Lord Foul wrote:Simple starter question...
These days you can get apparently good results from little digital cameras, phones, you name it. What are the benefits you actually get from a 'proper' camera (SLR etc), and do they really justify the extra cost?
I agree that for many people a good cell phone camera is just fine. However, there are a lot of things that you cannot do, or cannot do well with a cell phone camera. This may get rambly, so bear with me.
The most important difference between a cell phone camera and a "proper" DSLR or mirrorless camera is the size of the sensor. The sensor is the part of the camera that actually detects light and turns it into a photo. Cameras on cell phones have sensors that are extremely small, whereas the three most popular "proper" camera sensor sizes (Full Frame, APSC, and Micro Four-Thirds) are much larger. In some ways you can think of a sensor in a similar fashion to the pupils in your eyes. When it's really sunny outside, your pupils will contract so your eyes take in less light. When it's really dark, your pupils will get large and take in much more light. That's because the rods and cones in your eye only have a certain range of light in which they can properly function. The same thing holds true for cameras. A large sensor on a camera can operate effectively and produce beautiful photos in much
lower light conditions than a cell phone camera. When you go into bright light, you can adjust the aperture on a "proper" camera lens so it's smaller and lets less light through. You can also add something called a neutral density filter (or even a polarized filter) that acts like sunglasses for your camera lens. That gives you a lot of versatility as far as lighting conditions go.
There is a lot more
I could say on the topic of light and why you want more or less light going to your lens for various artistic or practical purposes, but suffice it to say that there are a lot of artistic things you can do with a proper camera that are impossible or highly impractical with a cell phone. The only one I'll get into right now, because it's usually the first thing people notice, is depth of field in portraits. A lot of people are into portraits and selfies these days. One of the effects you see a lot of people apply to their cell-phone shots is background blur. It turns out that with a proper camera, you can produce background blur in the original shot and it looks much more natural and attractive. I find fake background blur ugly, personally. People into photography frequently call the background blur you see in some photos due to a shallow depth of field "bokeh"...and the larger your sensor/aperture, the shallower the depth of field you can achieve and the better the bokeh will look. If you're interested in learning more about artistic use of time and light in photography that is only really possible on a real camera, I can get into them. Or, if you see any interesting shots online, I can probably tell you how they were done or explain the concepts behind them and if it's possible to do with a cell phone.
The second big difference between a cell phone camera and a proper camera is the availability of different lenses. A cell phone camera has a single lens and no zoom (with very few exceptions). If you think your camera phone is zooming, it's almost certainly just cropping your image before taking it, and therefore losing quality because it's not even using the entirety of its already-small sensor. You end up with a low-resolution image when "zooming" with a cell phone. With a proper camera, you can find lenses for all sorts of different purposes. Say you want to take photos of your child during a sporting event. You cannot get a good, close-up shot with a cell phone unless you're on the field. With a telephoto zoom lens, however, you can get photos that look like you were on the field even though you may have been very far away. I should warn you, though, that sports photography is very difficult (and/or expensive) from technical and gear perspectives. I can get into that more if anyone is interested.
Anyway, back to zoom/focal length. Beyond being able to make far away stuff look close, lenses have other effects on how a photo looks. You've probably seen photos that look very distorted, almost like they were taking from inside a fish bowl. That's because those photos were taken with what's called a fisheye lens. Fisheye lenses are the most "wide angle" lenses available, and they allow a camera to have a very "wide" field of view. Human FOV is about the same as putting a 45mm lens on a full frame camera or a 30mm lens on an APSC camera. That means that photos taken with those lenses will show the viewer basically what they would see if they stood in the exact same spot as the camera. Anything wider than that is considered wide angle. Wide angle is used a lot in real estate photography because you can "see" more of a room. However, the wider your shot gets, the more distortion it will have. That's why I mentioned fish eye lenses. As your focal distance gets shorter/FOV gets wider, your shot will have more of that fisheye effect.
Camera phones are all made with wide angle lenses because they allow you to take things like selfies and you can "zoom" if you want to take a shot of something further away (though I already explained the problems with that). There is software in the camera phone that adjusts the image to remove the fisheye effects, but it's not perfect. The same can be said of proper cameras and post-processing software like Lightroom. Anyway, you should not underestimate the effects of wide angle distortion on images, particularly portraits. Wide angle lenses basically take ugly portraits...I can link you to some examples if interested. Photographers with proper cameras will usually use lenses that are somewhere in the 80-100mm range for portrait work. Those focal lengths look good and have a mild slimming effect on the subject.
If you have any questions about what I wrote or want me to go into more detail on anything I alluded to, let me know