I've been musing a lot about lenses lately, & I've a hypothetical question for the lens design experts out there:
What would a wide-aperture EF-s kit zoom look like?
The idea is to introduce the consumer to the concept of wide-aperture lenses like we had in the days when the 50mm f/1.8 prime was considered the "kit" lens, while still being the cheap consumer zoom so apparently near & dear to Canon's marketing people over the last 15 years.
My thinking is the following:
- Unlike Nikon, Sony, u4/3, etc, Canon's basic prime lineup is older than Methusalem. It is highly unlikely that they'll release any updates to any of the old "consumer prime" designs.
- New Canon EF-s plastic zooms, however, are released almost every year.
- Several patents for wide-aperture zooms give us hope for something different.
With the possible (hopeful) exception of an EF-s 30-ish prime, it's pretty clear that anything Canon releases to "replace" the old primes will be a zoom. Digging into this patent
, we see specs for two 2x zooms: a 24-48 and 25-50, both f/3.5-4.8. Notice that they're in the same patent that features a lot of new tricks with DO elements and fast wide primes. But I also get the feeling that these are all pro-grade full-frame designs.
Basically my idea is a cheap plastic wide-aperture 2x zoom with all the cost-cutting features of the 18-55 kit zoom (rotating front element, external zoom & focus, etc), but it would also have consumer-grade USM & IS. A 22-44mm EF-s zoom for example (they'd probably call it a 22-45) would be the equivalent of a FF 35-70, and line up nicely above the EF-s 10-22. 22mm is a pretty conservative retrofocus focal length on EF-s...
My question is, could they design such a thing with a wide enough aperture to really differentiate it from the other EF-s zooms and come close to replacing the "consumer" wide prime lineup on the EF-s platform, & still keep it cheap enough to offer as an optional kit lens? I'm thinking something along the lines of f/2.8-3.5 (constant f/2.8 would be great but is probably too ambitious). They've done lenses in the past like the 28-105 f/3.5-4.5 USM (and plenty of other f/3.5-4.5 zooms), so wider-aperture variable zooms aren't unprecedented.