Map WxH and Resolution ?

So i have a hand made landscape, and, its massive. To save on RAM and GPU (and time spent with foliage) i wanted to split the landscape via a script method in Photoshop.
When i export the heightmap via the landscape tools, i get a “8161x8161” map with a resolution of 72.
When i split the heightmap.png (single file) by 4, a few of the files are not the same size (size on disk) as the others so the import complains about that.
I can fiddle with the resolution (Image properties in Photoshop), and, say i make it 505 (or whatever official res i pick) and split by 4, it sometimes works.

In photoshop, setting the resolution to, say, 4033, it makes my PNG massive in size, something like 50,000x50,000. Obviously unacceptable size lol

Is there a WxH and Resolution i should be shooting for? Is there a way to export a heightmap so thats its not some weird res (in this case, 72)? I do not have WorldMachine and do not plan on getting it for a one time use function. Even to have someone import the map into WM and split it for me would be awesome lol

Script for photoshop im using:



var absoluteSavePath = "C:\\Users\\matth\\Desktop\\Splitmaps\\splitters\\"

doc = app.activeDocument; 

var tiles = prompt("How many tiles do you want?", 4, "Tile Amount");
var tileSize = ((doc.height-1)/tiles)+1;
var tileOffset = tileSize-1;
for(var x=0; x<tiles; x++)
{
for(var y=0; y<tiles; y++)
{
app.documents[0].duplicate();
var bounds = [x*tileOffset, y*tileOffset, x*tileOffset + tileSize, y*tileOffset+tileSize];
active = app.activeDocument;
active.crop(bounds);
saveOptions = new RawSaveOptions();
active.saveAs(new File(absoluteSavePath + "tile_x" + x + "_y" + y + ".raw"), saveOptions, true);
active.close(SaveOptions.DONOTSAVECHANGES);
}