I am going through old backup hard drives to cleanup and remove files that are not needed. I found a few images of Ospreys from a local Nature Reserve taken many years ago near my old home. I was using a 400mm lens, but with the 1.5 crop camera, the Field of View was equal to using a 600mm lens. These were from very early digital cameras, a Nikon D1x (2001, 5.3 megapixel) and Fujifilm S2 Pro (2002, 6 megapixel). I also used before these a Kodak DCS1, a modified Canon EOS-1D (1995), with a 6 megapixel sensor, but had no preview and used PCMCIA cards. The DCS1 used special Kodak software to process the digital B&W raw files to color. Very strange system to use, but it was the beginning of digital photography as we know. It is interesting to see how far and good digital imagery has come! But your cell phone probably produces a better file than these early cameras.
Kodak DCS1 (1995 ~$20,000)