A photographer’s adage is the best camera is the one you have with you. Since most journalists have a mobile phone with them at all times, it can often be the default option for capturing images and video while on an assignment.

However, professional photographers carry a ton of equipment and it’s not because they need the cardio. The various lenses, camera bodies and ancillary equipment can make a difference between a great shot and a lousy one.

Tim Gleason, a professor of journalism at UW-Oshkosh and an award-winning former news photographer, often has to patiently explain to students (and some faculty members) why the sentence, “I have an iPhone, so I’m a photographer” isn’t accurate. Tim was gracious enough to give us the top five reasons a professional set of photography equipment is superior to a point-and-click smartphone camera:

1. Cell phones have smaller sensors that have less dynamic range—the ability to record details in highlight and shadow areas. The so-called “megapixel race” means manufacturers are putting more megapixels (think of millions of mini cameras on a sensor), but the dimensions of the sensors don’t grow in proportion to the increase in megapixels. Interchangeable lens cameras (ILCs) like digital single-lens reflex cameras (DSLRs) and mirrorless models have larger sensors so those mini cameras that gather light can be larger and better at gathering light.
2. Most cell phones rely on “digital zooms” that don’t zoom at all. A true zoom lens has internal lens elements that move into different positions, which makes the subject larger or smaller.  Cell phones’ digital zoom is simply a crop of the picture. An optical zoom is the only true zoom. Cropping and enlarging an image will reduce its quality, possibly to the point of not making it publishable.
3. Cell phones are notoriously easy to move while taking a picture or video. They are comparatively lightweight, so it is easy to move the camera while taking a picture. This results in a blurry image. ILCs are designed to be held for comfort, and their build (weight and dimensions) helps to avoid camera shake while taking the picture.
4. Any camera works best with average daylight scenes. However, much of life occurs outside of the ideal scenario. This is when cell phones have trouble. Most cannot have their shutter speeds, apertures and ISO (sensor sensitivity rating) manually changed to specific settings. While some apps enable these changes, the cell phones do not have the full range of controls of ILCs.
5. Cell phone manufacturers were ahead of ILCs in video development, but the ILCs have caught up. Not only is 4K readily available albeit it rarely needed, ILCs are now offering more video settings to control, accessories for video production that work more naturally with ILCs than the small cell phones, and better image quality because of those larger sensors.