I did a little bit of experimenting. Target - to get the best resolution possible i.e. Native Resoution of the Google image (it should work with all the rasters).
Zoom to NR shows the scale 1:564
Map units per pixel / scale / tif file size (just for fun)
1.000 1:4724 132 MB
0.500 1:2362 449 MB
0.250 1:1181 1.65 GB
0.100 1:472 9.95 GB
Dependency is linear, thus:
1:564 gives —> 0.1194 maps units p.p.
File is quite large and covers area approximatelly 6.3 x 5.2 km in N.R. that gives the scale 1:564. (I could have selected smaller area for testing purposes…).
Tested on an area of my interest in Eastern Turkey.
What those mentioned “maps units per pixels” really are, remains a mystery for me.
Tile size parametr will be examined later. Output was always a single file.