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I just received my new Canon 100mm USM autofocus macro lens. I took a bunch of pictures outdoors, but I'm getting really crazy shallow depth of field with the pictures that's making it really hard to see the object in the picture. See samples below. Is this how all macro lenses are, and I just have to get better with it? Also, I'm finding that autofocus has its limitations, and I can zoom in more with manual focus. Is this also a limitation? Anyway to fix the DOF problem? I was on manual focus most of the time-could this just be a focus issue?

Also, I'm using a Canon Rebel T3 on mostly automatic everything mode. Can DOF be controlled?

https://i.stack.imgur.com/TZfKm.jpg

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Depth of field decreases rapidly as you focus closer, what you're experiencing is common to all macro lenses. It can only be remedied by stopping the aperture right down, or by using focus stacking.

Autofocus is also commonly unreliable with macro photography the best approach is often to set the lens to its minimum focus distance and then move the camera back and forth to achieve focus.

If you're attempting handheld macro shots in daylight (which is quite doable) I would set the lens to manual focus and the camera to aperture priority at f/11, and then set the ISO in order to get a reasonable shutter speed of at least 1/200s. Finally, don't give up - macro photography is hard and there are far too many people on the net making it look easy!

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The background and foreground focus is directly proportional to the focal plane distance. With macro lenses this is significantly closer and as such the angle that light can enter from areas in front of and behind the focal plane is greatly increased, as seen in this diagram.

Focal Plane

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The closer you are focused to a subject the smaller DOF will become, so macro lenses do in fact have really narrow DOF as a general case.

For something like the whole wasp to be sharp, you probably needed to select something more like f/9 or even f/10 in terms of aperture.

That is also why some people have taken to focus stacking, where you take a range of shots with slightly different focus and combine them using special software.

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    \$\begingroup\$ The reason why people focus stack versus stopping down is because of diffraction, which decreasing sharpness after a point, and sometimes due to the loss of exposure (e.g. must increase exposure time or ISO). \$\endgroup\$
    – eruditass
    Jul 14, 2011 at 0:11
  • \$\begingroup\$ Right, but even if diffraction were not an issue there's a hard limit a lot of lenses have - say f/22 - which you can go way beyond in terms of effective DOF with focus stacking. \$\endgroup\$
    – Kendall Helmstetter Gelner
    Jul 14, 2011 at 3:35
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All of the EXIF/IPTC data has been stripped from the wasp photo so I have no way of seeing what the aperture setting was, but increasing the aperture will increase the depth of field in your images. I would guess that the wasp photo was taken at about f/4 when f/11 may have given you a better result.

Here is a good explanation http://www.cambridgeincolour.com/tutorials/depth-of-field.htm

Here are some examples of different aperture settings in action http://www.digicamguides.com/learn/aperture-examples.html

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  • \$\begingroup\$ Set it to Av (Aperture priority) and step it down to f10 or higher. The but do read the explanation above. \$\endgroup\$
    – maxfridbe
    Jul 13, 2011 at 23:35
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You have two things that are decreasing your depth of field: First, you are using a mild telephoto lens. Second, and more importantly, your distance to the subject is far less than in a normal shooting situation. The result is that your depth of field can be as shallow as 1/4" with this lens. It's perfectly normal.

I have this lens and the L-Series 100mm macro and they are great lenses. They just take a bit of practice to use. Once you know to expect that beautiful shallow DOF, you'll be able to work with it. Nice images, BTW.

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Shallow DOF in macro is completely normal. At 1:1, you will find yourself needing to shoot at f/16 or even higher just to get your subject (i.e. a bug) in focus.

This is why a tripod is often necessary, as are additional sources of light (e.g. macro ring light) - to flood the scene with enough light so that you can shoot handheld.

Checking the DOF by stopping down the lens isn't helpful because at f/16 or higher the viewfinder image becomes so dark as to make it hard to discern.

AF in macro is very hard. With my 150/2.8 macro, I always focus by hand to get the focal plane just where I want it.

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