Still, at first glance you'd think an 11/9 lens is going to be harder to engineer, assemble, and QC than a 8/6. But I can believe the opposite might ironically be true in some cases.
This is utterly true. I don't think anyone was complaining about the EF 50mm 1.8 1.4 and 1.2 when they were all new. And yet they're simply not acceptable now, you almost might as well use a smartphone. (People complained about the 50/1 from day one but in the context of its ability were willing to accept it.)
On one hand its cool, but on the other it may be what's making the 35 the extra 10-15-20mm longer than I'm willing to carry in my backpack all day every day just in case. Just to be clear I'm hoping for a 28, 35, and 50 that is no more than 35mm long (past the flange) so that it it sticks out at most as far as the grip. I'd sacrifice IS and macro to get it. I also require it to be f/2 or bigger, so that it gives me some kind of capability that even trinity zooms don't. I don't want a lens that is portable, but useless when I have the full kit...
Canon uses automated machines to build a lens from scratch. I'm not sure if the RF lenses are automated but I suspect they are. It's certainly something Leica does not do
If the RF 35mm 1.8 can be used as a measure, the 50mm 1.8 and the 50mm 1.4 MTF's aren't even in the same league wide open. It's not even close.
Comes down to what the lens is designed for. As I mentioned before, the 50mm shown in this patent application is an average size for 50mm's being created for mirrorless these days.
It should also be noted that more modern Leica designs like the Leica Summicron-SL 35mm f/2 ASPH are not small either. Not even Leica has chosen to create a small mirrorless digital lens. (it's MTF's though are excellent).
I assume you are talking about the Leica Summilux-M 35mm f/1.4 ASPH, which really does need to be stopped down according to it's published MTF's which is probably why Leica decided to create a whole new lens design for the SL lens. Here's probably where we get into why it's smaller. Wide open the response it is simply an average lens, it would look good on film because you're not heavily magnifying the images as we do on digital, but it's not up to digital standards.
Here's the rub. We get into a simplistic triangle of lens design we have:
You can't have all three. Most times you can have 2 out of 3. Sometimes only 1 out of three. Some of the EF-M lenses are the closest I've seen Canon get to actually managing all three to be moderately good to excellent.
A pancake lens designed around a tessar optical design will probably be released by canon sometime - that's the lens you're probably looking for. Odds are it won't be faster than 2.8 (might be 2.0 though), and be around 20mm in focal length. Usually, for Tessar designs, the focal length is approximately the same as the distance from the sensor to the lens.
I should do an article on this. maybe next week.