Close-up photography: Getting close to your subject
Several ways of getting close
You've probably heard the expression "There's more than one way to skin a cat"; well the same thing can be said for close-up photography. There are so many ways to get close to your subject that you'll probably be able to use things you already have in your camera bag to get the job done.
First of all, let's define some terms and start off with a common language. One term is life-size. What this refers to is the size of the subject on 35mm film. Life size on film means that if you take your slide (or negative) and place it next to the actual subject, the subject on film and the real subject will be the same size. Half life-size means that the subject on the film is 1/2 the size of the real subject. Twice life size....well, I think you get it.
These terms are also sometimes referred to as magnification ratios. A ratio of 1:1 is the same as life-size. A ratio of 1:2 means half life-size, 1:4 is 1/4 life-size. 2:1 is twice life size.
These ratios are often engraved or imprinted on the focusing scales of some macro lenses. 1:1 stands for life size. 1:2 means one-half life size. If you're shooting 35mm film or using a DSLR with a full frame (FX) sensor, these ratios still hold true.
But if you're using a camera with a DX sensor then these ratios don't hold. A 1:1 marking on a Nikkor 105mm micro lens will yield an image that's 1.5x life-size.
Understanding these terms will make the concepts of close-up photography easier to grasp.
(As mentioned, with digital, it gets a little bit more complicated, what with all the different crop factors out there. Suffice it to say, if you use the techniques described below, just multiply the magnification by your camera's crop factor to end up with total magnification for your camera.)
So let's look at a few ways of getting closer.
When a lens focuses, it's really moving the glass back and forth, the farther away the lens is from the camera body, the closer you can focus. So by adding extension tubes, you essentially "extend" the focusing range of the lens, allowing you to focus closer to your subject. Extension tubes are, as the name implies, just tubes; there's no glass in them at all. You will loose light however, the more extension the greater the light loss. For example, A 50 mm tube will cost you about 1 1/2 stops of light.
To determine the magnification you'll get by using extension, use the following formula:
Extension divided by focal length equals magnification. Or in the case of a DX camera, extension divided by focal length then multiplied by the crop factor of the sensor.
For 35mm film or full frame sensors, a 50 mm extension tube on a standard 100 mm lens will yield a magnification ratio of 1:2, or 1/2 life-size. A 50 mm extension on a 50 mm lens will yield 1:1, or life size on film. So more extension means more magnification. For instance, 75 mm of extension on a 50 mm lens yields 1.5x life size on film. Any lens will focus closer with extension.
These lenses yield the best quality but at a high price. Typical focal lengths are in the 50 to 60 mm range, the 80 to 105 mm range, and the 180 to 200 mm range. There are also some true macro zooms like the Nikon 70-180 mm zoom (sadly no longer available. but you might find one on eBay).
As the focal length increases, so does the price; a typical 105 mm macro lens from the major manufacturers will run about $600 or more.
As the focal length increases so does the working distance. With a 200 mm macro you'll be about twice as far from your subject than if you were using a 100 mm macro, for the same image size. As the focal length increases, background coverage decreases; you'll have better background control. A 200 mm lens will have a narrower angle of view than a 100 mm lens. See this lesson for an example.
Many newer micro/macro lenses will focus to 1:1 all by themselves because they have built in extension. Some will focus to 1:2 but require an extension tube to get to life size.
For ease of use and greater stability, lenses with built in tripod collars (usually the 200 mm range) are a great benefit.
Zoom lens macro setting:
Many zoom lenses will have a "macro" setting. This setting is usually limited to around 1:4 magnification (1/4 life size). As mentioned, there are some true macro zooms.
Using extension with a zoom lens:
As stated before, any lens will focus closer with extension. This applies to zoom lenses as well. Using an extension tube (or two, or three...) will allow you to create some very high quality close-ups. This option is a little awkward to use however. Every time you zoom in or out you'll change your magnification ratio. Your focus point will also change. When you change focus you actually change extension too. So every time you refocus your magnification will change slightly. You'll end up working in a back and forth manner; changing one parameter will change another.
Two-element close up lenses: (not to be confused with micro/macro lenses).
These accessories screw into the filter thread of the lens, just like a filter. Only they're not filters, they're magnifiers. For the money and quality, this is probably the best way to go. Close up lenses are usually used in conjunction with zoom lenses in the range of 70-300. By stacking these little wonders, magnifications of 1:1 or better may be achieved. They may also be used on micro/macro lenses to increase magnification. One great advantage these have over extension tubes is that they exhibit no light loss.
Be sure to get the quality two-element close up lenses, like those made by Nikon or Canon, the single element close-up lens sets sold by some filter manufacturers will do the job, but not with the same quality.
Here are the designations for the Nikon and Canon close-up lenses:
3T and 4T have filter thread size of 52 mm. 4T is stronger. $30-35
5T and 6T have filter thread size of 62 mm. 6T is stronger. $45-50
3T and 5T are rated at 1.5 diopters
4T and 6T are rated at 2.9 diopters (if that means anything to you)
(Note: the Nikon close-up lenses are getting harder and harder to find as Nikon doesn't make them any more. You might be able to find them on eBay)
250D ("D" stands for "Dual" element): Designed for lenses in the 30-135 mm range
500D: Designed for lenses in the 70-300 mm range.
The canon close up lenses come in filter thread sizes of 52 mm, 58 mm for the 250D and 52 mm, 58 mm, 72 mm and 77 mm for the 500D. Prices range from about $70-140. Canon also makes single element close up lenses for less money ($30 to about $80) but they are of less quality.
These two-element close up lenses placed in front of a medium to telephoto zoom (70-210, 80-200, 70-300...) make for a convenient, light, and compact close up system. Because they are of such high quality, the quality of your image will be mostly limited to the quality of your main lens and your photographic technique. They're easy to use and produce good results. This is the easiest and least expensive way to get into close up photography.
Using these in the field will take a little bit of practice. You'll need to get closer to your subject but once you've got something in focus, you'll be able to zoom in or out, only needing to slightly touch up the focus. Put one of these on your zoom lens, you'll quickly get hooked.
Some other options:
Use this formula to determine magnification: (Prime lens/stacked lens) x Crop Factor = magnification.
If you have a 100 mm prime lens (mounted on the camera body) and stack a 50 mm lens, the magnification will be 100 mm/50 mm = 2, or twice life size on film or full frame (FX) sensor. Stack a 24 mm lens on the same 100 mm prime lens and you'll end up with 4 times life size on film! Control aperture with prime lens. Stacked lens should be set at widest aperture setting. Use a "stacking ring" to connect lenses. This is just a ring with filter threads on both sides so you'll end up with two lenses "face to face".
Reversing a lens on the camera body:
Reverse mount rings are available for the different manufacturers' cameras (Nikon, Canon, etc.). The mounting ring screws into the filter threads on lens, and the other side mounts onto the camera body. You'll be able to get closer, but be careful you don't touch the rear element of the lens with your subject. Reversing a 50 mm lens will yield approximately 1/2 life-size (an area of about 2x3 inches)
Teleconverters won't get you any closer but they will magnify what you already have. They won't fit on all lenses (usually matched for certain lenses in a manufacturer's lens line) but will usually fit on extension tubes. 1.4x converters will cost 1 stop of light and 2x converters will cost 2 stops.
Mix and match:
You can combine your equipment to achieve different results. If combining extension tubes and teleconverters, place the teleconverter behind the extension tube, this will yield the most magnification.
For example: If using a 300 mm lens attached to a 50 mm extension and a 1.4x teleconverter behind that, you'll be able to photograph 1/4 life-size, or an area of 4x6 inches:
(50 mm extension /300 mm focal length= 1/6 life size (0.166x). Add the 1.4x converter and you'll end up with 1.4 X 0.166 = .23, or 1/4 life size.)
By using the same equipment and swapping the extension tube and teleconverter:
300 mm x 1.4 = 420 mm. 50 mm extension /420 mm = .12, or about 1/10 life-size, which is an area of about 10x15 inches.
So, for the greatest magnification attach the extension tube to the lens and the teleconverter to the extension tube:
lens | tube | converter | camera body
This should get you started in the world of close up photography. For more, read my article on close up techniques.
Recommended reading: John Shaw's Close Ups in Nature