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Inconsistent creation of .onphoto files from DNG



  • Brian Lawson Community moderator

    Let's take the easy one first. No, there is no way for you to create a .onphoto format file on your own. They are ON1's proprietary format for layered RAW files and are supposed to be created automatically when you add a new Layer to a RAW image and after you end the editing session for that image.

    Why do you create DNGs to be edited and how are you creating them? Since Photo RAW is a non-destructive editor you are adding an unnecessary step and creating an additional file to eat your disk space and to keep track of for no reason. IMO you'd be better off starting with the original RAW file unless you have some specific need for the DNG. You'll also find that editing the RAW file vs editing its DNG version will give you better results. At least that is what I've found. I actually went through all my old DNG's and extracted the original RAW files where I had embedded them when I created them with Adobe DNG Converter back when I was using Adobe's programs for this reason.

    I just opened a DNG (created with Adobe DNG Converter) and used the Add Layer button to add a second copy of the file. I applied the Overlay Blending Mode and clicked Done. The program displayed the Saving dialog but no .onphoto file was created. Reopening the .dng opened the original, unlayered version and I could not find any .onphoto file for it. Repeating the process only this time using the Duplicate Layer button to add the duplicate Layer and pressing G to return to the Browser did create the .onphoto file.

    It appears there might be a bug when using the Done button to end the editing session with a new Layered image that prevents the .onphoto file from being saved even though the Save dialog is shown. You might want to report this to tech support. I'll have to do some more testing before I submit one of my own. I would include the link to this forum topic and a link to download one of the corrupt layered DNG files for their engineers to examine. You most likely won't be able to include it as an attachment so you'll need to upload it to a file sharing service like Dropbox or WeTransfer and include the download link in your support request. I would zip together the corrupt DNG, the files used for each Layer, and the .on1 sidecar file and upload that for them.

    How to submit a problem to ON1 Tech Support - A Step-by-step Guide

  • Brian Lawson Community moderator

    Update: I repeated my first test using the + and Done buttons and this time the .onphoto file was created. I've submitted a bug report but you should too.

  • Richard Toft

    Thanks very much for your rapid input Brian. Regarding the use of DNG's, there are two reasons: 1) company policy re archival needs - DNG is a much more widely read format than the great multitude of camera raw formats, so in 100 years time it is more likely something will still be able to read a DNG file rather than a format a particular camera manufacturer used for a few years in the early 2000's. 2) There is another piece of software I use that forces multiple images directly from a camera system and through Adobe DNG Converter before they even get to ON1. Converting to lossless DNG's without the original embedded raw files are actually no bigger than the camera raw format, so it isn't using any more disc space. So far the only issues I have noticed when editing DNG files is when I have converted raw files using On1 itself (there is something odd about the highlights and exposure, as well as being HUGE). I haven't seen these issues with the other DNG's I use.

    Anyway, all that is another subject. I'm pleased you were able duplicate the issue re occasional failure to generate .onphoto files when adding layers. I have done some other tests and noticed the issue turns up if the DNG has previously had other edits applied (e.g. effects like dynamic contrast). If I then reopen that file to edit again and add a simple colour fill layer, it refuses to create the .onphoto file. 

    I'll submit the problem as suggested.

  • Brian Lawson Community moderator

    I did say unless there’s a need. That sounds like a pretty good one. :)

    You should tell them about it being a problem only for DNGs which have been edited. 


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