Oyster, the hotel reviews brand, says that HDR, or high-dynamic-range imaging, is the secret to making panoramic images look their faithful best.
Oyster, acquired 18 months ago by TripAdvisor, has recently ramped up its use of panoramic shots of hotels. These images also appear on TripAdvisor reviews, too, by clicking "Expert Photos" on a hotel review page.
Why HDR?
A typical digital camera can't record details in highlights and shadows at the same time. If it exposes for the highlights, the shadows go too dark; and vice versa.
Applying HDR evens out the differences, says general manager Eytan Seidman.
Non-experts may associate HDR with high-contrast, almost three-dimensional and highly aesthetic images championed by travel photographer Trey Ratcliff, among others.
Oyster's use of HDR is different.
Here are two examples of the same image of a hotel: the first is untouched, the second one has had HDR applied to it.
In the non-HDR image, certain details are completely blown out – for example, the windows are basically all white.
The HDR image, below, is more faithful to how the human eye would observe the room. (Eyes automatically adjust for variations in brightness and shadow.)
The HDR image obtains a more consistent exposure throughout. For instance, note the detail in the window: It lets a viewer see that there's a building across the street.
Oyster uses HDR with a fisheye lens, which takes 360-degree images, while the camera rotates on a tripod.
Oyster typically takes four frames of varying exposures, such as, the first frame at +2 stops, and another at -2 stops -- with constant turns at 90 degrees.
Back at headquarters, HDR software blends the frames together with tone-mapping.
Booming business
Seidman says life has been good since TripAdvisor's acquisition of the startup he co-founded six years ago.
The New York City company has published reviews for more than 10,000 hotels across 76 countries and six continents -- a tripling from the 3,100 hotels it had at the time of its acquisition.
The site claims 1.7 million unique visitors a month, on average. It has 35 full-time staffers, with 100 freelancers.
The company plans to ramp up its search engine marketing and editorial content public relations efforts in Britain. Last May it added its first few London staffers. Says Seidman:

"Now we have properties in Tunisia and the Maldives and Morocco and other holiday spots that are relevant to a U.K. audience."
Globally, the vast majority of reviews and photography are done with the cooperation with hotels. Seidman says:

"We pay for our own travel. No cash is exchanging hands. But we ask permission before taking the HDR panos.
We do the selection. Hotels can’t pay to be on our platform. We get a lot of emails every day asking. But we set our priorities for which ones to include."
One factor for Oyster is consumer demand for a destination. Another factor is if a property that seems as if it is visually appealing.
More broadly, the company's goal is geographic saturation and, where possible, owning the top-ranking canonical URL for each hotel in search results.
TripAdvisor has a business relationship with about 80,000 hotels through its business listings product. But that division is walled off from Oyster, says Seidman.
Still versus video
Video is unappealing for Oyster right now, adds Seidman. Still imagery continues to trump video when it comes to reviews. Consumers prefer to consume imagery in a nonlinear format, argues Seidman.

"If I'm a traveler, I may care about the beach cabanas and the suites, but not a standard room or the hotel's restaurant. If I'm offered a carousel of still images, I can more quickly consume what's most important to me.
Video is too slow.
Still images are also higher resolution than video and load faster."
HDR panos images are available for 2,800 properties on Oyster now.
The goal is to have nearly all new properties photographed with HDR panos by the end of the year, on an ongoing basis. But it will take time to train staff and get equipment distributed.