​Instagram rolls out 30-second ads, but will fans approve?

Change is hard, especially when it comes to a favorite social-media network.

Instagram is expanding its advertising efforts, reaching out to businesses of all sizes and in countries ranging from India to South Korea, while also adding video ads that can run as long as 30 seconds. That length isn't likely picked at random, given that 30 seconds is the length of a traditional television ad.

While TV viewers may be used to sitting through commercials (although plenty try to ad skip or visit the kitchen when ads come on), it's unclear whether Instagram followers will tolerate video ads to the same degree. Instagram's roots are in photography, and many members visit the app or the site to check out striking images from publications such as National Geographic as well as to catch up with friends' goings-on. On top of that, consumers tend to prefer shorter videos ads online, which makes a 30-second ad more of a risk, according to Adweek.

While some Instagram users were already grumbling on social media, investors didn't seem to be bothered, sending parent company Facebook's (FB) stock up 1.8 percent in afternoon trading on Wednesday. Instagram didn't return a request for comment.

The reason for the longer ads is to provide brands with "richer storytelling," the company said in a blog post.

The expansion of Instagram's advertising business has been a slow evolution, with Facebook COO Sheryl Sandberg calling the company "very cautious" in a July conference call. There's good reason for that approach: its audience is largely under 34 years old, the prime demographic for advertisers. But that audience has also grown up with a largely ad-free Instagram, and tossing in commercials could do more to alienate the audience than endear it to the service.

Still, Instagram is citing a few examples as illustrations of how ad campaigns are winning over customers. Gilt Groupe, an online shopping site, ran a campaign that Instagram said boosted installations of its site by 85 percent, for one.

"People come to Instagram for visual inspiration, and advertising on Instagram has the power to touch, inspire and move people," the company said. "Instagram ads have proven to drive strong branding results 97 percent of measured campaigns on Instagram have generated significant lifts in ad recall."

It could also bring in heaps of revenue, with one market researcher estimating that mobile ad revenue from Instagram will more than double to $1.48 billion next year.