With thanks to Lewis, I can now compare an ED triplet Super Apochromat to a CaF2 Doublet apochromat on my "Blink Comparator"
In the left corner, weighing in at a moderate 5400 grams..... the Takahashi TSA102S with Ohara FPL53 ED glass ........... and in the right corner at a rather svelte 4300grams..... the Takahashi FS102NSV sporting the Canon Optron CaF2 Fluorite Crystal..... Being that both are 102mm F8 instruments with the beautiful EMS-ULS Silver mirrored visual backs and Takahashi eyepieces, it should be a good fight....
Lets Rumble