It is difficult to understand why most companies scan 126mm slides but scan them in a 35mm format. When you take a square and make it a rectangle it does not work very well. Your slides will be cut off on the top and sides. Most slide scanners do not crop these properly, they need to be scanned with a custom setting. We will scan your 126 mm slides correctly. If you are not sure what these slides look like, they are a square negative/positive framed in the 2×2 inch mount. The 35mm slide is a rectangle negative/slide mounted in the same 2×2 cardboard or plastic mount. This was a popular film size in the 1970s when the Instamatic Cameras were popular.