2. 'L Quality' doesn't have any meaning.
2. Disagree - pick up a 17-55 and a 24-105, or a 50/1.4 and a 50/1.2L, and 'L build quality' is obvious.
Yeah, but pick up any of the fast USM primes and say a 200 f2.8 or 135 f2.8 and the difference isn't so apparent.
The L's are properly designed as tools for a given job, so it's not to be unexpected that they have individual characteristics, some are state of the art and have everything that could be reasonably expected from a lens by a working professional. Others are robust precision tools with the money spent where it matters rather on redundant features like say AF on a TSE or IS on a fisheye...
My gripe is not about the general greatness of L lenses and the expectation that the red ring rightfully inspires, it's just that as a parameter of comparison, it's not the greatness, it's the general bit that bothers me.
To decry a budget lens ('gateway' was spot on) as being or not being 'L quality' just isn't all that useful.
It's blind submission to marketing speak.
I've came up with two things for my list...
1. Red Ring
2. EF mount
Dang, there are other lenses with EF mounts that aren't L's.
Sheeeeeet (to quote Clay Davis)
1. Red Ring.
I'm aware I'm being a boring pedantic pr1ck here. I just don't know what L quality means. Well I do. But really, literally, we don't. Canon doesn't. As their EOS Works statement belies.
It shouldn't be so easy a thing to say, if it isn't so easy to define.
And it shouldn't really be applied to a lens like the 55-250 STM in any terms. It's just not helpful at all to anybody.
There are a ton of aspects to a lens that aren't simply covered in an MTF chart.
1. Build quality (metal v. plastic)
2. Weather sealing
3. Aperture variable v. constant regarding zooms.
4. Max aperture
5. Sharpness @ center and at edges
6. Color replication/saturation
8. Chromatic abberation
9. aperture design (round v. hexagonal)
11. barrel distortion
12. full time manual focus
13. auto focus speed
14. bokeh rendering
Every lens is a sacrifice. We are dealing with the properties of bending and capturing light. And while "L Quality" may be a vague term, you can often say that many of the 14 should be an improvement over the non-L counter part.
There are too many smart people in these threads and photographers in general who would be swayed by branding and advertising.