HDRMerge is an awesome FOSS program from Javier Celaya for generating a high dynamic range raw image in the DNG format from a bracketed raw set. https://github.com/jcelaya/hdrmerge Please add support for correctly displaying the thumbnails from these raw images. They follow standards and should therefore be supported. You can download a sample image from: http://rawtherapee.com/shared/test_images/hdrmerge_045.dng Currently Gwenview shows only the thumbnail of the first HDR DNG image in a folder. If there is more than one, the other images get the thumbnail of the first image. Furthermore, clicking on the DNG shows "Loading 'hdrmerge_045.dng' failed. Loading meta information failed". http://i.imgur.com/aTbXMEa.png
Still not supported in 4.14.0, and 4.14.0 is not available in the "version" combobox.
In Gwenview 16.x and up, thumbnails appear to be generated correctly when there are multiple .dng files in a directory.
Gwenview 17.08.2 shows HDR DNG thumbnails correctly. When clicking on a thumb, the preview is small, almost the same size as a thumb. I know that the files have large previews embedded, and it would be nice if Gwenview showed those large previews, though that's a separate issue.