Canon EF 100 f/2.8L IS Macro autofocus?

Aug 10, 2012
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Good Afternoon,

Santa gave me the Canon EF 100 f/2.8L IS Macro for Christmas, and this is my first experience with a macro lens. I took about 100 photos indoors yesterday, and about every 10th photo the autofocus hunts for 5-10 seconds before it acquires focus. The indoor lighting is adequate, but I would not say the lighting is bright. I've been taking a mixture of portrait and macro type photos.

Most of the photos I've taken appear to be in focus, but I'm still learning the lens. Is it normal for this lens to hunt at times to lock focus, or do I potentially have a bad copy?

Here are my settings with my 5D MKIII

* lens is on FULL mode
* camera is set to Case 1 with AI SERVO
* selectable AF point is 61 points
* manual select: spot AF
* The camera is on manual mode with auto ISO, and I've been taking photos with apertures between f/2.8 and f/8 with shutter speeds between 1/60 - 1/200.

Also, I'd appreciate any advice on recommended aperture and shutter speed settings with this lens for both portrait and marco photos.

Thanks!
 
When you shoot macro you should limit the focus area. If it starts hunting, it has a long way to go and that takes time. IS becomes a bit less effective when you get really close, so you should use a slightly faster shutter speed than you would normally use. Personally I prefer to shoot MF for macro. I also use live view quite a bit.

As a portrait lens you can use it like any other lens. But it might be that you prefer to use the other focus limitation alternative, also to avoid hunting.
 
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When shooting macro, did you have IS turned on or off?

Had similar issue with this lens mounted on 5D MKII, camera/lens on a tripod with the IS engaged but not in AI SERVO. The auto focus would hunt. As a result, I had a lot of fuzzy images of completely still subjects.

Someone here suggested that I should have disengaged IS.

Isn't Case I a default tracking mode? I realize that there are many who use AI Servo all the time, even for still subjects.

But AI SERVO mode is in essence anticipating that the subject could move. Wouldn't this setting pick up vibrations that could be interpreted as movement?

Don't quite understand the rationale for shooting still subjects in AI SERVO mode. :o
 
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One Shot AF should be used for most applications. The lenses focuses to 1:1 at the MFD, but if you're closer than the MFD, the lens cannot focus. It will take a while for it to give up though. To test this, step back a foot and try again. If it locks, get closer and try again. At some point, you'll be closer than the MFD and it won't be able to lock.

For macro subjects, use the aperture to control the DOF. If it shutter speed drops too much, then adding light (i.e. flash) would be the way to go.
 
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slclick said:
I'm curious to know just how much Macro folks that are recommending using AF are doing? It's a sizable part of my portfolio and AF isn't ever part of the equation.

I use AF for handheld stuff and with lower magnifications. For higher magnifications and for greater DOF, the tripod, rails and flashes come out and AF stays off.
 
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It depends on your shooting style and subjects. With a tripod and stationary subjects, live view with 5x or 10x magnification and manual focus gets me the best results.
When shooting stationary subjects handheld at macro distances I usually focus manually by moving the camera forwards or backwards.
When shooting moving subjects like flying insects at macro distances autofocus will give me the best results because AF can focus and keep focus (AI servo) a lot faster than I can do manually.

To get enough DOF at macro distances for a single shot I use apertures between f/8 and f/16 (depending on available light and the shutter speed I need) or focus stack with a macro rail (your subject needs to be stationary for a long time) and use values between f/5.6 and f/8 (the sweet spot for resolution and sharpness) for the individual shots.

The hybrid IS on the EF 100 f/2.8L will “only” get you something between 1 and 1.5 stops stabilization at macro distances, so if you shoot handheld the lowest you can go is about 1/30 sec (if your subject doesn’t move that is). At normal distances the IS will give you 3 to 4 stops.
 
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slclick said:
I'm curious to know just how much Macro folks that are recommending using AF are doing? It's a sizable part of my portfolio and AF isn't ever part of the equation.

Um, can't the lens be used in many different modes for many different things? If I'm shooting at macro distances or products, I'm on a tripod and manual. If I'm using the lens for other things, I may use that handy modern AF feature that's included for free in my lens. Not sure why you are trying to call people out because they may use their tools differently than you.
 
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When you say it hunts for several seconds every tenth shot or so, has anything changed between shot #9 and shot #10? Does this happen more when you're putting it to macro or non-macro use? I've never used a macro lens for non-macro work which didn't hunt when switching between subjects at significantly different distances from the camera, and this gets worse as the light gets lower (that doesn't stop me from using my 100L that way, though, because it's a fantastic lens in every other way; using the focus limiter and grabbing the focus ring largely solves the problem). I would also note, as others have, that manual focusing tends to work better for macro work. Wonderful though good AF is, and I don't think any dslr systems can beat Canon in this area, it's probably overrated and has its limits; and one such is when you need to make fine, precise focusing choices such as are typically involved in macro work (too bad dslrs are lousy tools for manual focusing unless you use live view).

Remember also that if you're using the lens wide open, when you get really close, as the lens lets you do for macro work, depth of focus is exceptionally thin and the slightest imprecision in focusing, including the slightest movement of the camera, will result in an image in which either the wrong thing or, more likely, nothing at all is in focus. What aperture were you using for your macro shots? (This may not have much to do with the hunting, if any, you experienced doing macro shots.)
 
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Gino said:
Good Afternoon,

Santa gave me the Canon EF 100 f/2.8L IS Macro for Christmas, and this is my first experience with a macro lens. I took about 100 photos indoors yesterday, and about every 10th photo the autofocus hunts for 5-10 seconds before it acquires focus. The indoor lighting is adequate, but I would not say the lighting is bright. I've been taking a mixture of portrait and macro type photos.

Most of the photos I've taken appear to be in focus, but I'm still learning the lens. Is it normal for this lens to hunt at times to lock focus, or do I potentially have a bad copy?

Here are my settings with my 5D MKIII

* lens is on FULL mode
* camera is set to Case 1 with AI SERVO
* selectable AF point is 61 points
* manual select: spot AF
* The camera is on manual mode with auto ISO, and I've been taking photos with apertures between f/2.8 and f/8 with shutter speeds between 1/60 - 1/200.

Also, I'd appreciate any advice on recommended aperture and shutter speed settings with this lens for both portrait and marco photos.

Thanks!

macro shooting does reduce the light the AF sensor gets
changing the AF limiter can help it from getting lost in a zone far away from what is needed
 
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slclick said:
I'm curious to know just how much Macro folks that are recommending using AF are doing? It's a sizable part of my portfolio and AF isn't ever part of the equation.

With the USM macro lenses from Canon macro AF works quite well, especially on 5D3/1DX or 7D (the latter goes in a specific ultra-speed macro AF mode automatically). I know the old macro crowd treats AF like the plague, but honestly, there are times that it simply works better than trying manual and other times where it works equally as well and is more convenient. Of course in some scenarios manual will be better. But don't just toss out AF+macro.
I even successfully use it (AF) on a regular basis even with a full set of extension tubes on, you often nail it even right on a bug's eye.

As for IS, it can nab you some shots you'd have needed flash for otherwise (although it is best done with high speed continuous shooting and then you might get 1 out of 5 utterly crisp; without IS maybe you get 1 out of 200 which is not so good). And for more backed out pseudo macro shooting the IS really helps. And even when using flash it helps since it helps you center a stabilized frame on the subject as desired.
 
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Lots of good advice already. The 100L isn't the fastest focusing lens out there, using the focus limiter really helps. It does hunt sometimes. Here's a comment I made 2.5 years ago:

neuroanatomist said:
Also, I've found that my 100mm f/2.8L Macro IS seems to hunt for focus a bit more in low light than other f/2.8 lenses.

Also worth noting is that while it's an f/2.8 lens, it's actually in AF Group C, which is typical f/4 lenses and f/2.8 + 1.4x TC lenses. You get 41 cross type points, but none of the high-precision f/2.8 crosses.

Spot AF does restrict the area used for AF, so make sure there's a contrasty feature in the box.

Servo AF is fine - I haven't seen it mentioned in 5DIII/1D X technical documents, but the 7D (and 1DIV?) had a dedicated macro mode in Servo that compensated for the drift back and forth of the photographer, and I suspect the new bodies have it, too. It's activated automatically if you're using a Canon macro lens with a close subject in servo mode (there is no indicator that it's active, though).

As for recommended aperture/shutter speed for portraits/macro - macro needs as narrow an aperture as you can get for more DoF. Light becomes limiting fast, and the IS benefit is reduced to at best 2 stops at 1:1. For portraits, that's preference and depends on subject distance. I'd use f/2.8-4 usually, but for something like a headshot, you'd need f/8-11 to get the ears/hair in focus along with the eyes.
 
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neuroanatomist said:
Lots of good advice already. The 100L isn't the fastest focusing lens out there, using the focus limiter really helps. It does hunt sometimes. Here's a comment I made 2.5 years ago:
neuroanatomist said:
Also, I've found that my 100mm f/2.8L Macro IS seems to hunt for focus a bit more in low light than other f/2.8 lenses.

neuroanatomist is probably one of the few members being able to quote himself :-> ...

... but what he wrote is also my experience, the hunting seems a bit worse on my 6d vs. my 60d, but it's there on both. The best advice is to focus on some contrast part, that helps the af to lock on ... and if shooting tripod live view with Magic Lantern (focus peaking (and stacking)) is the best option anyway.

100 said:
The hybrid IS on the EF 100 f/2.8L will “only” get you something between 1 and 1.5 stops stabilization at macro distances, so if you shoot handheld the lowest you can go is about 1/30 sec (if your subject doesn’t move that is). At normal distances the IS will give you 3 to 4 stops.

This has been discussed a lot, and my experience is that at 1:1 macro the effect of IS is about ... zero. It gets better the more you distance the camera from the subject, but the IS is really best starting with your typical "full flower" shot type.
 
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