So you want to do your own product/food/lifestyle photography. You have been using your cell phone, but are thinking about moving onto something better. Do you need a fancy expensive camera? Not unless you plan on printing billboards. Any entry level DSLR will do these days - save some more money and buy used.
Sample photo essentials: Nikon D7100 cropped sensor DSLR, with a 50mm f1.8 lens, a wireless remote, polarizing filter, and a sturdy Manfrotto tripod.
What makes a good photograph, aside from talent for visual communication, is a combination of having a decent sensor, good light, and a decent lens. You already have the styling and framing knowledge, and are willing to invest in an Intro to DSLR course if you don’t already know that stuff, too.
Let’s quickly talk about megapixels. Your cell phone camera and any entry level DSLR out there have enough megapixels. Don’t worry about that for web quality photography. But the quality of those pixels differs based on the size and quality of the camera sensor. Tiny sensors don’t record as much light information into their ‘pixels’, resulting in more noise, and less colour range. The bigger the sensor - the more opportunity light differences hitting it have to record a better, clearer, less noisy photograph. If you recall the Flintstones' camera - a bird inside a box drawing what it sees - the sensor size would be equivalent to the size of the stone tablet it uses to create the image. The bigger the stone - the more details the bird has the ability to record. Of course, all kinds of technological mumbo jumbo can follow here about the intricacies of sensor quality, but you probably don’t need to know about all of that at this point.
Let’s just look at the sensor size of three cameras - a typical cell phone camera, a cropped sensor (most entry level DSLRs), and a full frame (the more expensive DSLRs). The biggest one measures at 24mm x 36mm actual physical size. As you can see, the jump from cell phone to cropped sensor (also labelled APS-C, for Advanced Photo System type-C) is quite significant. The price difference to jump from APS-C to full frame, though, can be too much, and I am suggesting that you don’t need it for simple web content creation. In fact, lots of professional photographers use cropped sensor cameras. (Side note: APS-C sensor sizes vary slightly from brand to brand, and there are subtypes.)
Finally, you need a good lens. The kit lenses sold with DSLRs tend to be pretty lame. As a starting point, I suggest you find yourself a 50mm f1.8 lens made for a full frame camera, but which you can still put on your cropped sensor entry DSLR. Because of the sensor difference, that means the 50mm lens acts more like a 75-80mm lens, which is a better range to shoot product. The 50mm lenses are cheap, so it works out in your favour. Having it f1.8 means you will be able to have a shallow depth of field, too, so you can make your backgrounds all blurry, like a pro. Another good reason to switch away from a cell phone. Note that this is NOT a zoom lens, it is called a prime lens. Primes tend to be better. Also, zooms that can shoot at f1.8 are… super expensive.
What else do you need? A tripod, a remote control to eliminate camera shake, a polarizing filter to minimize reflections, and a few white foam cards to help bounce light onto your subject and soften shadows. You can buy the foam cards from the dollar store.
In summary, get any entry level DSLR made in the last 2-3 years - feel free to find it used. Find a 50mm f1.8 lens made for full frame cameras; can also find used or buy new for about $150. Then look at the diameter of the actual lens (it should say on it, 52mm or something like that), and order yourself a polarizing filter online in that size. Order a remote control that will work with your specific camera model, and has good reviews (sometimes knock offs are crap). Personally, I have used the Nikon D7100 cropped sensor camera and can recommend it as an excellent choice. You can find it for around $500+ used. Any reasonably solid tripod will do - another thing you can look for used. Dollar store for white foam cards - in the poster section.
All of the above is 100% purely my very own personal opinion and suggestions. If you are not sure this applies to your needs - do ask! If you have a specific question for some other aspect of doing your own photography at home - do ask, so that I know what topic to write about next :) Share with anyone you think may find this useful.