Questions about Atlas File generating

I just want to check that the results I'm getting with filesizes are what you would expect.

RAW file, 2048x2048 and a JPG file of 8192x8192.

I then use the following code:

setLogMode(6);
atlasOldGenerateChunkFileFromRaw16("legend/data/terrains/Nuin.raw", 2048, 4, 0.0126, "legend/data/terrains/Nuin.chu", 1.5, 5);

importOldAtlasCHU("legend/data/terrains/Nuin.chu", "legend/data/terrains/Nuin_geometry.atlas");

atlasGenerateTextureTOCFromLargeJPEG("legend/data/terrains/Nuin.jpg", 5, "legend/data/terrains/Nuin_texture.atlas");

atlasGenerateUniqueTerrain("legend/data/terrains/Nuin.atlas", "legend/data/terrains/Nuin_geometry.atlas", "legend/data/terrains/Nuin_texture.atlas");

echo("done");


This produces for me a Nuin.atlas file of 130 meg! 100 meg of which is texture.

Is this correct? There will be 13 "tiles" of 2048x2048, which would mean a total of 1.5-2gig for just landscapes!
The final texture doesn't appear too high res in the engine.

Are there some recommended settings?