I had an ordinary optical "200x" microscope and saw a few shaky, interesting things in a drop of water on a glass slide, I but had no good way to take a photo. Holding a digital camera up to the eyepiece was problematic at best. I'd heard of USB microscopes that connected to a PC, such as the QX3. Checking the reviews on Amazon quickly dissuaded me from that. Then I found the Celestron 44340. It had a built-in 2MP digital camera. Images were saved to internal memory and transferred to the PC via USB cable, or to a SD card. I was also concerned about getting good images. In books like Guide to Microlife
(ISBN 0-531-11266-7), there were excellent photos in darkfield illumination, as well as the usual brightfield. The Celestron 44340 did both, although darkfield only worked at the 4x and 10x objectives. I got a set of glass slides, glass cover slips, some depression slides, eyedroppers, and containers. After the summer rains, there were many places to collect samples, as well as from shorelines of rivers and lakes. I was able to successfully image in brightfield and darkfield rotifers, amoebas, flatworms, copepods, ostracods, shrimp hatchlings, vorticella, bursaria, diatoms and algae, and a variety of fast-moving ciliates. In addition to digital photos of up to 2 megapixels in size, I also recorded movies of a few seconds to a few minutes, sometimes switching between 4x magnification to 10x or 40x to get more details, and even switching between brightfield and darkfield. If I found something interesting, I could use software to extract a still image. The only CON I can think of is that when the microscope is turned off then back on, the internal date and time resets to 1/9/2031 8:00 PM, so any photos or movies taken all have that date, unless you manually set it every time.