On a recent Friday morning, Jason Powell went to the Capitol to photograph not the politicians, the architecture or even the tourists. He went to photograph a photograph.

The scene taking a second turn in front of the lens was one worth revisiting 70 years later: a bevy of beautiful California girls dressed to represent the state’s fruit crops. They smiled from the Capitol steps, in a photo discovered in the recesses of the Library of Congress online photo archive. The caption identified them as a “cornucopia” participating in a 1939 publicity event with Sen. Sheridan Downey to spur the construction of a highway from San Diego. Powell printed it, took it to the Capitol and stood there amid tourist commotion, trying to figure out exactly where those California beauties posed.

Powell’s photo in a photo is also a moment within a moment. It’s his way of briefly connecting what was captured in the milliseconds of a camera’s aperture opening decades ago with the place it happened in the present day. For his Web photo series “Looking Into the Past,” Powell takes his photographs of photographs with a wide-angle lens so that when he holds up a photo from years ago, his camera takes in the present-day setting as well. When he’s able to perfectly align the image with the contemporary scene, it’s either a neat parlor trick, a portal through time or both. His work has gone viral on Reddit, Digg and other social media sites.

“I’m the type of person who would walk down the street and wonder what it was like 100 years ago,” Powell says. “This is how I do it.”

Powell, who lives in Reston, began his photographic time travel unintentionally, in February 2009. He had planned to do a typical then-and-now diptych with Library of Congress images of Leesburg, but when he held the image in front of his camera to check his perspective, he had the idea to just keep the photo there.

Since then, Powell has juxtaposed 1920s automobiles at the Loudoun County Courthouse with present-day sedans zipping by. He has posed horse-drawn buggies precariously close to crossing the double yellow line of a Warrenton, Va., road, and he has placed a photo of suffragettes at the White House, appearing to block the path of present-day tourists.

The most interesting thing about his photos isn’t seeing what has changed — it’s seeing what has stayed the same. Some of the trees in his photos are the same ones from decades ago, only taller and stronger. Statues in traffic circles, unaltered, are a reminder of the permanence of monuments in a rapidly changing urban landscape. Although some buildings remain (with new occupants — the Mary Surratt House is now a Chinese restaurant), many have been replaced with the wearying office buildings that fill so many blocks in the District.

“It makes me very sad,” Powell wrote in a caption for a photo of four buildings with ornate facades taken on Ninth Street in 1922, which is held up to a present-day office building that replaced them. “I want to step into this photograph and go join those folks in line. I want to eat at the Acropolis Cafe. I want to visit the Gayety. . . . You cannot convince me that Washington, D.C., is better off by having the modern blahbuilding taking up this space instead.”

In the era of the present-day blahbuilding, there’s also contemporary blahphotography. The improvement of cellphone cameras means that anyone who owns an iPhone can fancy himself a photographer, but the images captured often lack the charm and visual interest that antique photos have. Although more photos are being taken than ever before, many are uninspired.

That’s why vintage photography — or simulated digital imitations — is getting a second look in projects such as Powell’s.

Shorpy, a straightforward curated site of historic photos from the Library of Congress, was one of the first. It’s run by Dave Hall, a former copy editor for The Washington Post. The site My Daguerreotype Boyfriend has examined the attractiveness of gentlemen from bygone eras, and Awkward Family Photos has specialized in collecting Olan Mills shots from the 1980s.

Photographer Irina Werning’s “Back to the Future” photo series puts adults in the same poses and outfits of their side-by-side childhood shots. Historypin geotags the location where old photos were taken; when users upload them, a visitor can look at historic images of the real-life scene before them. And Instagram and Hipstamatic, two iPhone camera apps, make any image shot with an iPhone look as if it were taken on a vintage camera instead.

Photographer Jason Powell takes a photo using an historic picture at the Capitol. (Bill O'Leary/WASHINGTON POST)

The sites that don’t cull from readers’ personal photos rely heavily on the Library of Congress’s online catalogue, which contains hundreds of thousands of images. Many of these photos are old enough that their copyright has expired, giving artists, historians, filmmakers and anyone else free rein to use them. Beverly Brannan, curator of documentary photography, says the library does not officially keep tabs on the sites that use the photos, but she’s a fan of sites such as Looking Into the Past and My Daguerreotype Boyfriend.

“It seems to me that lots of people don’t have a good sense of history anymore, so to bring these pictures to people’s attention and to discuss them with facts, and put them in context, it’s very educational in a painless way,” Brannan says. “We think it’s a really interesting way to do research, to see quickly how things used to look and how they look now. I think all of us are history buffs, and we really enjoy this way of going back in time, going forward in time and learning more about what we’re seeing.”

Powell didn’t invent the photo-within-a-photo technique: Archaeologists, who call it “Prince’s Principle,” have been using it to document changes in historic sites. Taylor Jones didn’t know that when he took his first photo-within-a-photo in May, after finding a photo of his younger brother at the same kitchen table where Jones was sitting. But in the three months since, his Web site, Dear Photograph, has become a viral sensation. He recently signed a book deal with HarperCollins. His site reflects a nostalgia for film from a generation of photographers that has grown up shooting primarily digital.

“I think because everything’s becoming so digital now, that physical photographs — actual pictures — are so cool to look at,” Jones says. “It’s the fascination that people have with old trends becoming new . . . we wish we could live in that old age when there wasn’t any technology.”

Jones, 22, says this wistfully, but it’s hard to believe he means it: Because of digital technology, he was able to capture these images, and because of the Internet, he was able to share them. And when he’s not working on Dear Photograph, he’s a social media manager for a technology company in Waterloo, Ontario.

“It’s ironic, but it’s using digital electronics to give people a window into the past, so it works out,” he says.

Jones’s and Powell’s sites are also collaborative, encouraging others to submit their photos to the site or to Flickr. Ivan Sciupac, a 36-year-old D.C. “iPhoneographer” who blogs at Here’s Looking at Euclid, has attempted a few Looking Into the Past/Dear Photograph shots of the city from photos of a childhood vacation in Washington.

“When you see a photo of someone from a different time, and you can be in that spot, you can connect with that scene or that setting or that person,” Sciupac says. “It makes us feel good. It’s human instinct to be nostalgic.”

Sciupac shoots street portraits of his neighbors in Adams Morgan on a digital single-lens reflex camera but does much of his work with an iPhone. Although he occasionally shoots film — even with a Holga, one of the vintage cameras that the iPhone apps emulate — he says taking photos on his phone is easier.

“I don’t think it will be a passing fad, and if it does go away, it will be a while,” Sciupac says. “It’s a lot more work to take film shots, and it’s a lot easier to re-create that. The thing is that these camera apps like Instagram and Hipstamatic, they do a good job, and you also have high-quality shots.”

Powell has played around with Hipstamatic and Instagram, but he eschews fake vintage-effect photography for authentic antique photos. As he browses through his stack of potential shots, he pulls out photos of a Charleston dancing demonstration on the railing of the Cannon House Office Building, some Boy Scouts from Venezuela and “the world’s tallest cowboy with the world’s shortest something-or-other,” he says. When he browses the Library of Congress’s online archive, he’s looking not only for architecture that anchors the scene to the present day, but also for intrigue.

“I have to do a ‘spray and pray,’ where I’m going through an entire collection,” says Powell — clicking through thousands of photos to find just a few shots. Sometimes, he finds great photos that he can’t shoot because of security around government buildings.

“Half the photos I’ve taken of actual streets in D.C. are taken in the road, so I have to bring a spotter out there with me,” he says. “I get my fiancee to keep me safe from traffic.”

Powell, who recently left a job as a network engineer, is working on a Looking Into the Past book but hasn’t found a publisher. He says he considers himself to be equal parts historian and artist and is beginning a series of photos of Civil War battlefields and will travel to the precise sites where photographers stood for each of the historic photos.

“This is a documentation of me being here,” he says.