Unity image is blurry after using long image

As shown in the picture, I assign a long image to the image and then it is very blurry. It is very clear when double-clicking to open the image

Solution:
Select image Default—MaxSize resolution to maximum

Reason analysis, the resolution of the picture itself is more than 10,000, when used in unity, the resolution is set to 1024, so it leads toBlur, when the resolution is adjusted, it will be clear.
Disadvantages: The higher the resolution, the more memory the image takes up. For example, my long image, the resolution of 1024 is only 360.0KM, and when it is adjusted to the resolution of 8192, it is as high as 22.6MB, a picture occupies dozens of MB, which is too large,