Unity Compressed Image size limitations

We are using PNG sequence sprites. Some of which we have gone to the trouble of getting down under 10 kb an image at 256 by 256. However, in unity, when compressed to a 16 bit rgba image, these files are 128 kb. This 128 kb size seems independent from the initial png file size. That is, a 100 kb 256 by 256 png when compressed is also 128 kb.

What does this mean? What benefits do we get by using a smaller file size when this is the case? Should we be maximizing our image quality under 128 kb instead of reducing image size and quality? Any help would be greatly appreciated.

 

Don't even have a look at the image's original file size, because it is unrelated to what you are going to get in Unity. What is important is the final image quality and the final image's occupied space. Work based on that and forget about the initial image file size.

If you are directly modifying the original file, it is better to work with a png than with a jpg, as you will continuously loose a little image quality with jpg if you are using the compressed one.