Skip to main content

.onphoto files



  • Rick Sammartino Community moderator

    .Onphoto is not a sidecar. When you add layers in Photo Raw and later save that work or a new file needs to be created for HDR or stacking, it's saved in the .onphoto file. 

    .on1 and .xmp are the sidecars.

    • .on1 holds your work if you didn't need an .onphoto. When you export, the work in that file gets merged with your original photo to create the final edited photo.
    • .xmp holds metadata for compatibility with other programs.

    Many times you will get a new file after sending a photo to another program because the changes it makes can't be saved to the original RAW so it has to save those changes somewhere else. That's what results in a new file.



  • David Tillett
    Great answers

    I have never had random jumps to Resize or Print, what exactly were you doing at the time?

    In basic editing of a file in PhotoRAW the original file remains untouched and details of all the changes are recorded in PhotoRAW's database, in the Files section of the PhotoRAW preferences there is an option to have these changes recorded in a .on1 sidecar file. This acts as a backup to database and also means if original file and its .on1 sidecar file are sent to someone else with PhotoRAW they can carry on with the editing.

    For more complex edits that involve layers, including calling another program as plug in a new .onphoto file is created alongside the original file, and any .on1 file associated with this. This is On1s equivalent of Photoshop's PSD files that contain layers. This file gets created when you click done on Edit.

    Since other programs can't read On1's edit information when sending to an external program either via Send To or as a Plugin PhotoRAW has to render the image with all the edits applied. If a plugin is being called then this rendered image is passed behind the scenes and does not create a new file, or not until .onphoto file is created as above.

    For external editors the rendered image has to be passed as a file that the external editor can read, so a new copy file has to be created. In the Files section of Preferences one can specify which type of file is created for all such transfers or set it to prompt for the type when transfers are requested.

    Unlike Lightroom PhotoRAW also gives option to transfer the original file without any PhotoRAW edits.

    What happens at the end of the processing in the external editor is really down to the external editor, the type of file passed and how editing is terminated. For example Photoshop is able to save a new version of a PSD file if that is what PhotoRAW has sent to it automatically if edit window is closed, so only the one PSD file exists. On the other hand if a TIFF has been passed then various save dialogues come up and it is possible to then save as TIFF overwriting the original file.

    To sum up

    - there is the original file that you have brought into PhotoRAW

    - depending on Preferences you may get a .on1 sidecar file for photos you have edited or changed metadata on, also if you have changed metadata you may get a .xmp side car file. First holds information that only On1 products understand and latter standard meta data information for interchange between programs

    - if you add layers during editing in PhotoRAW a .onphoto file is created when editing of that image is finished. From then on this is the file that you should chose if you want to continue editing in PhotoRAW or send to external editor. This lives besides the original RAW file.

    - if you send to an external editor such as Photoshop you have the option to either send the original unedited file or one that includes any PhotoRAW edits. In the second case you can choose which format to send to the external editor

    - if the original file is sent then the external editor will need to create its own new file that contains the work that was carried out in it. Type will depend on decisions made in external editor, nothing to do with PhotoRAW

    - if a rendered file is sent then the external editor will also need to create a new file or version of the file to contain its work. There may be options to overwrite the file that PhotoRAW sent but again that is down to the external editor and the type of file involved

    If I am using Photoshop then I normally send a PSD file over and overwrite that at the end of the editing, so I normally only see the original file and the PSD file in PhotoRAW, and sometimes .onphoto files, and do my file management in PhotoRAW so side car files get handled behind the scenes.


  • Roy Gaylard

    Thanks so much for the detailed responses - this will allow me to work more efficiently - for one, I'll make a subfolder for all the copies so that when I'm finished with a batch, I won't get the keeper files mixed up with the discards.  Secondly, I'll do my tidying up in On1, not explorer, so I won't get to see the .on1 and .xmp files.

    @David Till - this random switching of modes is another of those very annoying things about On1 which make me pull my hair out!  This usually happens when I pull down on the slider next to the printer etc, icons.  At first I thought I was being sloppy, but this is not the case.  I don't even click - simply moving the mouse indicator in the near vicinity of the icons is enough to trigger the switch.  Yesterday this happened when I adjusted the saturation slider - which is a long way from the print and resize icons.

    Such a pity about these annoying actions - the best software for editing I have come across, to be marred by instability.  Unfortunately, about the only solution that can be offered by Technical is to delete preferences - pretty pointless advice.

    Thanks once again for your assistance:)

  • Rick Sammartino Community moderator

    Actually, deleting the settings file fixes a lot of things. Unfortunately, that doesn't say much for that file causing so many problems.

    As for your random switching, honestly, you're the only one that's ever mentioned it to my knowledge. I'm more likely to suspect your PC sending erroneous keycodes that are activating certain modules.

    So here is a suggestion, see if any of those modules have a hotkey assigned to them. If so, change the keycode temporarily. If the random changes stop, then that's what's happening.

  • David Tillett
    Great answers

    Roy, I have just tried to "accidentally" switch modes. Everything I tried actually need a new click, just running off sliders with mouse button down didn't enter the new mode.

    I am on a Mac and tried with mouse, trackpad and Wacom tablet.

    What I did find is that the clickable area for the mode change is more than just the icon. Clicking anywhere to right of scroll bar on level of icon is enough. But again it needed a new click to actually trigger the mode change.

    Both Print and Resize have hotkeys, cmd-P for Print and Y for Resize. Probably difficult to accidentally trigger Print but a sensitive keyboard might trigger a Y if fingers resting on keys while using mouse.

    I have been using On1 for several years, back to PhotoRAW 2019, and have never had an unexpected change of mode. And as Rick says you are the first person to ever mention the problem on the forums.

    What system are you running? On1 uses a third-party package to handle its user interface, and other packages also use the same package, Topaz does/did for one. I have avoided Windows since I retired but back in the bad old days if applications used different versions of support software then they could interact in a nasty way. I have no idea if this problem still exists but some other application interfering with On1 is the best thing I can think of as being behind your problems if it is a software cause.

    Have you tried with another mouse? Could this be generating unexpected clicks? As I found clicking when near the icons does trigger the change of mode but with my mouse it requires a real click. 

  • David Kick

    Roy, I am on Windows and, like the others here have said, I have never had a random switch of modes. I agree with David Tillett, perhaps try another mouse.

  • Barry Combes

    Perhaps Roy has done what I have done occasionally by inadvertently clicking on the Resize etc. icons when trying to click on the scroll bar, on my 21” screen the scroll bars are only  2mm wide.

  • Roy Gaylard

    Thanks for all the useful comments:)

    On planning my reply, I tried my best to re-create the fault - to no avail.  Dragged the mouse pointer all over the icons and they never changed modes - even had to click a few times before they would respond.  Seeing as this appears to be not a known issue, when it happens again I'll put in a fault report with log file and see whether Tech can come up with something better than "update the drivers and/or delete the preference file" :)

    I'm on Windows 11, using a wireless mouse, if that is at all relevant.  If this happens again, I'll try using a usb mouse or the trackpad - which I hate with a passion!


Please sign in to leave a comment.