Satellite images sharp enough to show details such as manhole covers, stop signs and lamp posts will soon be available in Canada and around the world, after the U.S. loosened limits put in place years ago due to national security concerns.

Starting early next year, the U.S. government will allow the commercial sale of black-and-white images with a resolution of up to 25 centimetres and colour images of up to a metre, confirmed Tahara Dawkins, director of the Commercial Remote Sensing Regulatory Affairs for the U.S. National Oceanic and Atmospheric Administration (NOAA), in an email to CBC News.

Starting earlier this month, satellite imagery companies have been allowed to sell black-and-white images with a resolution of up to 40 centimetres and colour images with a resolution of 1.6 metres.

Before now, satellite image providers weren't allowed to sell black-and-white images with a resolution higher than 50 centimetres or colour images with a resolution better than 2.0 metres even though at least one U.S. satellite image provider, Longmont, Colo.-based DigitalGlobe Inc., was technologically capable of collecting higher resolution images. At the allowable resolutions, it's possible to see cars and houses, but not always details such as manhole covers or mailboxes.

"Once you start looking at the difference between 30 to 50 [centimetres resolution], then you're getting into a very considerable difference and the types of things that you can see in the imagery are considerably different," said Sam Lieff, general manager for Lethbridge, Alta.-based BlackBridge Geomatics, which distributes images from DigitalGlobe alongside images from its own RapidEye satellites.

"What's really interesting about that is once we get into this really high resolution imagery, we become competitive with aerial photography."

That means companies like his will soon have access to a wider range of clients who are looking for images for applications ranging from city planning to forestry management, he said.

The previous ban on sharper images affected satellite image distributors around the world, including BlackBridge Geomatics.

"As commercial distributor, we've never been able to sell the imagery at its highest resolution until now," said Lieff. He acknowledged that could be frustrating for clients.

14-year-old rules

The previous rules were put in place by the U.S. Department of Commerce 14 years ago.

"The whole basis of it is really … security and military reasons," Lieff said. "The U.S. military doesn't want precision imagery getting into the hands of a terrorist organization."

However, DigitalGlobe petitioned the government to loosen the rules ahead of the launch of its Worldview-3 satellite, which will collect images with a resolution of up to 31 centimetres. The satellite launch is scheduled for August.

DigitalGlobe announced on June 11 that it had received notice of the new resolution rules, including one that would allow resolutions of up to 25 centimetres starting six months after its Worldview-3 satellites are operational. The company declined to be interviewed.

Dawkins said the national security community was fully involved in the decision to loosen the rules and the changes "do not curtail our authority to limit data collection and distribution of imagery in certain circumstances to address national security concerns, foreign policy interests, and international obligations."

However, she noted that given the advances in remote sensing and commercial imagery, NOAA also has a national security interest in "seeing that U.S. companies are competitive in the growing commercial imagery marketplace."

Lieff said since 2008, satellite image distributors have had to disclose all their users to the U.S. government so it can be checked against lists of terrorists. He added, "There just haven't been any bad issues that have happened."

Rules relaxed

He forsees that the relaxed rules will provide opportunities to sell satellite imagery for applications that would have once relied more heavily on aerial photography, such as municipal planning, oil and gas pipeline placement, mapping the kinds of trees in a forest, or mapping elevation changes for mining.

Satellite mapping is faster and easier than aerial photography, Lieff said.

However, he noted that aerial photography can take images with resolutions much higher than 25 centimetres, and will remain the only option for clients who need that kind of detail.

While the new rules apply to all U.S. commercial satellite operators, NOAA says DigitalGlobe is the only U.S. satellite provider capable of providing images with a resolution close to 25 centimetres by next year.

But Lieff says the rule change opens new doors for other companies "including ourselves."

"There's new satellites coming up that will definitely breach the 50-centimetre resolution," he said. "We're just looking a few years out, really."