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I recently purchased a used Canon 55-250mm IS lens and it works nicely at 55mm(even with lower shutter speed, and f/4 aperture), but turns out quite blurry at longer focal lengths, even with a shutter speed of 1/800, f/11 and while mounted on a tripod. I'm not sure if this is a user error, or something wrong with the lens. Any ideas?

MikeW
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Tristan
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  • Can you use manual focus or Live View to get sharper results at focal lengths past 100mm? – Michael C Jan 08 '15 at 13:32
  • I've tried to use manual focus which produces a slightly clearer image in the center of the frame, but still seems poor and worse in the edges – Tristan Jan 08 '15 at 13:34
  • Picture at 55mm, handheld, 1/200, f/7.1, IS on (https://www.flickr.com/photos/130524019@N08/16044443647/)

    Picture at 250mm, tripod, 1/800, f/11, IS off (https://www.flickr.com/photos/130524019@N08/16228422741/)

     – Tristan Jan 08 '15 at 13:38
  • Have you stop the IS when mounted on tripod? – Romeo Ninov Jan 08 '15 at 14:27
  • @Tristan, switch focus to One shot – Romeo Ninov Jan 08 '15 at 14:36
  • At f/11 you are probably getting into some diffraction effects. The DLA for the T3 is f/8.4. But it still appears ur lens is under-performing at the long focal lengths. – Michael C Jan 10 '15 at 02:53
  • Where did you buy it? Is it a used or new item? I would definitely return it and ask for another one if you bought it new. – Ornello Jan 09 '15 at 17:54
  • Thank you all for the suggestions. It turned out to be a problem with the lens(the field curvature more specifically) and the seller has replaced it for me! Thank again. – Tristan Jan 15 '15 at 16:11
  • It seems that this is a problem with the lens. I haven't had this problem myself, but you can also get a similar effect if the camera shakes, even the slightest. Since you have it on a tripod, and with such fast shutter speed, shat shouldn't be a problem, though. – Cullub Feb 27 '15 at 17:08
  • Open the images in Canon ImageBrowser or Digital Photo Pro, and enable the focus point view. Ensure that your camera was focused on your subject. If not, that may be your issue: you are not focused on your subject – cmason May 15 '15 at 21:17
  • Voting to close as duplicate of Pentax DA L 55-300mm lens very soft--is it broken?. It's essentially the same issue affecting a very similar lens on a different camera system. – bwDraco Jun 15 '15 at 02:58

5 Answers5

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I see this is an old thread, but I have recently received a Canon 55-250mm IS II lens with this issue. All lens elements are clear, the zoom is smooth and the autofocus works well, but at 250mm the image is very blurry, improved a little by setting the aperture to f/32. Checked inside the front of the lens and the optical stabilizer lens looked off centre, then when removing the screws around the optical stabilizer, it moved back into centre as it should be. I reassembled the lens and it now works correctly again. It would appear it had a severe shock that caused the optical stabilizer lens to be stuck in an off centre position.

PeterS
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Your lens is damaged.

  • One of your images (shown below) exhibits an abnormal amount of spherical aberration. It is not the kind of softness you would get when out of focus. Also, notice that the bricks on the left side are significantly softer than the right side, which indicates decentering. Both of these indicate that one or more lens elements have been thrown off their correct position, most likely due to impact or shock (e.g. being dropped). (Note that dust spots are visible in your image which indicate that your camera's sensor needs to be cleaned.)

Linked image showing abnormal spherical aberration
View full size

  • Your lens needs to be repaired or replaced. Considering the low cost of the lens, the latter is probably the more economical option. I have personally dealt with this issue with a similar lens for the Pentax K system. See: Pentax DA L 55-300mm lens very soft--is it broken?
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bwDraco
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  • I have the same problem but worse, half of my right side of the images is blurred out the same way and a bit on the left too. I suspected it was broken but now I have something to tell the repair shop about what I think is wrong. Thank you bwDraco – Kristian Apr 09 '17 at 22:11
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That 250mm photo shows a distinct difference between the center and the edges. That looks definitely like a problem with thelens to me, i'd try to get it repaired.

ths
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  • I've done some more research about the lens and I've stumbled upon the MTF chart(http://www.usa.canon.com/cusa/support/consumer/eos_slr_camera_systems/lenses/ef_s_55_250mm_f_4_5_6_is) for this lens and the performance seems somewhat poor. Is the picture above what these specs should look like, or is this lens in particular preforming poorly? – Tristan Jan 08 '15 at 21:52
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    These aren't great lenses but you should be seeing better results. I'd suggest there are possibly misaligned optics, requiring a proper stripdown, service and rebuild. If there's a chance of a free repair from Canon then it's worth pursuing, otherwise you could be looking at spending more than the lens is realistically worth on repairs. Instead, I'd live with it for the moment and save up for a better lens such as the recent Canon EF-S 55-250mm f/4-5.6 IS STM, or even a second-hand 70-200 F4L (worth thinking about given its compatibility with full-framers like the 5D series)... – Darkhausen Mar 04 '15 at 13:18
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I think @ths is right, and you probably need to try to repair the lens. However, before you do that, the following might solve your problem, or at the very least will mean you've tried everything before you try a repair/replacement.

  1. On the tripod, is image stabilization turned off? I doubt this will make significant difference, but may be asked when taking for repair.
  2. Is autofocus turned on, on both the lens and body (if applicable)? If set to manual focus, the camera will obviously take the photograph regardless.
  3. Is focus mode set to continuous tracking? That is, if you keep the shutter release half pressed does the camera continue to focus even as it is moved?
  4. Are the front and lens elements clean?

These might be a bit basic, but just mean you have everything covered if you try to take your lens back.

Phil
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Based on personal experience, I'd say the 55-250 is best from 55-135mm and then the performance does drop off from there to 250mm. But having said that, the samples you posted indicated you are not getting close to the potential of this lens when performing properly. If there are no other issues present that could cause your photos to be blurry, then it appears there is a problem with your lens.

The following photos were taken with an EOS Rebel XTi (400D) and an EF-S 55-250mm f/4-5.6 IS II lens. They were resized to 1152x768.

ISO 800, 1/100 sec, f/5.6, 250mm f/5.6

ISO 200, 1/800 sec, f/10, 250mm f/10

When the full resolution version of the second photo is viewed at 100% there is some softness on the right edge of objects and people that are the same distance from the camera as the subjects that are clear. The AF was aimed at about the fifth row down from the top (the folks just in front of the guy in the white shirt). There is much less of the edge softness on the left edge of the frame.

Michael C
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