Tag: photography (page 1 of 4)

Holographic depth of field

Well this is cool. Although there are limited ways of refocusing a shot after taking it, this new method allows that to be taken to the next level using existing technologies. It could be useful for everything from smartphones to telescopes.

Essentially, scientists have developed a new imaging technique that captures two images simultaneously, one with a low depth of field and another with a high depth of field. Algorithms then combine these images to create a hybrid picture with adjustable depth of field while maintaining sharpness.

Smartphones and movie cameras might one day do what regular cameras now cannot—change the sharpness of any given object once it has been captured, without sacrificing picture quality. Scientists developed the trick from an exotic form of holography and from techniques developed for X-ray cameras used in outer space.


A critical aspect of any camera is its depth of field, the distance over which it can produce sharp images. Although modern cameras can adjust their depth of field before capturing a photo, they cannot tune the depth of field afterwards.

True, there are computational methods that can, to some extent, refocus slightly blurred features digitally. But it comes at a cost: “Previously sharp features become blurred,” says study senior author Vijayakumar Anand, an optical engineer at the University of Tartu in Estonia.

The new method requires no newly developed hardware, only conventional optics, “and therefore can be easily implemented in existing imaging technologies,” Anand says.


The new study combines recent advances in incoherent holography with a lensless approach to photography known as coded-aperture imaging.

An aperture can function as a lens. Indeed, the first camera was essentially a lightproof box with a pinhole-size hole in one side. The size of the resulting image depends on the distance between the scene and the pinhole. Coded-aperture imaging replaces the single opening of the pinhole camera with many openings, which results in many overlapping images. A computer can process them all to reconstruct a picture of a scene.


The new technique records two images simultaneously, one with a refractive lens, the other with a conical prism known as a refractive axicon. The lens has a low depth of field, whereas the axicon has a high depth of field.

Algorithms combine the images to create a hybrid picture for which the depth of field can be adjusted between that of the lens and that of the axicon. The algorithms preserve the highest image sharpness during such tuning.

Source: Impossible Photo Feat Now Possible Via Holography | IEEE Spectrum

The unintended consequences of photography

Some good points in this photo essay, including photography leading to greater compassion as well as political influence.

Photographs were more than just pictures. While the inventors never intended more than to capture an image, the medium turned into a social force with far-reaching effects.

Source: 5 Unintended Consequences of Photography | The Saturday Evening Post

The 2022 Drone Photo Awards

I had a conversation with my neighbour this week about drones. They were pointing out how invasive they can be, while I was talking about the amazing photographs they can take.

Sure enough, later that day I come across this year’s Drone Photo Award and there’s some absolute stunners in there. The ones of nature are, of course, amazing, but for some reason this one of a Dutch suburb grabbed me as my favourite.

The annual Drone Photo Awards announced its 2022 winners earlier this month, releasing a remarkable collection of images that frame the world’s most alluring landscapes from a rarely-seen view. This year’s contest garnered submissions from 2,624 participants hailing from 116 countries, and the aerial photos capture a vast array of life on Earth, including a caravan of camel shadows crossing the Arabian Desert, a waterlily harvest in West Bengal, and the veiny trails of lava emerging from a fissure near Iceland’s Fagradalsfjall volcano.

Source: From a Volcanic Fissure to a Waterlily Harvest, the 2022 Drone Photo Awards Captures Earth’s Stunning Sights from Above | Colossal