Beginner Focus Points - Canon 450d/50mm 1.4

[Bolly]

Hi all

I am still trying to get to grips with the basics, but I am struggling with something which might be down to beginner/user error.

I am using a canon 450d paired with a 50mm 1.4. When it goes well, the pics are lovely, but sometimes I feel that it is 'click & hope' and I don't get the pic I was hoping for. I want more control.

Now, I understand that the 450 is an entry body (and now an old model), but there is about 8 or 9 focal points. I tend to have the camera in AV mode 98% of the time, but why is it that sometime one focal point engages and at other times the camera focuses on two or three or more points.

I sometimes get nice pics, but only one point is in focus. Everything else is blurry. I want to take more portraits of my wife holding my son, but I can't get both in focus. It is driving me nuts and I am using the camera phone more than I want to.

Is it because I am using a prime lens? Is it because the body is old? Do I need to learn to use the body better and if so, what should I be reading?

Many thanks

 

[seriousrikk]

I think it could be for a couple of reasons.

Lets address what you want to achieve - and that is get your wife and baby in focus. You need to set your aperture appropriately to do this, since you are in AV mode you are controlling this. What are you setting your aperture to? At F1.4 you depth of field will be very thin, indeed at F2.8 it's going to be pretty narrow and probably not enough to get both in focus.

Have a play here to see what aperture you need to achieve what you want. http://www.dofmaster.com/dofjs.html

Now, focus points. It sounds like you have the camera on the default setting of all focus points active. I don't know how, but the manual should give details on how to select just a single focus point for your camera. This will default to the center point usually, but then you can choose the focus point you wish to use. I know on the xxD models there is a button on the rear for focus point selection going back a number of years, but I never had one do the xxxD cameras.

Then, armed with the knowledge about the appropriate aperture, select what you wish to focus on and you should be fine. The biggest risk is by having an appropriate aperture you are not letting as much light in and your shutter speed will drop. Cross that bridge when you come to it!

 

[Phil V]

Your camera has some fantastic automatic features, but the one 'auto' mode that's completely stupid is the 'auto focus point select'.

Before you learn any other photographic technique, take control of what your subject is, that requires you taking control of the focus point selection.

Following that, with more than one area of interest, you'll need to learn about depth of field (the distance between the objects you'd like to have acceptably sharp).

 

[StewartR]

I tend to have the camera in AV mode 98% of the time, but why is it that sometime one focal point engages and at other times the camera focuses on two or three or more points. ... Do I need to learn to use the body better and if so, what should I be reading?

Yes you do, and the first thing you should be reading is your camera manual. Page 61 in particular:

If you didn't get a printed copy of the manual with your camera, you can download it here:
http://files.canon-europe.com/files/soft31340/manual/CUG_EOS450D_EN_Flat.pdf