Netflix Super HD now available to all its subscribers—maybe

If you've been jealous of those Netflix subscribers who were able to get the company's highest-quality Super HD video streams, it's time to find someone else to envy. Netflix is rolling out access to Super HD videos to all its subscribers, provided they and their Internet service providers (ISPs) have sufficient broadband speeds to handle it.

Netflix is also making its 3D content available to all subscribers. For those with (or thinking about getting) an Ultra HD TV, the company recently said it expects to start delivering 4K Ultra HD content sometime next year. By that time, many TV sets will come with new HDMI 2.0 inputs, which can handle 60Hz Ultra HD content.

In addition to higher broadband speeds, you'll also need a 1080p TV to take advantage of the higher-quality Super HD videos. But if you have the right set and high enough network speeds, the payoff is considerable—great-looking streaming videos.

Consumer Reports recently performed a head-to-head shootout of movies delivered in Netflix's Super HD format and the same movies sent in Vudu's HDX format, which had previously provided the best streaming quality we'd seen to date. Though there were some minor differences, overall video quality was nearly identical, just below what we get from Blu-ray discs.

Curious about other streaming services? Check our streaming video and movie rental buying guide.

Until the rollout earler this week, Netflix Super HD—which uses less compression on high-def images to improve picture quality—was available only to subscribers who got their broadband from an ISP that had adopted Netflix's Open Connect content delivery network. That system places caching servers locally near the ISPs, creating the potential for better-looking videos (since they're stored closer to where you live) and relieving network congestion.

But there's no guarantee you'll get Super HD videos even if you can receive them. For one, not all movies are available in that format. (The Super HD logo is listed on the movie description page if applicable.) And like most streaming companies, Netflix employs a technique called "adaptive streaming," which dynamically adjusts the quality of the video you receive based on available bandwidth. (The concept is that it's better to get a continuous lower-quality video stream than a higher-quality one that breaks up or constantly stops to buffer.)

For Super HD videos, Netflix recommends consistent bandwidth of at least 7 megabits per second (Mbps). The highest-quality 3D will require about 12Mbps speeds, and Ultra HD will require even more.  Netflix says the best experience will be through ISPs that adopt Open Connect.

On its website, Netflix offers subscribers an ISP Speed Index that tells you how well (or poorly) your ISP is doing in terms of average broadband speeds, although some have criticized it as an overly simple tool that does not accurately measure Internet quality. Our advice is that since even the fastest ISP provider—Google Fiber—has a listed average speed (3.58 Mbps) below the minimum required for regular HD or Super SD streams, you use it only as a relative measure of how well your ISP does compared to others.

—James K. Willcox