On the internet, I stumbled about some questions about what HDR files are.
An HDR image is an HDR file encoded and saved by HDR software to retain the high dynamic range nature of the originally generated data.
Please take a look at my two example hdr files here:
Saving source HDR files
Within easyHDR, it’s possible to save concrete HDR files directly to disk. This way, you’re able to reopen the HDR files again. So this is a real source HDR file, saved by easyHDR as openEXR, an high dynamic range imaging image file format (fortunatelly released as an open standard along with a set of software tools).
Now let’s compare those hdr files, especially the file size is very interesting. The rendered HDR files are exactly the same size as the original three JPG photos.
But the saved openEXR HDR file is much bigger. This is because easyHDR has saved all the HDR rendering information within this file format. So I can reopen this exr whenever I want and so some HDR rendering modifications, for example reder it by one click from “dramatic dark” to “night”.
To complte this post, I’d like to provide the three source files (in JPG format, of course):