Canon 40 d Wont Shoot if Not Focused?

zoiberg137 · Feb 15, 2012

So I'm aware that the 40d is know for having shutter problems, where the shutter "freezes" up intermittently. I don't think that's the problem I'm having, though.

My camera seems to work fine, until I try to take a picture of something close up, like a flower or insect. The camera tries to focus, but cant unless I back up a little. But it refuses to take a picture until it completely focuses. This is SO frustrating! I want the camera to take a picture every time I hit the button, REGARDLESS of whether it thinks its focused or not.

I'm starting to wonder if the only way I can take close up shots is with a macro lens. Or maybe a cheap close up lens?? Would that allow it to focus?

What I would really like to do is to go into the settings and tell it to take a picture whenever the button is pushed, no matter what the conditions are. IS there a setting for this?? I am sincerely hoping that there is...

I am shooting in Program mode by the way.

Thanks!

bazooka · Feb 15, 2012

You can disable this "safety" in the menu. By default it won't allow you to shoot if there isn't focus confirmation.

Rephargotohp · Feb 15, 2012

If you are shooting in "One Shot" Focus mode, The camera will not allow the shutter to fire unless focus lock is obtained.

You could of course switch to manual focus and the camera will fire regardless of "Lock"

Or if you want to maintain using AF/ switching to AI Servo focus mode,(Press AF-WB button, turn finger wheel) will also fire regardless of if Focus lock is obtained. But it is a continuous focus mode so if you recompose the focus will move to the object under the focus point.

So that solves that but does it really solve your problem, since now you will be able to shoot even if your subject is NOT in focus. The problem is you are trying to shoot closer than your minimum focus distance of your lens. So you either need a lens with a shorter minimum focus distance ( which could be a Macro lens) or you can use extension tubes with your current lens that allow for a shorter focus distance

Overread · Feb 15, 2012

Set the lens to manual focusing mode and you can take shots whenever you want. If you're shooting macro and close up work this is actually the normal way most people shoot it because close distances can tend to confuse/cause problems with most AF systems.

Just set your lenses focusing to the closest possible focusing point and then move the camera closer and further away from the subject to put the focus where you want it. Of course this is a limit as to how "close" you can get and thereafter the lens will be out of focus.

If you want to go past that limit you've a few options:

1) Extension tubes - these reduce the minimum focusing distance and let you focus closer and thus get a higher magnification shot of small subjects. They also remove infinity focus so you'll be limited to maybe only a few inches or feet of focusing.
A good set like a Kenko AF set is an ideal option and one of the best ways when your on budget with a shorter focal length lens. Note that you need a good set (like the Kenko) because you need the metal communication contacts so that you can control the lenses aperture (there is a trick to change aperture on canon lenses, but its limited in forcing you to focus and shoot with the aperture always closed down).

2) Close up lens attachments - avoid the cheap ones, they work but are single element and generally so cheap that they'll degrade lens performance significantly. A good series are the Raynox - the DCR 150 and DCR 250 are very popular and not that expensive. They are better (ie give more magnification) on longer lenses, so if you've only a typical kit lens under 100mm the extension tubes would be superior.
They work like extension tubes, reducing minimum focusing distances and also removing infinity focusing.

3) Get a dedicated macro lens - these have the advantages that they are able to shoot macro and retain infinity focus without the need to be adding or removing components. They will also have a greater working distance (distance between the front of the lens and the subject) which can make shooting a lot easier since you are not pressed right up to the subject and thus casting a big shadow over it.

ph0enix · Feb 15, 2012

Minimum focusing distance is a property of the lens. Every lens has one. If you want to know what it is for yours, just look at its specs. As others have suggested, simply switch to manual focus if you need to take a photo at a closer range.