Lens playing up - help needed

[mammarazzi]

Hi Folks,

Have had a Canon EF-S 55-250mm 4 - 5.6 IS lens for about 15 months. Working fine but all of a sudden it will not auto focus properly. At the bottom end 55mm it is fine and the pictures are clear but the moment you increase the zoom, even though the auto focus bleeps to tell you that it is in focus the pictures are slightly blurred and the longer the focal length the more blurred they become.
Has anyone else had this problem? Does anyone know what might be wrong? Is it repairable or just get another lens? (maybe treat myself to a better quality lens).
Your help would be very gratefully recieved.

Joanne

[rpcrowe]

Joanne, I have not personally worked with the 55-250mm lens but, usually when a lens is having focus problems I usually recommend:

1. Cleaning the contacts...

2. Ensure that the camera battery is fully charged...

2. Troubleshoot by trying the lens on another camera and/or trying another lens on your camera. That should isolate whether it is your lens or the camera or a combination of the two at fault...

Finally, if all else fails, contact the Canon Service Center in your area and discuss the problem with them.

Here is a site which should provide address and phone number of your closest service center

http://www.canon.co.uk/Support/consu...tor/index.aspx

I know how frustrating it can be to have equipment acting up... Good luck!

[Andrew1]

The only time I've had a problem with zoom lenses is in reduced light. The longer the focal length the less light is able to get to the sensors. Once you have cleaned the contacts and made sure the battery if fully charged, try the lens outside in bright light. While there still may be a problem with the lens in reduced light at least you will have more information to work with. Check with one of the UK repair centers to see if there is a minimum charge just for inspection and estimating the repair. Your lens in one of the more economical to replace and it may be cheaper to do that.

[Geoff F]

I'm assuming, Joanne, that you have tested it on a tripod and it isn't something basic like having too slow a shutter speed; possibly caused by incorrect camera settings.

Some time ago, I had a slightly similar experience with a cheap lens, which I bought attached to a secondhand camera. In that case, it worked OK at the small end but the exposure failed to operate as I zoomed.

Unless it is a problem with poor contacts, etc, my advice would be to 'convert it into a doorstop and get something better'. UK Canon authorised repairers charge at least £100 for a strip down and rebuild plus any new parts.

So I would put that money towards a replacement 70-300 IS or, if you can afford at least twice the price, a L lens alternative.

[victor]

Just had the aperture fail on my 18-85 efs zoom. Cost £135.00p. Worth having the lens checked over.

Regards

Victor

[Carl in Louisiana]

So I would put that money towards a replacement 70-300 IS or, if you can afford at least twice the price, a L lens alternative.

If you decide to go with the 70-300 IS, I just picked mine up it was a factory demo and factory refurbished lens. WOW it is like brand new and I am really amazed at how well it works. The IS on this one does not make any noise at all unlike the reports in reviews that I have read on it. The place I bought mine had nine left and was charging $364.95 + $10.00 shipping. I think I remember seeing that they shipped over seas not sure if it would be feasible.

[inkista]

... the pictures are slightly blurred and the longer the focal length the more blurred they become...

Just one question: what's the nature of the blur? Is it "smeared" or like a ghost image? Or is it overall fuzziness? Because if it's the former, it could be that you're running into a shutter speed issue. Camera shake can cause blur at lower shutter speeds, and the longer the lens, the more this blur will register. A lot of folks mistake it for a focus issue or softness in the lens.

The rule of thumb (and I will stress this is only a rule of thumb, not hard and fast. Some folks can go slower, some folks throw in the crop factor or double the speed), for someone holding the camera correctly (i.e., left hand supporting the main weight of the body/lens combination from below, palm up), with a good solid stance and technique is that the shutter speed should be 1/focal_length or faster. IS can help mitigate this restriction, but it will only help so much (1 or 2 stops, for me), and is not the same as using a tripod.

So, with the 55-250 IS, if you're @250mm, your shutter speed should probably be at 1/250s or faster to be super-safe, and maybe down in the 1/150-1/60s shutter speed range if you're really good at holding the camera steady.

In addition, most consumer zooms, like the 18-55 kit lens or the 55-250 IS, will benefit from being stopped down at least one stop from wide open. Which, in this case, would mean using f/8.

Naturally, being restricted to f/8 and 1/250s or faster means you need a lot of light or a very very high iso setting to get a good exposure.

[William W]

At the bottom end 55mm it is fine and the pictures are clear but the moment you increase the zoom, even though the auto focus bleeps to tell you that it is in focus the pictures are slightly blurred and the longer the focal length the more blurred they become.

In any case - a sampe image with EXIF data would assist, please.

***

maybe treat myself to a better quality lens. . . Your help would be very gratefully recieved.

I suggest you get to the bottom of the issue rather than running out and buying a new lens as your knee jerk solution.

I have found that the EF-S 55 to 250 IS F/4~5.6 is a surprisingly good performing lens.
We have been running one for about three years and also bought a second a few months ago.

For example - this controlled comparison suggests that the EF-S 55 to 250 IS F/4~5.6, is superior in most regards to the EF70 to 300 IS F/4~5.6 USM, when both are used on an APS-C Camera.

Most notably the EF-S lens performs much better at both extremes of the Zoom Compass, with the Aperture wide open – which is more notable considering the larger Image Circle of the EF lens.




WW

[rpcrowe]

This is not exactly in line with your post but, it is connected. If you decide to get a reasonably priced 70-300mm f/4-5.6 lens with motion compensation; there seems to be basically two choices: Canon 70-300mm f/4-5.6 IS and Tamron 70-300mm f/4-5.6 VC.

I have used neither of these lenses but there is one glitch with the Tamron. Apparently (I may be wrong) it doesn't have a motion compensation mode compared with Mode 2 of the Canon lens. The Mode 2 allows image stabilization when panning. I use this very often and would not want a lens that I cannot use to pan with the IS turned on. I recently did some panning and forgot to switch to Mode 2. The results were images not quite as good as usual, when I panned in Mode 2.

If you want a really great telephoto lens, any of the Canon 70-200mm L (series) lenses provide exceptionally good image quality and accurate fast auto-focus as well as a constant aperture through the focal range. Of course, the prices of these lenses are prety expensive.

There are many threads touting the benefits/shortcomings of these lenses... I have owned the 70-200mm f/4L (non-IS) version and presently own the IS model. I use the IS version 4-5x more often than I was ever able to use the non-IS lens because I can hand-hold the lens in lower light.

The three f/2.8L lenses are also excellent. However, they weigh considerably more than either f/4L lens.

I am thinking that an f/2.8 aperture at 200mm or thereabouts would allow you to really blur the background of your excellent field sports images.

There is also the 70-300mm f/4-5.6L IS lens which many photographers seem to be quite happy with.

[mammarazzi]

Thank you all for your replies. I have cleaned contacts, checked switches, taken photos in bright sunlight but as soon as I extend a fraction you can hear the motor working quite hard (longer than normal)when I press the shutter button half way to focus. It then bleeps when it has found focus but the images are still not crisp. I did not pay very much for this lens so I think I might treat myself to a new lens and keep this one just using the manual focus.
I found my 100-400 L USM with a cracked UV filter (thank goodness I had it on and the lens works fine) so I think one of my lovely kids has knocked my camera bag over or dropped it possibly damaging the 55-250 lens.....no one is owning up!

[Geoff F]

Sounds like you have a Nanobot infestation there Joanne!

Nanobots were originally invented secretly by NASA as miniature robots for the auto repair of spacecraft; but some escaped from the laboratory and mutated in the wild into an extreme Gremlin like organism.

They strip down anything mechanical then rebuild it in another place. Which is why somethings disappear then reappear a few days later in a different place.

But because of the mutations, the rebuilds often don't work properly.

So your lens wasn't accidentally dropped by a member of your family - it's all due to the Nanobots!

Well it makes a good story!

Reviews of that lens often state that the optics are surprisingly good for the cost, but the build quality is rather poor. Built to a price I suppose.

If you can afford to purchase something slightly stronger, that is the way I would go. And put what the repair would cost towards the new lens. So it doesn't actually cost quite so much does it!

Keep thinking that way.

[William W]

. . . as soon as I extend a fraction you can hear the motor working quite hard (longer than normal)when I press the shutter button half way to focus. It then bleeps when it has found focus but the images are still not crisp. . . I found my 100-400 L USM with a cracked UV filter (thank goodness I had it on and the lens works fine) so I think one of my lovely kids has knocked my camera bag over or dropped it possibly damaging the 55-250 lens.....no one is owning up!

This added information is significant.

The 55 to 250 is certainly not as robustly built as the 100 to 400L and an impact could certainly result in operation error.

If it the lack of AF acquisition is a result of Physical Damage I expect the repairs might be more than sourcing a second hand version in good working order.

Considering you have a 100 to 400 (but without knowing your other lenses) - it occurs to me that a 70 to 200L IS, would be worth considering as a replacement.

WW

[mammarazzi]

I thought NanoNano was from Mork & Mindy