Starting off with my new (to me–it’s actually about 12 years old) Nikon D70S and a Sigma 17-70mm F2.8-4 DC Macro lens, I decided to try out extension tubes. I bought a set of three Fotodiox extension tubes for $15. The set includes 7mm, 14mm, and 28mm, stacking together for a total 48mm. Basically, the extension tubes sit between the camera and the lens.
Here is a photo of the camera with the lens and the full stack of extension tubes:
The initial problem with this setup is that you (a) lose tons and tons of light, (b) lose the ability to autofocus, and (c) lose the ability to tweak your aperture.
My strategy for overcoming this had to be simple: reduce movement and increase light!
First, I rested the camera on a disk. Then I turned off the autofocus on both the camera and the lens. Then I zoomed the lens all the way in and positioned the object I’m photographing so that it is just under a inch away from the subject. Then I turned off the flash and figured out an external light source. Sometimes I used an overhead lamp. Sometimes I used the flashlight app on my phone. Sometimes I used both. I experimented pointing my phone light at different angles for different results and different shadow configurations. Then I manually focused and shot away!
I’m very happy with the result. I estimate that I get almost twice as much magnification with the $15 tubes! Objects that are in reality 1 cm appear in my images well over 20cm long. What I lose is photo quality and I have to with external lighting and obsessively remove movement.
I look forward to warmer weather and a chance to try this setup out on invertebrates. For various reasons, this setup is not very practical for field work. However, I’m hopeful that it will be very helpful in getting better macro photos of invertebrates.
Here are some links to some of my tests on Flickr:
“Coelius Secundus Curio wrote a book of eighty-eight pages which was published in Basle in 1544. The name of his book, , shows that it was in effect a sermon, Curio took his facts, both true and false, from the writings of Pliny and interpreted the life and work of spiders as evidence of the wisdom and goodness of the Creator.” – Theodore H. Savory in Spiders, Men, and Scorpions: Being the History of Arachnology, 30 (University of London Press, 1961).
The treatise mentioned by Savory, which was the first work ever exclusively devoted to spiders, begins on page 52 of this document. Curio (1503-1569) was an Protestant Italian living in exile in Switzerland. According to Robert Baird in Sketches of Protestantism in Italy, Curio was “the most regretted loss” of those who left Italy for the sake of Protestantism.
“The arachnologist W. S. Bristowe calculated in the 1930s that, at certain seasons, a meadow in south-east England may contain more than two million spiders to the acre.” – Paul Hillyard, The Private Life of Spiders, 13