Friday, November 25, 2011
Helpful Monitoring Accessories
At the beginning of the summer, I got supplied with the usual set of monitoring supplies: Clipboard, Thermometer, Refractometer, Collection Trays, and a Pocket 6X Magnifying Glass. I was all set, but when I arrived out in the field, the 6X magnification left me poorly equipped to make species determinations of the colonial species, and it was also difficult to distinguish the red bryozoan Bugula neritina from some filamentous red algae. Back at home, under the stereomicroscope, I could easily make species determinations magnifying specimens 20-40X. It was then that I realized I needed magnifiers at this range of magnification.
Off I went to the internet and found a terrific line of magnifiers at Amazon. I purchased several, but the jeweler's loupes were the most helpful. Some magnifiers are made for viewing details of photographs and the plane of focus is right against the glass, but the jeweler's loupes are designed to be held away from the subject and this feature keeps the lens clean and dry in the field.
30X Jeweler's Loupe Magnifying Glass
The 20X, 30X, and 40X lenses are now permanent supplies in my monitoring bag; however I'd say that I use the 30X lens the most. I use the 20X when I need a wider field of view and the 40X for the smallest details. Nonetheless, I've used all of them on my most recent trips.
Don't depend on these magnifying glasses to help much in image documentation, however. Feeling in an adventurous spirit, I tried taking an iPhone photo of a small Botryllus schlosseri colony growing on Ulva. I held the 30X jeweler's loupe lens directly against the iPhone lens, and surprisingly, I was able to obtain focus through the lens. However, I could not hold the specimen or camera steady enough to take a sharp, in-focus photo. My best attempt is shown below - not bad for evidence but insufficient for documentation. At least the Botryllus was fresh!
A Blurry Botryllus schlosseri growing on Ulva Sea Lettuce
Photo taken with a 30X jeweler's loupe held directly against the camera lens
of an iPhone mobile device. Time to get a macro camera........
Posted by Thomas Ermak