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PhotoSettingsCache constantly expanding plau what is in there



  • Rick Sammartino Community moderator

    The .on1 file has never been the only file required, it has always been a backup to the On1 database that contains your edits.

    You can even turn off the sidecars and On1 will work just fine without it, but you won't have a backup and you won't be able to move files around because when you move a photo with it's .on1 sidecar, On1 doesn't need to track it, it will use that file wherever it finds it,  to update the Database

    This article has the best info on how it works...

  • Martin Evans

    Thank you Rick but I don't think that article answers my questions.

    1. it does not mention the PhotoSettingsCache
    2. it does not address the issue of TIF masks in the PhotoSettingsCache (are these required to re-edit an image with a mask)
    3. is it a cache (temporary and deletable)
    4. why does it only grow and never shrink, can it be shrunk
    5. it doesn't seem possible to move it off your system drive

    I'll do further experimentation of my own with masks and moving images.

  • Martin Evans

    Ok. Simple experiment. Edit a photo in PR 2019. Select a filter (e.g. black and white), invert the mask and create an AI mask, select done and go back to browse. A directory appears in the PhotoSettingsCache\Files directory. In this directory is a 161Mb TIF which looks like the mask. The on1 sidecar file is 436Kb file.

    Switch on1 to a different folder and copy (with windows explorer) the photo raw file and the on1 sidecar file to another directory. Browse the new directory in on1 and open the copied raw file. Switch to effects and you can still you effect and the mask. So this seems to confirm the on1 sidecar file contains the mask because we moved the raw file somewhere else.

    Now delete the original photo raw file and on1 sidecar file (in windows explorer). The large TIF mask remains in PhotoSettingsCache. You can browse in PR the folders where the photo was deleted and even exit and startup again and go to the photo and the large TIF remains. There is nothing in the PR settings to clear this dir out. So it would seem this directory and only grow and there is nothing I can find to clean it up. It also seems the large TIF isn't required to re-edit the photo so what is its purpose.


  • Martin Evans

    Plus, you can delete the large TIF in PhotoSettingsCache and it does not effect re-editing the photo.

    If you rename a raw file and on1 sidecar file (outside of PR) you lose your edits as the original filename is in the sidecar file. If you rename in PR, all is ok.

    So it would seem from my small experimentation that you might be able to delete directories in PhotoSettingsCache. I wish the manual explained what this directory was used for and how to empty it so I could be sure as every mask I create seems to create a huge tif file that never disappears.

  • Brian Lawson Community moderator

    These are questions best directed to support Martin. You're talking with other users here and we don't know the answers to those questions either.

    One thing I might point out is that cache doesn't necessarily mean temporary, ready to be deleted when no longer needed. It can also mean a place where things get stored for later use. (I used to live in Cache Valley, named for the location fur trappers used to store their furs until they had enough to make a trip back into civilization to trade them.)

  • Martin Evans

    Thank you Brian. I am aware this is a user forum but there seem to be quite a number of knowledgable people on it so I thought it was a good first port of call.

    Whether it really is a cache or not is really neither here nor there if it just keeps growing and we have no control over it or information on what its purpose is (especially when it is on a system disk and cannot be moved). After I've done more investigation I may ask On1 support.

  • Eelco Westerhuis

    Hi All - I regularly delete the photorsettingscache (AppData\Roaming\ON1\ON1 Photo RAW 2020\PhotoSettingsCache) and providing the side car files are there it appears to make no difference and actually seems to make the programme more responsive for a bit - it appears to store bits of masking as you go along and various versions so realy not required. I also tend to delete the Fastbrowse Cache and the Fastbrowsedb as sometimes once again clearing this away gives the programme a new lease of life - I should mention being careful to not delete stuff that would take a long time to redo, catalogs etc however the fast browse is fast enough without saving a large database of thumbnails when the original files may already be backed up elsewhere and not likely to be seen again for quite some time.

  • Martin Evans

    To add a bit to my postings above. It also appears if you use the clone/stamp tool, TIF images are created in the PhotoSettingsCache.

    Also, if you edit a jpeg file and use the clone stamp tool tifs are created in PhotoSettingsCache. If you then close PR and delete these files then reopen PR, and edit the kpeg again, the TIFs are recreated.


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