Hi,

So my design on the sigg bottle looks oblong, is there a certain ratio to make a circle graphic look like a circle once you print on a cylinder.

thanks

If the image you upload is a circle (same width and height), it will be a circle when it prints. What you're seeing on the bottle is the optical illusion that happens when you put a circle on a cylindrical object.

Right. So, any adjustment you make to give it the appearance of being circular in the thumbnail will just look wonky in the customer's hand as a slight turn of the bottle will show the distortion.

You can get away with making a smaller circle that distorts less with the curvature of the bottle. However, I think most customers can see what's at play and not be confused. They know it's a curved surface.