I import my original files in Lightroom CC. I sync my collection with Lightroom Mobile. I use the new Open in Photoshop for IPad. I edit the image in IPad and when I click on the option to continue working with the image in Lightroom for Mobile the file is now much smaller than the original. It's the size of the smart preview that I'm warned about when I open the file in Photoshop for IPad. So the result is the work I have done on a file that was originaly 9537x11419 is now 2138 x 2560 in both Lightroom Mobile and in my Lightroom CC. Of course I have the original untouched file but why work in Photoshop for the IPad if this is the results? In other words is there some way to maintain the original size of my files through the entire workflow?
When you say, "I import my original files in Lightroom CC," it sounds like you really mean "Lightroom Classic (LrC)." (I could be wrong in my interpretation, if so, skip to the second paragraph). If your photos begin their life in Lightroom Classic, any photos imported there will never make their way to the Cloud and to LR Mobile as anything more than Smart Previews. That's the way Lightroom Classic works with sync. If you have an original on your mobile device, you'll temporarily have access to the full res version - until the next time you sync to your desktop, at which time any full res versions will download to the desktop and be replaced in the LR Mobile universe with Smart Previews.
The only way to get what you want is to switch completely to Lightroom CC ("Lr," the cloud storage version), In which full resolution images are stored in the Cloud. Even then, your mobile device may have only the Smart Preview locally, to save space. In that case, you'll have to go to the three dots menu for the Album, and choose the option "Store Locally." This will pull the full res version from the Cloud to your mobile device. Note that as far as I know, this can only be managed at the album level, and not the individual image level.
Once the full res image is on your device, editing in Photoshop on the device will utilize the full res version of the image.
Thank you for this great explanation. It makes sense and I understand that Lightroom Mobile really functions like it does because we're working with lower resolution smart preview files. Some of mine are drum scans so they're way up there.
What I thought was yes, Lightroom Mobile and Photoshop for IPad would work with smart previews then when they were synced back to my desktop with Lightroom Classic the changes would be saved and miraculously applied to the full resolution images that were originally loaded into and reside on my Lightroom Classic.