Changes in Istanbul Seascape from Morning to Afternoon

July 13, 2020

MarioFreitas-March-30-2020a

MarioFreitas-March-30-2020b

Photographer: Mario Freitas 
Summary Author: Mario Freitas 

Effects of daylight on the field of view depend strongly on the angle of incidence of sunbeams relative to the observer. Shown above are a pair of photos depicting the famous islet where lies Maiden's Tower in Istanbul, Turkey. Both pictures were taken facing east, but at different times of the same, early spring day. They were taken from a cruise I took across the Bosporus Strait.

In the morning sunlight, I was blinded by bright sunbeams reflecting off the rippled water. Rays were refracted by the ripples as well, but their contribution was quite weak. The tower displays a low-contrasting silhouette against the Asian coast of Bosporus, almost like a monochrome picture.

When we cruised past near the same point 6 hours later, afternoon sunbeams and their reflections were coming from the western sky, at my back. Now, the refracted rays, undergoing Rayleigh scattering, makes the water appear in hues of deep blue. Shadows on the tower walls allow a better view of its architectural style

The original Maiden's Tower (Kız Kulesi in Turkish) dates from the medieval Byzantine era, around 340 BCE. It was destroyed and reconstructed several times during its long history, which involves a number of classical legends. Nowadays, the tower is home to a museum with a cafe having a panoramic view of the Bosporus. Photos taken on March 31, 2006.

Photo Details: Top - Camera Canon PowerShot A520; Software ACD Systems Digital Imaging; Exposure Time 0.0008s (1/1250); Aperture ƒ/8.0; Focal Length 23.2mm. Bottom - same except: Exposure Time 0.0020s (1/500); Aperture ƒ/5.5.