35mm slide holder / scanner

This is a contraption I designed to allow me to very quickly scan thousands of my parents 35mm slides. The slide drops in the small slot, put your phone in the back slot and have your phone display a white screen at full brightness (there are several free apps that can do this). Then use your dslr with an appropriate macro lens to copy the slide. I use a panasonic GH5 and a sigma 105mm macro lens. I set the camera to aperture priority mode at f8. I also enable the HDR mode in the menu to ma