Would you leave one of the originals in each test visible at all times (a control) so that I can see the final image(s) that I'm considering and the original im

Would you leave one of the originals in each test visible at all times (a control) so that I can see the final image(s) that I'm considering and the original image at the same time? I guess if you do that then maybe you don't need the cool sliders anymore? Anyway - thanks so much for all your hard work on this. A very interesting study!