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huge storage space for old versions in C:\Users\<user>\AppData\Roaming\ON1



  • Marius Müller

    Just checked some more details.
    Majority of the data is in the PerfectBrowseCache ~200GB.
    This may contain the previews... however... 200GB of previews???? Can't be or?

    and still 75GB of Old Version folders Resize, Effects, Photo RAW 20xy, Extras....

  • Rick Sammartino Community moderator

    The older folders you can delete. Don't mess with the cache, you need that. Here is what ON1 says about it...

  • Marius Müller

    Thanks for the reply Rick!
    Thanks for sharing the table - the size of the cache folders matches to the number of photos as well as the resolution and quality. :(

    I'm not worried about the disk space - already upgraded to 2TB SSD. 
    However - I've the feeling that i crossed any boundary - ON1 is meanwhile very slow and I was wondering whether this could be a reason. 

    Will remove it and re-install maybe this helps.

  • Brian Lawson Community moderator

    As long as your set up does not change, removing and reinstalling the software won't change anything either. For one thing, it leaves behind all of that user data you are concerned about. Optimizing your system is a better solution.

    I have a fast, external SSD which is reserved for photo processing software's Scratch space needs and I've moved the PerfectBrowseCache there as well for 2 reasons - to remove both that space requirement and the I/O overhead from my boot drive. Photo RAW now has a dedicated I/O channel for working with the PBC which helps with speed when browsing.

    I also have my photos on their own external drive. This has several practical reasons. I've moved that drive (or its contents, the actual drive has been replaced over the years) across at least 5 different systems. New system, just plug in the same old drive and I'm back in business. Once again, it separates the I/O channel for reading the files from that of the boot drive with all its OS caching and swapping and the user data updates Photo RAW needs to make while editing.


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