Guide to DSLR Cameras and Settings | Core Controls Explained

A DSLR puts you in control of how every photo turns out, but the settings can feel overwhelming at first. Master just a handful of core controls—aperture, shutter speed, ISO, shooting mode, and a few setup choices—and you’ll start taking the pictures you actually want. This guide walks through each one with practical starting points, not theory. If you’re still choosing your first camera, our roundup of the best entry-level DSLRs can help you pick the right model.

The Exposure Triangle: Aperture, Shutter Speed, and ISO

These three settings work together to control both exposure and the final look of your image. Aperture controls depth of field and light intake—lower f-numbers like f/2.8 create a blurred background, while higher f-numbers like f/11 keep more of the scene sharp. Shutter speed controls motion blur: 1/1000s freezes action, while 1/2s blurs motion and works best on a tripod. ISO controls sensor sensitivity—lower ISO like 100 preserves image quality, and higher ISO lets you shoot in dim light but adds visible noise.

Change one setting, and you must adjust at least one of the others to maintain proper exposure. That balancing act is what photographers call the exposure triangle, and it’s the foundation of DSLR photography. Sensor size also plays a role: APS-C sensors, common in lower-cost DSLRs, produce a narrower field of view than full-frame sensors with the same lens, so factor that in when framing shots.

Shooting Modes and When to Use Them

The mode dial offers several options beyond full Auto. P (Program) automates exposure while letting you tweak other settings. A/Av (Aperture Priority) lets you set the aperture while the camera handles shutter speed and ISO—ideal for portraits where depth of field matters most. S/Tv (Shutter Priority) lets you set shutter speed while the camera adjusts aperture—great for sports and action where freezing motion is the goal. M (Manual) gives full control over all three exposure settings.

To shoot in Manual: choose an ISO appropriate for the light, decide whether depth of field or motion control matters more for your subject, set that priority first (aperture for depth-of-field control, shutter speed for motion), then adjust the remaining setting. Take a test shot and make small tweaks based on the result. Nikon bodies label these modes A and S; Canon uses Av and Tv.

Practical Starting Points for Common Scenes

For file setup, begin with RAW capture—choose Lossless Compressed if your camera offers it.

FAQs

What is the best DSLR setting for beginners?

Start with Aperture Priority mode (Av on Canon, A on Nikon). It lets you control depth of field while the camera handles shutter speed, making it the easiest way to learn how aperture affects your photos. Set ISO to 100 in good light, choose your aperture based on the scene, and let the camera manage the rest.

Should I shoot in RAW or JPEG?

RAW captures significantly more image data, giving you far more flexibility to adjust exposure, white balance, and detail during editing. JPEG files are smaller and ready to share immediately but discard data the camera deems unnecessary. For learning and maximum control, RAW is the better choice.

What does the exposure triangle mean?

The exposure triangle describes the relationship between aperture, shutter speed, and ISO. These three settings control how much light reaches the sensor and how the final image looks—including depth of field, motion blur, and visible noise. Changing one requires adjusting at least one of the others to maintain proper exposure.