Leaf Aptus *.mos files not opening

[narinderb94343671]

Today I was unable to import or open files from my external card which were in the *.mos format.  This is the format used by the Leaf Aptus digital backs, in this case a Leaf Aptus 65.  The issue occurs in Photoshoop and Lightroom.  I have tried two different external cards, and two different cameras (though the latter should make no difference).  I get a message to update Camera Raw, but I am running the latest version.  I am able to open other files from my other back: a Phase One digital back.  Interestingly I am able to open the *.mos files in all the other raw processors I have:  Affinity Photo and ON1 Raw 2020.  So I have to think this is an Adobe CR issue.  I spent an hour with support and having the tech do remote trouble shooting and his answer was that the file extensions are corrupt.  What does that mean? Why are they corrupt only for the adobe apps?  Why are they "corrupt" on both external cards??  It makes no sense - and I have opened these files before (albeit a couple of years ago).  I am running Windows 10 Pro - but the issue is the same on my Mac.  Any advice will be helpful.  By the way Aptus 65 is listed as being supported by CR.

[Jeff Arola · Accepted solution]

This is a Note from the following page about camera raw not supporting.mos files if they are compressed:

https://helpx.adobe.com/camera-raw/kb/camera-raw-plug-supported-cameras.html

Note:

Camera Raw does not support compressed MOS & IIQ files from Leaf cameras. If you cannot open your MOS or IIQ files in Camera Raw, try using a camera proprietary converter to remove the file compression. Proprietary converters include Leaf Raw Converter and Phase One Capture One.

[narinderb94343671]

Thanks, Jeff.  I will look into the settings on the digital back.  I am in the process of selling the back, and I reset it to factory settings.  It might well be that when I did this, the file capture reverted to a compressed format.  You may well have hit on the issue and solution.  I will post back with my findings.  Cheers!

[narinderb94343671]

Jeff, you are indeed correct.  I changed the setting on the back from lossless compression to none, and the images came thru just fine.  The fine print is always important to read :).  Thank you again for your help.  I will feedback into my support case as well, which remains open.  Cheers!

[AgNOthree]

and it is completely ridiculous that it doesn't read them as lots of other software does. Like Affinity Photo of all things. 

[jamesseaford]

Is there free software one can use to convert the mos file? I've been given these files and don't want to sign up for another program to be able to open them on PS. 

[Jeff Arola]

Have a look at Raw Therapee:

https://rawtherapee.com/