an excellent portrait lens and also an excellent macro lens. :)

[Sfordphoto]

Thanks for the info :)

[Sfordphoto]

mines fine focusing, its great, what more could you want.

haha, just asking a question