Lens not auto-focising

[chrisbroz]

First Post...Have a T1i I bought ca '09 - my standard lens is the 18-55mm.  I leave it attached all the time..lately (as in the past three or so months) the autofucus seems either to be, at best intermittent, or at worst, non-existent (and YES the switch on the lens is set to AUTO)...I left the focus setting on AI Focus and do the majority of my photography with the built in flash and for quite some time I've been getting out of focus results....after a while of this frustration I switched to AI Servo - it SEEMED to rectify the problem momentarily, but quikly reverted to the failure to focus problem....frustrated, I began manualy focusing and the camera started auto focusing again...this proved to be a VERY temporary fix, however.  I have no idea what's happening nor how to correct the problem...all my previous photography was done with Canon manual focus cameras (F-1, A-1 & T-90) so this is a new problem for me. 

CB in FL

[chrisbroz]

Thanx for the tips...what began as an intermittant problem seems to be becming more frequent; for instance - in darker situation - using flash -  (usually, although sometimes not) when I press the shutter button the shutter doesn't trip...I see the little green bars in the center of the readout come together in the center, fade out...and nothing...not a BUSY notation...nothing.  There is always some kind of light available - I'm not shooting in total darkness...my 65 YO eyes won't allow that...BTW prior to my stroke in '02 at the age of 52 I was a 'serious amateur' (3 35mm bodies - all Canon and a Mamiya RB67) but post stroke lost all interest in just about everything that had at one time been passions - or made me happy...photography being just one.  Now I mostly take shots of out numerous pets. with very little outdoor activity unless it's an airshow or some other  event of that sort..  I also switched from the standard of multi point metering to my preferred 'spot' metering (I used that almost exclusively on my T-90 and forgot to mention that in my original post.)  I'll hafta tyry the one Shot AF and see if that has any effect on the auto focusing problem...I should mention that I leave the settings on "P" since using either aperture or shutter priority doesn't suit my style of shooting I now do.  If I could, I'd get the Tamron 18 - 200 lens (although I understand they've recentkly introduced an 18 - 300 mm variant...that would cover all the situations I'd forsee myself in as I currently don't travel or get around much anymore...I DO however miss the old days of having both an aperture  and prominent focusing ring on the les...again thans to all for their hints/tips...

CB in FL

[TCampbell]

It's normal for the camera to have problems in darker situations.

Some (but not all) flash units have a focus-assist beam.  The Canon 430EX II, for example, will project a beam with a red pattern that the camera can use to lock focus ... even in the dark.  The 320EX has a small LED light that it can turn out for focus assist.  But not all flash units have it.  3rd party units probably will not have the feature.  

[ScottyP]

I almost always shoot in shutter priority mode when it is dim, unless I am using Speedlite flash, when I may use Manual, with or without ETTL.

either of those ways you can set a fast enough shutter to avoid blur from hand shake or from subject motion, and it keeps the camera from lowering the shutter speed to something too slow like 1/20th, etc. Sometimes I forget and leave it in aperture priority and then later on the computer I kick myself when I see a series of important shots that are not sharp.

[ebiggs1]

chrisbroz

I believe you have a faulty camera as I think you sound  like you know your way around the camera.  Have somebody look at it.

BTW, I am nearly 70 and I enjoy shooting more now than ever.   I know we have some "issues" to deal with at this time in our lives but just take it slowly.  You'll be fine and more happy, too.  Photography is great theraphy.

It' kinda fun listening to these young guys as I was there once.

[RobertTheFat]

Understand completely. Surviving a life-threatening illness in middle age can result in a lot of inadvertent attitude adjustment, even if there's little or no long-term brain damage. Been there; done that.

But consider pushing yourself a little; it may help your continuing recovery. Av and Tv aren't that much of a stretch vs P, and they give you a lot more control in certain situations. Also, note that spot metering, if that's actually what you're using, is a much more drastic change than simply switching from multiple AF points to one and can result in fairly major exposure issues if you're not careful.

And if you don't get out much anymore, consider concentrating on what's readily at hand. Maybe get a macro lens and look for what you may have been overlooking in your immediate environment. Pay attention to your dogs and cats, and they may point things out to you. And try to get down to the Senior Center from time to time; perhaps you can network with other photographers who have had to slow down a bit with age or infirmity. Good luck!

[ebiggs1]

Do make some tests outside on a daylight sunny day.  But first re-set the camera to factory defaults and clear all settings first.