100mm 2.8 Macro Not focusing

[swanphototx]

My macro lens is constantly hunting for a focal point. It has recently started this and no matter if I'm using it for ring shots or portraits, good lighting or bad, it won't focus.

It's never been dropped or damaged. I've had it for almost 5 years. 

[Waddizzle]

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@RobertTheFat wrote:

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@FamousEdOwen wrote:

I have a canon rebel xs with the 18-55mm lense and is doing the same thing.  I can manually focus and the red lights show when I push the button half way in.  When I have it on auto focus it just keeps going in and out.  Sporatically it will find focus and stop but most of the time it goes on for as long as I hold the button in.  I have 3 other lenses and these all work fine so i know it is in the lense, not the camera. 

I hope it's okay to jump on someone else's post.  I didn't see any more replies and was hoping for an anserw since I have yet to find any others with the same problem.

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Unlike the situation with the OP's macro, this sounds like one of those cases where the autofocus motor got stuck. The usual cause is trying to focus manually while the lens is in AF mode. The cure that often works is to forcibly manhandle it back into position. Obviously this requires a certain degree of finesse, but the procedure has been described several times in the forum. I can't tell you exactly where to look, but I don't doubt that one of the other regulars will be able to help you. (If I'm right about the cause!)

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This might be the one.

http://community.usa.canon.com/t5/Lenses/Autofocus-not-working-18-55mm-lens/td-p/138114

[ebiggs1]

I guess the "second" OP can try that.  It won't help!  I don't think it will work or is the problem but, hey, it's free to try.  I never heard of the ef 100mm f2.8 macro suffering from that problem.  Of course that doesn't mean anything.  Does it?   Better option is to call Canon Service.

Remeber, the lens never knows when it is in focus, the camera does!

[RobertTheFat]

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@ebiggs1 wrote:

I guess the OP can try that.  It won't help!  I don't think it will work or is the problem but, hey, it's free to try.  I never heard of the ef 100mm f2.8 macro suffering from that problem.  Of course that doesn't mean anything.  Does it? ...

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In this case, no. But remember: we've deviated from the title of the thread. This latest inquiry is regarding an 18-55mm kit lens.

[Waddizzle]

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@RobertTheFat wrote:

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@ebiggs1 wrote:

I guess the OP can try that.  It won't help!  I don't think it will work or is the problem but, hey, it's free to try.  I never heard of the ef 100mm f2.8 macro suffering from that problem.  Of course that doesn't mean anything.  Does it? ...

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In this case, no. But remember: we've deviated from the title of the thread. This latest inquiry is regarding an 18-55mm kit lens.

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This thread is a textbook example of why people with people should always start a new thread for their new problem, most especially if it is the same problem [which in this case is not] as the original thread.  It makes it easier to search the forum for solutions, and then Actually find the answer.  Who wants to read a thread with 112 replies, and most don't apply? 

[RobertTheFat]

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@Waddizzle wrote:

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@RobertTheFat wrote:

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@ebiggs1 wrote:

I guess the OP can try that.  It won't help!  I don't think it will work or is the problem but, hey, it's free to try.  I never heard of the ef 100mm f2.8 macro suffering from that problem.  Of course that doesn't mean anything.  Does it? ...

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In this case, no. But remember: we've deviated from the title of the thread. This latest inquiry is regarding an 18-55mm kit lens.

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This thread is a textbook example of why people with people should always start a new thread for their new problem, most especially if it is the same problem [which in this case is not] as the original thread.  It makes it easier to search the forum for solutions, and then Actually find the answer.  Who wants to read a thread with 112 replies, and most don't apply? 

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Add to it that it had been four months since the original topic petered out and that the current inquirer used the same icon as the last contributor to the old topic. It's easy to see why Ernie got confused.

But the old topic and the new topic did share the same symptom (AF not working). So I can see why the current inquirer thought he was continuing the same topic.

[Waddizzle]

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@RobertTheFat wrote:

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@Waddizzle wrote:

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@RobertTheFat wrote:

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@ebiggs1 wrote:

I guess the OP can try that.  It won't help!  I don't think it will work or is the problem but, hey, it's free to try.  I never heard of the ef 100mm f2.8 macro suffering from that problem.  Of course that doesn't mean anything.  Does it? ...

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In this case, no. But remember: we've deviated from the title of the thread. This latest inquiry is regarding an 18-55mm kit lens.

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This thread is a textbook example of why people with people should always start a new thread for their new problem, most especially if it is the same problem [which in this case is not] as the original thread.  It makes it easier to search the forum for solutions, and then Actually find the answer.  Who wants to read a thread with 112 replies, and most don't apply? 

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Add to it that it had been four months since the original topic petered out and that the current inquirer used the same icon as the last contributor to the old topic. It's easy to see why Ernie got confused.

But the old topic and the new topic did share the same symptom (AF not working). So I can see why the current inquirer thought he was continuing the same topic.

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You're also overlooking the biggest problem with hitchihiking onto an existing thread.  The OP who started the thread is quite likely getting a host of email notices related someone else's problem, and not their own.

[RobertTheFat]

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@Waddizzle wrote:

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You're also overlooking the biggest problem with hitchihiking onto an existing thread.  The OP who started the thread is quite likely getting a host of email notices related someone else's problem, and not their own.

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I doubt that. My experience is that posting in this forum doesn't generate email traffic for the poster. A poster's email address isn't even made readily available.

[Waddizzle]

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@RobertTheFat wrote:

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@Waddizzle wrote:

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You're also overlooking the biggest problem with hitchihiking onto an existing thread.  The OP who started the thread is quite likely getting a host of email notices related someone else's problem, and not their own.

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I doubt that. My experience is that posting in this forum doesn't generate email traffic for the poster. A poster's email address isn't even made readily available.

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???  It's called subscriptions. 

You can subscribe to email alerts whenever someone replies to thread you've replied to.  You can set it up so that every thread you reply to is automatically subscribed, or not.  Check the "Topic Options" tab at the top of the thread.

[RobertTheFat]

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@Waddizzle wrote:

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@RobertTheFat wrote:

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@Waddizzle wrote:

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You're also overlooking the biggest problem with hitchihiking onto an existing thread.  The OP who started the thread is quite likely getting a host of email notices related someone else's problem, and not their own.

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I doubt that. My experience is that posting in this forum doesn't generate email traffic for the poster. A poster's email address isn't even made readily available.

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???  It's called subscriptions. 

You can subscribe to email alerts whenever someone replies to thread you've replied to.  You can set it up so that every thread you reply to is automatically subscribed, or not.  Check the "Topic Options" tab at the top of the thread.

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Yeah, I guess I've had threads set up that way in the past, but I'm not sure I have any set up that way now.

But I think we're starting to get wrapped around the axle over a non-issue. Yeah, the current poster replied to an old thread because the symptoms looked similar. They probably weren't, but that's hardly the point. The mistake was easy to make because the messaging program makes no effort to warn you that you're replying to an old thread. Indeed, modern messaging systems appear to behave that way on purpose. Note that in this very thread the date on which a message was sent is displayed in a very light gray font that's intentionally hard to read. I don't know why they do that, but what I do know is that calling out a poster for not noticing that a thread is stale is arguably a form of blaming the victim.

[ebiggs1]

"... clean the lens contacts carefully ..."

The only good thing about cleaning the contacts is, it is 'mostly' free, so it is worth a try.  It rarely to never helps or works.