Trying to import photos to my 2018 12.9 iPP using an SD card and a third party Cablematters micro SD and SD card USB C reader. Card itself is formatted FAT/Master Boot Record and all photos (which are RAW by the way - but this shouldn't affect anything) are in folder DCIM and follow naming scheme of 8 characters followed by file type. Import window comes up but with message 'no photos to import'. The ONLY reason I can think this is happening is that I'm not using Apple's own USB C adapter; is this the case? The reason I think this probably isn't the case is because surely the import window wouldn't come up at all if the device itself wasn't recognised by the iPad. I have tried using a JPEG file (just in case someone suggests it as a test) and get the same message. Help appreciated! Thanks.