EOS SL1 auto focus doesn't work. Seems to happen on hot days

[Bankesmom1]

My Rebel SL1 with a Tamron telephoto lens won't auto focus on warm days.  It will sometimes work at close focus, but when zooming in, it won't auto focus. Does anyone have an answer to this.  Same thing happened last year, but my local camera shop could give me no answers.  It was the shop where I purchased the camera, and I was disappointed with their response.  The weather has warmed up, I wanted to take pictures at a grandson's baseball game and no autofocus.  Frustrating.

[Bankesmom1]

I don't have issues with the lens auto focusing at close distances.  Only at far.  For instance, I can auto focus on a batter in the on deck circle, but not at the plate, or anything beyond, ie infield or outfield.  When I first start out taking pictures, things are good, but then after a while the auto focus stops working.  Thanks for your questions and maybe being able to help me out.

[Bankesmom1]

It's the 18-270 mm F/3.5-6.3.  Some times if I turn off the camera and turn it back on it might work, but after a few tries, even that stops working so I have to go to manual focus.  That doesn't work if I'm taking shots in sports mode to catch the action.  Thanks for your question and maybe being able to help me out.

[Bankesmom1]

Thanks for the philosophy lesson, but yes, I have tried this lens in both hot, cold and warm.  Baseball, football, and basketball.  Hence the different temperatures and my deduction that possibly the hot temperature could be the variable that makes this happen.

I do use a Canon battery, the one that came with the camera.  I, too, have wondered if it might be the battery. Would you suggest buying a new battery then? In some of the reading I've done, I've seen some comments are the settings for exposures.  All good points, and thank you so much for your assistance. 

[Bankesmom1]

No.  I take pictures at basketball games, and football games too.  And it's never been an issue in those circumstances.  Any other ideas for me?  Thanks for the input.

[Bankesmom1]

Ouch

[deebatman316]

What are the lighting conditions like when this happens. If its dark and lacks contrast the camera will struggle to lock focus. What mode are you shooting in on the top mode dial. Are you shooting in A+/ Green Square Mode. Your camera has 2 main focus modes there's also a 3rd. Your main focus modes are One Shot and AI Servo. One Shot is focus priority. The camera won't take a picture unless its in focus. AI Servo is release priority. The camera will take pictures regardless if the pictures are in focus or not. The 3rd is AI Focus its a hybrid mode. The camera will start out in One Shot then switches to AI Servo if it detects subject movement. This mode IS NOT recommended because camera shake can cause the camera to switch to AI Servo. The lens has a variable aperture F/3.5-6.3 which is slow. At 18mm F/3.5 is wide open. But at 270mm F/6.3 is wide open. The bigger the number the less light enters the camera. Also please post some pictures in the forum too. So forum members can better assist you.

[Bankesmom1]

The lighting conditions are always good.  Outdoor baseball games either daylight, or lighted fields, football the same, and basketball in gymnasiums.  Basketball pictures aren't nearly as good, I need to invest in a different lens because of the low light situations in there.  And I shoot in sports mode to catch the action, and I believe that in sports mode, the default setting is continuous shooting.

[Bankesmom1]

Thanks so much!!!!

[deebatman316]

I would suggest learning about the exposure triangle. Then discontinue the use of Sports Mode or any other Fully Automated shooting mode. Your camera uses an older AF system. Your camera has 7 AF Points. So the sensitivity of the AF system will have limits. All camera gear has limits.

[Bankesmom1]