Song Sparrow, I think

I walked along Battle Creek west of Hermosa this afternoon, practicing with a new lens. I bought a Sigma 400mm mirror lens (short and fat with a big plastic disc in the center of the front glass) for $150 on eBay, and a 2x converter for $25, resulting in 800mm of magnification (roughly 24x if you compare it to binoculars or a scope).

These shots (the sparrow) were from a distance of around 90 feet, give or take 20 feet. 60%-70% of the frame is cropped out. I shot at 1/500-sec. or faster. The lens has a constant aperture of f5.6; the doubler reduces that to f11, so light could be a problem later than 4pm or when the sun goes behind a cloud. These were shot earlier, in bright sunlight or lightly hazed sunlight. The sparrow is in shadow, so I bumped the contrast a little in PhotoShop.

I'm pretty satisfied with the results. I always want more resolution (which usually translates to sharper photos), but this is much better than using a sharper 200mm lens with a doubler (making it 400mm) and then enlarging a smaller portion of the frame. I was using a monopod or freeholding the camera. I lost lots of frames to camera shake. I wonder how much sharper a $2000 600mm lens is, hmmm....