hmm I am guessing you are just starting GFX
why? because a GFXer knows when a signature or picture looks stretched.
One thing to keep in mind is to make sure your pictures look high quality. What do you mean? make sure you are using png not jpg and if you are resizing pics make sure their size from height to width are resizing as well at the original proportions. what?
when resizing make sure both height and width are resizing at what ever pixels you are using.
If you are using GIMP or PS make sure you play around with the adjustments
made a little GFX logo
View attachment 738795