I've been trying to figure out an alternative to the traditional 18-55 kit lens as a walking around lens for my 77D. I feel that the high resolution sensor is terribly limited by the low resolution of the old kit lens. I tried a recently manufactured kit lens to see if perhaps my 10 year old version was worn out, but didn't see much improvement. I also have the 18-135, which is better, but still not as sharp as I feel the sensor deserves.
I checked out my options and decide to try a Canon EF-S 15-85 IS. On Amazon a new copy with USA warranty is $799 and a Canon refurbished copy is $599. I didn't want to spend that much for this lens, so I looked at used lens options. I ended up getting one from MPB.com for $299. They had three copies in different conditions. I picked the middle one which I think was labeled "good." I inspected it on arrival this morning and it looks almost new to me. It was in an original Canon box, for whatever that's worth.
I immediately tested the focus accuracy and found that it was not front or back focusing. Frankly, it's not that important on a lens with a max aperture of 3.5 to 5.6, but I have a focus accuracy complex that demands respect.
Then I put up a resolution target and shot side by side comparison images with the 15-85 and the 18-55. Both zooms are at 55mm on a tripod with strobe illumination. Both were taken with the aperture wide open. The 15-85 was at F/5 and the 17-55 was at F/5.6.
The two images below are as close as I can get to a 1:1 export with Lightroom. Normal sharpening was used. This is a pretty quick and dirty resolution test, but I think the results are pretty clear.
This one is the 18-55 kit lens at F/5.6:
This one is the 15-85 at F/5:
You would not confuse either of these images with something from a full frame camera with an L lens, but I think I'm going to be reasonably happy using the 15-85 as my walk around lens. It is bigger and heavier, but if I want light and compact, I will use the excellent 24mm pancake lens rather than the kit lens.
I checked out my options and decide to try a Canon EF-S 15-85 IS. On Amazon a new copy with USA warranty is $799 and a Canon refurbished copy is $599. I didn't want to spend that much for this lens, so I looked at used lens options. I ended up getting one from MPB.com for $299. They had three copies in different conditions. I picked the middle one which I think was labeled "good." I inspected it on arrival this morning and it looks almost new to me. It was in an original Canon box, for whatever that's worth.
I immediately tested the focus accuracy and found that it was not front or back focusing. Frankly, it's not that important on a lens with a max aperture of 3.5 to 5.6, but I have a focus accuracy complex that demands respect.
Then I put up a resolution target and shot side by side comparison images with the 15-85 and the 18-55. Both zooms are at 55mm on a tripod with strobe illumination. Both were taken with the aperture wide open. The 15-85 was at F/5 and the 17-55 was at F/5.6.
The two images below are as close as I can get to a 1:1 export with Lightroom. Normal sharpening was used. This is a pretty quick and dirty resolution test, but I think the results are pretty clear.
This one is the 18-55 kit lens at F/5.6:
This one is the 15-85 at F/5:
You would not confuse either of these images with something from a full frame camera with an L lens, but I think I'm going to be reasonably happy using the 15-85 as my walk around lens. It is bigger and heavier, but if I want light and compact, I will use the excellent 24mm pancake lens rather than the kit lens.