I need Earth radius in pixels for use in Mercator projection. Well let's say that our map's height is 1478 pixels and distance between 0 pixel and 1478 pixel is 2.52 degree. Radius is distance from the equator to pole so the formula for count Earth radius in pixels is R=90/2.52*1478 which is 52785.71429. Well then pixel number for 48.54 degree is 51287.99461 and for 51.06 is pixel number 54885.98194 counted by Mercator so the diference is 3597.987328 which is not correct because it should be those 1478 pixels. I think that Mercator formulas are good because when i make inverses of pixel i get the degrees as in input so mistake can be only in Earth radius. Am I missed something, are my calculations right? Thanks in advance.