On standard zooms, they aren't terribly part apart if memory serves, perhaps 1-2 mm or so? But on longer glass the differences can be quite pronounced.
Speaking in mm focal length this is correct, but the effect of +-1 mm on a wide angle lens has much more impact than 10 or 20mm on a tele zoom. You can always crop in a little, but you cannot restore data if your lens wasn't wide enough. That's why I'm currently happy with my 17-40L, even though you might say the 17-24 range isn't such a big deal in objective terms.
Yeah, agree. On the wide end, 2mm is a huge deal. Many people prefer the slower 15-85 EF-S lens over the quicker 17-55 EF-S solely because of that key extra width. And a number of landscape guys still haven't forgiven Canon for yet offering another 16-35 when they were screaming for a 14-24.
The extra 2 + the extra 30 + I think its better glass... on the other end the you can work around 2.8 on an all purpose zoom
The reason I bought the Canon 15-85mm, is that for my style of photography it is a great balance in a useful focal length zoom, while retaining high image quality. I find the 17-50/55mm or the 18-55mm lenses just miss the mark in terms of what I like for a walk-around zoom. Plus when I want ‘fast glass’ – I don’t want f/2.8 (I consider that ‘moderately fast’) – I need to go for f/1.4 – f/2.
In terms of this rumour of an UWA EF-S 11-24 from Canon – I just can’t see how it ‘fits’. The EF-S 10-22mm USM continues to be a well performing, decent selling UWA. Then the recent 10-18mm IS STM is a great budget option (with superb bang for one’s $!). And the EF-M 11-22mm IS well, that’s proven to be a great lens for EOS-M.
Yes, I love UWA… and that’s why I upgraded from to the Sigma 8-16mm HSM… it’s an awesome lens for APS-C cameras. The only real ‘handy’ improvement would be to add OS (stabilisation). But the difference from 10mm (which I was previously limited to) to 8mm really makes a big difference, (cf the difference from 12.8mm to 16mm in FF format).
While we’ve got great choice in UWA’s for APS-C already, here’s hoping more great quality UWAs are in the pipeline from various manufacturers!