Canon 55-250 f/4-5.6 IS - bad copy?

Drake · Apr 7, 2015

Few days ago I bought a used Canon 55-250 IS (mk1). Visually the lens seems to be in perfect condition, nothing indicates it was used at all.

After shooting a few sample shots I am kind of surprised. It's very sharp in the 55-135 range, especially for a lens this cheap, but there are some serious problems starting from 150 mm. The center is pretty sharp but the borders are very soft. But not in a way it usually happens in a lens (round pattern starting from the center, soft corners), more like a linear gradient (sharp in the center, soft to the left and/or right). You'll see what I mean when you look at the samples. It pretty much looks like one of the lens was not aligned properly with the rest, but it changes ftom picture to picture. It happens in nearly every photo, and stopping the lens down doesn't seem to be making a huge difference.

I tried everything: shooting with IS on/off, phase detection (it's interesting that most of AF points light up, even the ones on the edges), contrast AF, according to the camera there's no issue with focusing.

I understand you can't expect perfect IQ from a cheap, plasticky tele mounted on a Canon 1000D, but the even cheaper Sigma 70-300 I used to have was way better in every situation.

Here are a few sample shots, full size jpgs exported from LR with default settings:

163mm, f/5.6, ISO 200, 1/800 s
IMG 0400.jpg - Google Drive

154mm, f11, ISO 200, 1/160 s
IMG 0414.jpg - Google Drive

194mm, f7.1, ISO 200, 1/400 s
IMG 0461.jpg - Google Drive

200mm, f8, ISO 200, 1/200 s
IMG 0450.jpg - Google Drive

More sample images
Canon 55-250

Is it normal for this lens or did I simply get a very bad copy?

Microbois · Apr 7, 2015

I don't have any experience with this lens, but one good way to find out if it's a common problem with this lens is to do a Google search with the following keywords "Canon 55-250 f/4-5.6 IS review".

Derrel · Apr 7, 2015

Yeah, I am thinking "decentered lens element" is the culprit....I dunno...it's very poor at the edges of the frame, and has that weird, jittery, looking-through-1-inch aquarium-glass look to the areas off to the outer parts of the images. The test shots you did, I looked at all the ones here, and four on Google+...wow...just not right... The central core images area is very good to excellent...the edges SHOULD be much better at f/7.1 and f/8 than they are. Instead of just a normal, slightly-softer-than-center look to the edges, there is that weird, "nervous", "jiggly" look that makes me think the lens has a decentered element. Maybe it is a problem with the Image Stabilizer lens group, I do not know, but I have a friend, Sally, who has this same lens, and it looks better than this on her pictures.

Your description is appropriate: the central area image quality is very good to excellent, but then the image quality plummets to very poor, in a very sharp, distinct "break", and that as you say, is not the normal way.

TCampbell · Apr 7, 2015

Yep - I was never impressed with my copy of the old EF-S 55-250mm f/4-5.6 IS lens either. At lower focal lengths it was fine... at higher focal lengths I was never impressed. I ultimately gave my copy away to a nephew who had a Rebel, but just the 18-55 kit lens.

The images can be improved using a "levels" adjustment to improve overall image contrast, but pixel to pixel contrast and detail resolving power ("accutance") was never very good at higher focal lengths. You can apply some sharpening to the image to get some improvement.

This is one of those trade-offs of lenses. The newer EF-S 55-250mm "STM" version is significantly improved (nothing that competes with the high-end glass, but significantly improved over what the older 55-250 lenses could do.)

beagle100 · Apr 8, 2015

TCampbell said:
Yep - I was never impressed with my copy of the old EF-S 55-250mm f/4-5.6 IS lens either. At lower focal lengths it was fine... at higher focal lengths I was never impressed. I ultimately gave my copy away to a nephew who had a Rebel, but just the 18-55 kit lens.

The images can be improved using a "levels" adjustment to improve overall image contrast, but pixel to pixel contrast and detail resolving power ("accutance") was never very good at higher focal lengths. You can apply some sharpening to the image to get some improvement.

This is one of those trade-offs of lenses. The newer EF-S 55-250mm "STM" version is significantly improved (nothing that competes with the high-end glass, but significantly improved over what the older 55-250 lenses could do.)