"It's because a lot of the parts of those cars are, in fact, sexy," he says.
You could think of car parts as jewelry -- sort of like designer accessories for cars.
Example: the taillights on the 1959 Cadillac Series 62.
These beauties, seen in the first photo above, have transcended manufacturing and entered the world of pure art. They're like rare ruby earrings. On wheels.
"The rear taillights on the 1959 Cadillac are just overwhelmingly beautiful and iconic," Edson said.
Some folks refer to that car as the "King Fin Caddy" because it represents the peak of Detroit's love affair with tail fins, started by legendary General Motors designer Harley Earl
The look and feel of those signature double taillights, wrapped in chrome, just scream the culture of the 1950s. If you listen hard enough while you're looking at those taillights, you can almost hear the doo-wop music coming out of the AM radio in the front seat.
When you look at the photographs in Edson's series "Car Details," you can tell he is no gearhead. He admits he's a guy who loves the outside of cars way more than what's under the hood.
"A car is the sum of its parts," he said on the phone from a car show in Plymouth, Michigan.
"I'm not really involved with photographing whole cars," he said. "My interest is really in looking at the details and the abstractions of these parts and finding the art in the smaller views of cars."
Edson finds beauty in the things we take for granted in our cars -- the dashboards, odometers, front grills, headlights, hubcaps and light fixtures.
"When you look at cars," he said, "functionality has to merge with an aesthetic. ... There's a beautiful integration of form and design and functionality."
He's always been fascinated with automobile design -- like many Americans of his generation who grew up in the 1950s and 1960s, "when manufacturers were always trying to appeal to the people's vision of the future."
His first car: A Volkswagen bug he bought in the early '70s for $75. Now he drives a Jaguar.
Cars from what he calls the "Golden Age of classic vehicles" -- the 1930s through the early '60s -- get most of Edson's attention.
The hood ornament: 'The spirit of the vehicle'
Edson clearly appreciates the glimmer of a chrome hood ornament -- like the "Star Chief" from a 1941 Pontiac, No. 12 in the gallery above.
Another decoration featured in his series: a "chrome rocket" side hood piece from a classic '57 Chevy Bel Air.
So simple, elegant and cool -- as in '50s cool, back when the word "cool" was new.
"The hood ornament is sort of like the spirit of the vehicle," Edson said. "That's the first element of a car that I've become attracted to. The detail that has gone into these hood ornaments is stunning to say the least."
Does anyone make sexy cars anymore?
Sadly, most of today's car designs are "homogenous," Edson said. They offer little of interest.
But there are exceptions, he says.
The body styling of the new Aston Martins and the Jaguars designed by Ian Callum are worth looking at, to name a few.
"The flow of metal and light and how it bends around a vehicle are really astonishingly beautiful," Edson said. "They've made cars more sleek. If we look at the Maseratis and the Ferraris and the Porsches, you can see that these cars breathe life, but it's a different type of life than the cars that we see from the '30s, '40s and '50s."
Edson has been exploring photography art since the 1970s, creating artful portraits, street photography and architectural portfolios.
The car project has been calling him for several years, taking him to auto shows around the country where he'll search for unique or unusual opportunities for extreme, abstract close-ups.
"My process is getting to shows early in the morning and walking the shows for three to four hours, many times coming back to a car and looking at a car in different light as the light has changed," Edson said.
Does Edson think any of the design stylings of the "Golden Age" will ever return to new car showrooms? He's not sure.
"I guess we'll have to wait and see which designers and car manufacturers are willing to revert back to the future."