Macro Lens - What separates them from others?

[Bombsight]

Been looking at the Canon EF 100mm f/2.8 L IS USM Macro Lens ...... http://www.bhphotovideo.com/bnh/controller/home?O=&A=RetrieveSku&IC=CA10028LMIS&Q=


I've seen some awesome close-up shots of insects and other things done with "extension tubes". I've got to experiment with that kind of photography![:O]


Could I get alist formandatory itemswhen doingproper macro work?


I'm shooting a 5DMKII & a 7D..... I'm guessing the 7D would be better for macro? Some of the creatures I want to shoot are shy. Will a 100mm be enough reach to get close enough to them? Which is best and why? .... macro lens or extension tubes?


Tell me more, please. I'm all eyes.


Mark

[neuroanatomist]

Mandatory? The only truly mandatory thing is some patience and a willingness to experiment! []


Seriously, though, you'll need some way to increase the magnification of your subject, and there are really three ways to do that:


1) a macro lens


2) extension tubes (between lens and camera)


3) close-up lenses (threaded onto the lens like a filter)


Technically, what defines macro is that the subject is projected at 1:1 (life-size) or greater onto the sensor. Of the three ways above, a marco lens will offer the most flexibility. The others are cheaper ways to approach macro, but usually don't make it to 1:1 magnification. Extension tubes eliminate the ability to focus to infinity, decrease the effective maximum aperture, and reduce the working distance (something to be avoided with shy critters); close-up lenses fix the focal length to a specific distance from the lens and decrease image quality. Extension tubes are most effective with shorter focal length lenses (50mm or less) but then working distances get pretty tight; close-up lenses work better with telephoto lenses.


The 7D will be better, not due to the effect sensor size on apparent focal length (working distance is the same on crop vs. FF) but due to the relatively greater depth of field (one of the challenges with macro shooting is that DOF decreases as the subject gets closer to the lens).


Another effect of the extremely shallow DOFs with macro shooting is that you'll likely want very small apertures to maximize DOF, meaning long exposures. So, you'll also need a good tripod, ideally with the ability to position the lens close to the ground (reversible or removable center column).


Once you've decided on a macro lens vs the other two options, the next choice is focal length. The longer the lens, the more working distance - important for shy critters. If you'll be shooting insects, I'd go with 100mm or 180mm. It also depends on the size of insects you'll be shooting. You may not need to go to 1:1 - butterflies, for example, are generally too big for that and you'll be at 1:2 - 1:4. For butterfly chasers, a telephoto like the EF 300mm f/4L IS USM with its 0.24x (~1:4) magnification is excellent, because you get that 1:4 magnification with a working distance of about 5 feet, compared to a couple of feet with a 100mm macro.


To get back to your requested list, what you really need to shoot macro is a macro lens and a good tripod. I have (and love) theEF 100mm f/2.8L Macro IS USM.

[Brendan7]

If you want to use your macro lens for more than macro, obviously the 100 IS is very nice. If all your subjects will be macro the Sigma 180mm is an excellent lens with IQ matching the Canon 180 at half the price.


Other helpful, but not mandatory items: macro twin lite flash (although a 430 EX will do just fine also), wimberley plamp, pheromone (to attract insects, some use this).


One mandatory item: tripod. Macro shots are often taken at f/11 and f/14 and low shutter speeds. A tripod that has a low minimum height (i.e. 5'') is best.


brendan

[Bombsight]

Thanks for all of the info.


I'm going to try the Canon tubes for now because Ineed a 16-35 II L for a new water housing on the way.... After that, I want an 85 1.2 II L ... So $$$ is tight for now.


I went with the Canon EF 25 II. Can this tube be used with just about any lens? I have a 100-400 L and a 24-105 L.
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[neuroanatomist]

I went with the Canon EF 25 II. Can this tube be used with just about any lens? I have a 100-400 L and a 24-105 L.
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Technically, yes. But, for example with the 25mm extension tube behind the 100-400 lens zoomed out to 400mm, you're not going to see significant magnification. With the 24-105mm, you can get to 0.61x magnification with the extension tube at the tele end; you can't use it at the wide end, since the focus point would actually need to be inside the lens (i.e. negative working distance).

[Jon Ruyle]

It can be used with any lens, but it won't do much for the longer ones.


For an ideal lens (ie, one that obeys the lensmakers equation), your magnification increases by (extension tube length) / (focal length). So, for example, at 400mm and a 25mm extension tube your maximum magnification increases by only 25/400 or 1/16. At 100mm your magnification increases by a substantial .25.


I don't think most canon lenses are ideal in this sense, but this is an okay approximation (at least in the cases I've measured).


Short focal length lenses respond more dramatically to extension tubes, but often do not have enough working distance to
take advantage of all this magnification. For example, if you try a
long extension tube with the 24-105 and turn the focus ring to focus as
close as possible, you might find the focal plane is inside the lens.

[Bombsight]

So the 24-105 would be my best choice ..... with it being well under 100mm?


How would a "nifty-fifty" work with the tube?

[neuroanatomist]

EF 50mm f/1.8 II, magnification factor 0.68-0.53x, working distance 99-120mm.
More details on some lenses (not the newer ones) with close-up lenses and 12/25mm tubes HERE.

[Jon Ruyle]

So the 24-105 would be my best choice ..... with it being well under 100mm?

Experiment and you'll see what works best for you. I actually use extension tubes more often with 100mm and above. I've gotten a fair amount of use of them with my 70-200 (even at 200mm, enough so that I have so far resisted the 180mm macro )


Just remember that with a zoom, you'll often get more magnification as you zoom out (opposite of how it is without extension tubes). So with my 70-200 if I want to make a butterfly or whatever bigger and don't want to add more extension, I can zoom out and move closer.

[Daniel Browning]

Could I get alist formandatory itemswhen doingproper macro work?

1. Lens
2. Camera
3. Having fun!

Good thing there are others here to give you real information. [] I would add that teleconverters are another method you can use to increase magnification. You might have one already.


I would also recommend the photomacrography forums.