The "S" lenses are six element in 4 groups. The E are not as well designed and cost less.
Brochure is wrong, they mixed up elements and groups. The box in which the lens is shipped correctly identifies the lens as 6 elements and 4 groups.
I started to write an article about the Komuranon-E lenses late last year but didn't have enough info to publish the page. Yesterday I published it inadvertently when I updated various other pages so I've left the page up (and uploaded the attached images and properly added it to the index page too).
It doesn't add much to the question about these lenses and is a work in progress. I will add to it as I get credible info. But my suspicion is that the E and S lines are identical bar possible coating differences, but presently this is only conjecture on my part so not worth a pinch of anything.
I've seen (and have the image but can't post it because it's not mine) the box for a Komuranon-E 5.6/75 which states it is 6E-4G, ie same as Komuranon-S 5.6/75. The E and S lenses that I have appear to be of the exact same build (I haven't compared coatings) although I don't have E-S pairs to compare directly (I have a pair of S75, a pair of E50, a pair of E105 and they all look and feel the same).
I've seen (and have the image but can't post it because it's not mine) the box for a Komuranon-E 5.6/75 which states it is 6E-4G, ie same as Komuranon-S 5.6/75. The E and S lenses that I have appear to be of the exact same build (I haven't compared coatings) although I don't have E-S pairs to compare directly (I have a pair of S75, a pair of E50, a pair of E105 and they all look and feel the same).
Yes I think you are correct and I was wrong. I did find this picture with the "E" box showing "6 elements". I only have an "S" but no "E" to compare side by side.
The Leica dealer I bought my first (!-I now have 6!) 50m S from said the S was in another class up than the E. I bought an E a couple yrs ago to test against the S but haven't been able to do so. They look identical, but who knows about the glass? The S is very similar to the late Leitz Focotars, by the way! Chip