Strictly speaking, HDR [High Dynamic Range] simply means that you have more data available in an image [or images if you're talking video]. HDR will Not make a poor or mediocre image into an award winning bit of photography [or cinema], so in a bid to sell more TVs etc., manufacturers adjusted the display modes of their TVs & monitors to unrealistically add more colors -- the goal was to make it easy to see the difference HDR made. That sort of thinking caught on with the marketing folks, with a sizable amount of the public, who grew to expect [maybe just short of] garish colors with HDR, and with Franzis. PURE HDR is a 6 month younger version of HDR projects 5, with less of the focus on adding unnatural colors & lighting that you'll find in the HDR projects app. Like the other Franzis HDR apps, PURE HDR is harder than it has to be with all sorts of controls & options that might assist you in altering colors & lighting. If that's your thing [and I don't mean to judge], you can already do all that in most image editors without the extra work that's HDR. HDR just lets you work with more data than usual while using the same tools, skills, & techniques as always.
Franzis skipped their usual wrapper this time, giving us the PURE HDR setup file and a URL to request a key. Installation adds old C/C++ runtimes from Microsoft, 2 folders in Users\ [UserName]\, and triggers a rewrite of Windows Component hive, with something like 60k new entries.