pi@tcam:~ $ id -u
1000
pi@tcam:~ $ ls -la test
total 8
drwxr-xr-x 2 pi pi 4096 May 20 09:58 .
drwxr-xr-x 5 pi pi 4096 May 20 09:58 ..
pi@tcam:~ $ sudo mount -o rw,uid=1000,gid=1000,umask=0000 /dev/loop0 /home/pi/test
pi@tcam:~ $ ls -la test
total 132
drwxr-xr-x 5 root root 32768 May 20 09:29 .
drwxr-xr-x 5 pi   pi    4096 May 20 09:58 ..
drwxr-xr-x 2 root root 32768 May 19 02:22 $RECYCLE.BIN
drwxr-xr-x 2 root root 32768 May 19 02:21 System Volume Information
pi@tcam:~ $ touch test/test
touch: cannot touch 'test/test': Permission denied