In northern Arizona, the dirt roads can be nearly impassible. There used to be a saying about the roads that went something like this; choose your ruts because you are going to be in them for a long time. The same thing can be said about choosing a camera system, choose your camera brand because you are going to be in it for a long time. There are a bewildering number of camera manufacturers. In most large industrial manufacturing business the trend is to consolidation and fewer brand choices. In cameras, the trend is exactly the opposite. The number of manufacturers and camera models seem to increase every year.
Lately, the move has been to add cameras to smartphones and tablet computers. In some cases, these add-ons are sophisticated camera systems but some may also be of inferior quality to a dedicated camera. There are always a number of reviews online concerning the quality of the images from any particular camera system. My suggestion is to do the research before you buy. Search on the name of the camera and the word "review" and you will undoubtedly find someone with an opinion.
Genealogist almost always see the need for some kind of camera if only to record family events and people. But with today's electronic digital cameras, the camera has also become a tool for recording and digitizing documents and artifacts rather than just snapshots. Depending on your individual interests, finances and inclinations, you may be interested in taking quality photographs or satisfied with whatever the camera you have records. The good news is that very inexpensive cameras can take very good photographs. But unlike spending a lot of money on cars and clothes, cameras are tools and there is a reason why the professionals use certain types of cameras rather than others and why you might end up spending money for a better quality camera and lens system.
I have written about purchasing a camera in the past, but times change and cameras are partially electronic devices so the vast changes in technology have affected cameras as well as every other aspect of the electronics industry. Hence, there is a need from time to time to review the state of technology and update recommendations.
There are certain features of all digital cameras that determine the quality of the final image produced. I will briefly discuss the factors determining the quality of digital image produced by cameras in general, with a perspective on the importance of each.
A camera is essentially a light-tight box with a way to allow limited amounts of light to access and record the images on a light-sensitive substance. In the most extreme example, you can take recognizable pictures using a cardboard box with a pin hole and a sheet of photographic film. See Wikipedia: Pinhole camera. The first addition to this simple system is adding some kind of lens. The lens gathers the light and focuses it on the light sensitive substance (film or digital sensor). So, if I were going to rank the photographic components in order of the their importance, the most important part of the system is the lens.
Historically, cameras came with one fixed lens. Whatever limitations were inherent in the lens were unable to be corrected. Today there are a multitude of specialized lenses and computer software that can correct most, if not all, of their limitations.
In currently available digital cameras, the lenses can be extremely inexpensive or an individual lens can cost many thousands of dollars. Cameras are generally divided into two different classes: fixed lens cameras and removable lens cameras. If you have a camera in your smartphone, you have a fixed lens camera. You have to use the lens supplied with the camera. You can put additional lenses in front of the fixed lens, but ultimately, the quality of any image you obtain is determined by the quality of the lens.
Removable lens cameras allow you to change the lens for different photographic conditions. More expensive and/or professional level cameras can have a whole system of lenses for special circumstances. I mention both Canon and Nikon in the title to this post because both of these companies have a huge selection of camera models with an additional huge selection of lenses for their more expensive models.
You may be perfectly satisfied with the quality of the images you obtain from a smartphone (Android or iOS) but if not, there are a multitude of choices at every possible price level. Moving up a notch are the point-and-shoot cameras that are really sophisticated computers. You can buy a high quality camera for less than $100. You may wish to do some research online to see why you might want a more expensive camera. Websites such as Amazon.com have consumer reviews of almost every possible product.
If you plan on doing some very complicated photography, such as digitizing glass negatives, you might have to invest in some fairly expensive cameral equipment and some specialized lenses. These high-end cameras can cost many thousands of dollars and the lenses can cost more than the camera, much more.
Before you make a decision, realize that if you are buying a high-end digital single lens reflex (DSLR) you will likely have to stay with the same camera system for a long time because of the investment you have in lenses.