I have tried everything I can think of, but when I reduce resolution of graphics, keeping the same dimensions, it has no effect on the size of the file.
This makes no sense. I prepare graphics for the web and so I often want to drop some weight by lowering the resolution of an image from, say, 300 ppi to 72 ppi. It would seem, intuitively, that this would lower the size of the file. Yet, when I do it, the file size stays the same.
Is there something I’m missing? I’ve tried with resampling on and off, to no avail.
If you’re using a set amount of pixels, let’s say 500 x 500, it won’t matter whether you’re using 300 ppi or 72 ppi because the amount pixels in the image would still be 500.
If you wan’t to lower the file size of your image you will either need to scale down the image or save the image in a lower quality format:
Save for Web as this can give you a finer degree of tweaking with your image quality as you save: