My Nonna had some old Kodachrome slides she asked me to “develop at CVS”. Obviously CVS couldn’t do this so I tried scanning them, but because light needs to be shining through them from the other side, so they just come out black instead. Other guides suggested making contraptions on top of your scanner to reflect the light back down, but these did not work well for me.
There are expensive scanners you can buy for this purpose, or remote services you can send the slides to, but for just 2 slides I wanted to see if I could do something cheaply myself.
I ended up building this contraption, where I made my computer screen almost completely white (fullscreen TextEdit), hung the card a bit in front of it, and then took a picture with a nice camera.
The results were excellent!