Over the past year HDRI Haven has grown to become known as a resource for high quality HDRIs. Greg Zaal who runs the site and shoots the HDRIs available on the site used to sell the high quality, 16k HDRIs. Now, he's releasing them all for free.
On June 2nd, 2017, Greg started releasing a free 16k HDRI every Friday. People loved it. They loved them so much, they started to buy the HDRIs. This convinced him, he could release all of them for free and still earn enough to create more HDRIs, support the site and maintain the required bandwidth. On October 1st, he released all the HDRIs under a CC0 license, making them available to everyone for any use.
At the same time, he launched a Patreon page to allow the HDRI Haven community to help reach the goal to support the continued creation of the HDRIs and maintain the website. If you've ever thought about providing resources online, Greg's Patreon page is a great example of how you can do it.
Greg has a wide variety of HDRIs available and the price can't be beat. While Studio HDRIs are not available, he has an incredible set of Indoor, Outdoor, Nature and Urban environments he has shot. They're all unclipped too, meaning it contains the full dynamic range of the scene to provide the most accuracy and realism.