Problem with raster converter

[AntonM]

I'm having a problem with the raster converter -- it seems to get the size wrong in one direction.

I did a screendump from Ordnance Survey's MemoryMap (a highly authoritative UK cartographer) and carefully entered into the converter the co-ordinates MemoryMap gave for the four edges of the map.

By inspection, the map looks like it has a W:H aspect ratio of about 8:5 (i.e., ±1.6), and looking at the co-ordinates provided by MemoryMap, that seems about right.

The converter agrees that the image has an aspect ratio of 1.578... but says the co-ordinates suggest a ration of 2.66...

The co-ords are -2.163 & -2.087 and 50.082 & 53.11. Just looking at the fractional parts of those numbers also suggests a ratio of ±1.6.

The converted map is, in fact, squashed in the Y direction, and thus unusable.

What am I doing wrong?

I attach a screendump of the converter window.