This is my first serious approach to model a face in MH using reference pictures (front and side). So if I made a mistake, please tell me.
I scaled and aligned front and side using Gimp so that side and relevant face parts match. My problem starts, when I set these images as backgrounds in MH. I have to use the mouse to scale and move the image and there's no numerical feedback about how much I scaled and moved. This renders my alignments in Gimp useless. I have to do it again in MH which will never be as accurate than my work in Gimp.
My idea: Implement background images like Blender does. There you can enter a value for x and y movement and scaling numerically. I think it's almost impossible to scale two images the same way just with a mouse.