Stop UV map Stretching after resize

Im trying to resize the UV map area from 4096x4096 to 4096x2048 but the UV map stretches like the pictures below.

Normal 4096x4096

Stretched 4096x2048

I want it to look like this as 4096x2048

Without the need to manually resize the UV islands

What i want to do is get rid of the extra empty space below and above the UV island, I want to simply crop out the extra UV map space above and below the UV island, similar to how you would crop out extra uneeded space in a picture using Photoshop

How do I make the UV space 4096x2048 without stretching the UV islands?

In the N panel set the 2D Cursor to 2048,1024(center of image) In the header set the pivot point to 2D Cursor. A to select all. S Y 2 to scale the Y axis by a factor of 2.

Ok thanks I’ll give it a try! I’m just curios to why the pivot should be the 2D courser instead of the median of the total islands?

The median point won’t be precisely in the center of the image. I’m assuming a case where the image texture is cropped, 1024 pixels from both top and bottom. By scaling precisely on the center of the image the UVs will still fit the same texture.

EDIT: Also keep in mind that the median point is an average of the UVs so the door cutouts and differences between the front and back of the bus, will cause the median to be pulled off center. The best way to find the geographic center of a map like that is to use the bounding box.

Ok good to know thanks