What is it?
Macro photography gets you closer to things, it makes small things larger on your sensor or film, by doing this it opens up the world of photography to things that you would walk past or miss on a daily basis. Insects flowers and many more things look amazing when you get closer to them than the naked eye. Here is what a macro lens and extension tubes can do for your photography.
A dedicated Macro lens will allow you to take pictures of objects, closer to the front of the lens than your kit lens. This allows you to get closer to your subject making it up to 5x its actual size on the sensor. A lens like the Canon 65mm MP-E Macro is dedicated to taking macro images and will focus on very short distances from the lens. But, that lens will only do that one thing, it does do it quite well though, but it is not as versatile as the Canon 100mm F2.8 Macro LIS this lens can be used to do portrait work as well as other things.
What if you wanted to learn about Macro photography but didn’t want to buy a macro lens just in case you tried it and really didn’t like it?
Extension tubes are your answer, they will convert almost any lens to do macro photography. A set set will cost you about $225 compared to the price of a dedicated macro lens that is great Value.
I have a set of Kenko extension tubes, they attach between your camera and lens, and move the lens forward. They come in a set of three, 12mm, 24mm, and 36mm and you can use one of them at a time or all three of them at the same time, they will allow you to focus closer to your subject using your existing lenses.
How do I use it on my camera?
I will be talking about how the ones I have work with my Canon camera and lenses. There may be some slight differences with other brands of cameras and extension tubes.
The set I have use a pass through system, there are contacts that allow the lens and camera to communicate with each other, so the camera will autofocus and set the aperture. You can buy units that do not pass through, they will require manual focusing and you cannot control the aperture, so you can only use the smallest number aperture that lens has, which will limit the depth of field in your photo, when shooting this close, you may need more depth, my advice is to buy the pass through models.
The focusing distance that a lens refers to is measured from the subject to the film or sensor it is being recorded on. A 18-55mm F3.5-5.6 kit lens that has a minimum focusing distance of 25cm, that means that your subject can be as close as 25cm from about the back of the camera.
As the tubes shorten the focusing distance on any lens they are fitted to, you do have to be careful of what you fit them to, as the focusing distance may be shorter than the lens, which would mean that the subject would never be able to be focused on. Wide angle lenses that focus close usually fall into this category, I have a Canon 16-35mm F2.8mm lens that has a minimum focus distance of 24cm, if I put a 12mm extension tube on that lens it cannot focus.
What does it do to my pictures?
Here are some examples taken back to back on a 50mm F1.4 lens with the 12mm 24mm and 36mm tubes and a 100mm Dedicated 1 to 1 Macro Lens, I have also added the tubes to the Macro lens to show what it would do to that lens. All the images were taken on a 5D mark II with ambient light at my desk, hand held and I was focusing on the 1:2.8 marking on the lens, the aperture was set to F2 and I was shooting at 1/250th when using the 50mm and F2.8 at 1/125th when using the 100mm Macro.
50mm with 12 mm tube: The photo on the left is the 50mm at standard focusing distance. The photo on the right is using the tube. Note the depth of field or out of focus in the background is starting to disappear very quickly.
50mm with 24mm tube: Note the out of focus is much more effective, and that the EF-S marking on the top of the lens is almost not readable.
50mm with 36mm tube: I now am so close that the EF-S marking is not in my picture. Note though that now the 60mm is starting to be out of focus. You can see the details in the gold ring and the rubber on the lens though quite nicely.
50mm with all three tubes: Note that with all three on the camera, I had to increase the exposure. Note the .8 of the 2.8 is now almost out of focus. The depth of field at this distance would be less than a millimetre.
100mm Macro: The photo on the left is the 100mm at standard focusing distance. The photo on the right is what the Macro lens can do without the use of an extension tube. This lens also has image stabilisation which can be handy when you are getting close and the smallest of movements will blur your photo.
I have added the 12mm tube to the 100mm dedicated macro lens to show that if you were to buy the tubes you can then still use them on your dedicated macro as well, and get even closer!
Here are some images that I have taken with a mixture of lenses with and without tubes. One of these images was taken with a dedicated macro lens. The first person to email me with the correct image and the image settings both aperture and shutter speed will win a set of extension tubes that suit their camera and a 2 hour photo walk around Roma Street Parklands showing how to use them.
Email me with your choice and the camera settings for your chance to win the tubes. I will announce the winner once it has been won.