Cancún is a photographer's dream of turquoise water, white sand and big skies. The Caribbean changes color with the depth and the light, from pale aqua over the sandbars to deep blue offshore, and the Nichupté lagoon behind the Hotel Zone turns gold and pink at sunset.
Add Maya ruins with iguanas, the underwater sculptures of the MUSA, the colorful streets of Isla Mujeres and the light beams of the cenotes, and you have a full trip of images.
The light is the key. The eastern beaches face the sunrise, so early mornings bring soft light and empty sand, while the lagoon faces west for sunset. Midday sun is harsh but shows the water at its most turquoise, especially from a height.
In summer, sargassum can change the look of some beaches, so check conditions and keep alternatives in mind.