I’ve used a scanner that came with a slide holder specifically to scan slides. Use the highest possible resolution when scanning. If the resulting image is too small to work with, check out Topaz Labs’ Gigapixel AI. It will uprez a file up to 6 times the original resolution, at the same time correcting for noise & blur. The results are great. Most times, the uprez looks better than the original. I own a number of Topaz Lab programs. They have free trials, so you can check it out before purchasing. Also, they constantly update their models every few months, so the results keep improving.