Is My Auto Focus Broken?

I have a 50D, I wanted to use the Dot Tune method to set micro adjust focus. https://photography-on-the.net …48&highlight=Fo​CAl+reiken

I look through the view finder and see the the center focus spot quickly blink red when I push the shutter button half way.

There is a round green focus confirmation light at the lower right of the viewfinder but it never comes or or even flickers.

I also turned on the beeper which I would expect to make a beep sound when focus is confirmed.

I tried with two different lenses, auto ISO and 100 ISO, F2.8 and still no beep no focus confirmation light in the viewfinder. I tried a well lit kitchen, and out doors on a bright moring. Still no beep no green light.

Am I doing something wrong or is there a problem with the camera body?

Any ideas?

Thanks

tekin112000 wrote in post #17155442
I have a 50D, I wanted to use the Dot Tune method to set micro adjust focus. https://photography-on-the.net …48&highlight=Fo​CAl+reiken

I look through the view finder and see the the center focus spot quickly blink red when I push the shutter button half way.

There is a round green focus confirmation light at the lower right of the viewfinder but it never comes or or even flickers.

I also turned on the beeper which I would expect to make a beep sound when focus is confirmed.

I tried with two different lenses, auto ISO and 100 ISO, F2.8 and still no beep no focus confirmation light in the viewfinder. I tried a well lit kitchen, and out doors on a bright moring. Still no beep no green light.

Am I doing something wrong or is there a problem with the camera body?

Any ideas?

Thanks

Do you have the *lenses* set to the AF position?

Yes set to AF

I have pointed the camera at near subjects, push halfway on the shutter, center focus point blinks red. Then I point at a subject at a different distance, I again push halfway on the shutter, I hear the lens motor readjust, see the focus point blink red

Maybe One shot autofocus instead of servo?

Anything here of help? Make sure you scroll down as there are big breaks in the page often making you think you are at the end.

http://www.canon-europe.com …faqdetailid=tcm​:13-782570

You are probably in AI servo mode- it will never beep or light up when focus is confirmed, it is always trying to achieve focus. See the middle of page 85.


http://gdlp01.c-wss.com …01591/02/eos50d​-h2-en.pdf

Yep, chances are that you have the wrong focus mode selected....

One Shot is for stationary subjects... Once it acquires focus it stops and locks, you get Focus Confirmation (green LED lights up and, if you have it enabled, you get the audible "beep"). If either your or your subject moves (or if you change the focal length of many modern zooms), in order to re-focus you must release the button and then reapply pressure to make the camera re-acquire focus.

AI Servo is for moving subjects... It acquires focus, but then continuously updates focus as long as you hold the shutter button half-pressed (or back button pressed, if using back button focusing technique), in order to track with the moving subject. In AI Servo focus never locks and you don't get Focus Confirmation (there's nothing to confirm, since AF is still running). AI Servo is ideal if using a zoom that's varifocal design (doesn't maintain focus when zoomed to change the focal length)... AI Servo will keep the lens focused.

AI Focus isn't really a focus mode at all... It's an automated mode that's supposed to decide for you whether or not the subject is moving, then switch to use the correct mode: AI Servo or One Shot. In my experience, it results in a short delay and doesn't always choose correctly... So I never use it. It might be a hint, that Canon's most pro-oriented cameras only have two modes: AI Servo and One Shot. They don't have AI Focus at all.

I can't recall the last time I used AI Focus on any of my Canon DSLRs. I use Back Button Focus, which allows me to use AI Servo by default. I switch to One Shot in certain situations, such as when I want a high degree of precision or am using a hyperfocal focusing distance method of focusing.

Thank you All.

I set focus to One Shot and got a beep and a green confirmation light.