Recently, while exploring some backcountry roads near Zion National Park in Utah, Mary and I encountered a small flock of black and white, long-necked grebes. We didn't have binoculars with us (we were in Utah for a predator shoot and wanted to reduce our luggage weight for flying) and we did not have a bird guide along, either. Largish, black-white, long-necked grebes can be one of two species -- a western grebe, or a Clark's grebe. I've been birding as long as I've been photographing, literally, and I'm always on the lookout for new species. I've seen several western grebes, and maybe even a Clark's before it was 'split' from the western and became a separate species, but I've never 'officially' seen one. Now, with an opportunity perhaps in hand, I wasn't equipted to know!
Of course, we did have our camera gear in our rented SUV and, fortunately, a borrowed Canon D30 digital camera. Luckily, I remembered this simple fact and I came up with the bright idea to simply take a digital photo of the birds, then, using the LCD monitor on the back of the camera, I could later compare the photo with an image from a bird guide. I had thought about taking notes, but I soon realized that I'd probably omit some key mark -- like whether the black cap on the grebe extended above the eyes, or included the eyes. Without a good reference, I knew I'd be frustrated in trying to ID the bird later, and without an accurate identification I couldn't 'count' the bird as a new species.
For my record shot I used a 400mm F2.8 with two 2X tele-converters stacked on top of each other. With a 35mm format that would give me 1600mm in focal length (400 X 2 = 800, 800 X 2 = 1600), but with the digital I'm also getting a 1.6X magnification, so that's 1600mm X 1.6 = 2,560mm of focal length, or about 51X magnification (based on a 50mm lens)!
With that much magnification it was extremely difficult to even find a swimming grebe in my viewfinder. Autofocus wasn't working so I had to manually focus, but I wasn't too concerned about award-winning images since I was just trying to get a record shot to help with identification. However, the one fairly sharp image truly astounded me with the quality -- I shot on a low image resolution (a small jpg file), used a tripod with a loose ball head, and manually focused, so there were a lot of variables that were not conductive to great quality. Yet the image was quite good, as this enlargement attests.
I wouldn't recommend this techneque for quality shooting, but obviously, if you do it right, you can get a pretty good image. This might be sufficient quality for a power point presentation off a computer, and certainly would be good enough to illustrate a newsletter or a web site. For birders, it might be just the ticket for getting a record shot that you can identify later, or to amass a whole collection of images for a personal bird file.
For Mary and I, however, the digital shot produced a disappointment. The grebe proved to be a western grebe, not the Clark's grebe I've yet to see. My life-lister species still eludes me!