PatW
Contributor
I think we have to talk terms first.
SLRs are single lens reflex cameras that are film cameras. And those are not used much anymore.
DSLR is what I think you are talking about. That is digital single lens reflex. Instead of film the camera has an electronic sensor that records the shot onto a digital storage device like an SD card. That image can be loaded onto a computer and manipulated with photographic software. So this was a major advance. You could change your ISO while shooting. With film, you were stuck with what you had. Also, you can take as many images as your cards can store and your batteries could last. With film, you were limited to 36 shots.
Now there are mirrorless cameras. You do not look directly at the image through the lens like an SLR or DSLR. Instead the sensor examines the image and projects it onto a TV screen displayed on the back of the camera and or in the viewfinder. It used to be that the resolution of these screens was low and the electronics were slow making auto focus glacial. These problems have been largely surmounted. The mirror on the DSLR caused a certain minimum distance between the sensor and the rear of the lens. With a mirrorless camera, the rear of the lens is closer and this allows for the design of lenses that are faster (lower f stop) and with higher resolution. Both of those are good things. Because mirrorless cameras have intrinsic advantages over DSLRs, camera manufacturers are pretty much only designing mirrorless cameras in the future. Sure the Nikon D850 is still a nice functional camera but it is slowly falling behind.
Now the other thing is why not just shoot with phones? Well why not? The problem is phones have tiny sensors. Tiny sensors have issues that are intractable because the physics of light. Larger sensors on dedicated cameras will always produce better images.
But how much do you need? For most shots in good light, displayed on a low resolution format like facebook, phones work great, For low light or high resolution photography, full frame cameras are superior, And medium format cameras with even larger sensors have an edge over full frame in certain circumstances. A problem medium format has is if you want a long lens for wildlife or sport it will be ENORMOUS and cost $$$$$$$$. So forget that.
SLRs are single lens reflex cameras that are film cameras. And those are not used much anymore.
DSLR is what I think you are talking about. That is digital single lens reflex. Instead of film the camera has an electronic sensor that records the shot onto a digital storage device like an SD card. That image can be loaded onto a computer and manipulated with photographic software. So this was a major advance. You could change your ISO while shooting. With film, you were stuck with what you had. Also, you can take as many images as your cards can store and your batteries could last. With film, you were limited to 36 shots.
Now there are mirrorless cameras. You do not look directly at the image through the lens like an SLR or DSLR. Instead the sensor examines the image and projects it onto a TV screen displayed on the back of the camera and or in the viewfinder. It used to be that the resolution of these screens was low and the electronics were slow making auto focus glacial. These problems have been largely surmounted. The mirror on the DSLR caused a certain minimum distance between the sensor and the rear of the lens. With a mirrorless camera, the rear of the lens is closer and this allows for the design of lenses that are faster (lower f stop) and with higher resolution. Both of those are good things. Because mirrorless cameras have intrinsic advantages over DSLRs, camera manufacturers are pretty much only designing mirrorless cameras in the future. Sure the Nikon D850 is still a nice functional camera but it is slowly falling behind.
Now the other thing is why not just shoot with phones? Well why not? The problem is phones have tiny sensors. Tiny sensors have issues that are intractable because the physics of light. Larger sensors on dedicated cameras will always produce better images.
But how much do you need? For most shots in good light, displayed on a low resolution format like facebook, phones work great, For low light or high resolution photography, full frame cameras are superior, And medium format cameras with even larger sensors have an edge over full frame in certain circumstances. A problem medium format has is if you want a long lens for wildlife or sport it will be ENORMOUS and cost $$$$$$$$. So forget that.