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View Full Version : Focal Points - what am I doing wrong???



ccrnkovic
29-07-2010, 8:13pm
Well, I am getting to know my 450D and just realized that I have not been using the 9 focal points correctly, DOH. I am always wondering why some of my shots are fantastic, while others are really bad!!

My questions is at the moment I am shooting in Auto and when I press the shutter down half way the focal points light up - they do not always light up - eg. I am taking a photograph of a person where do I put these focal points? are these the points that go on the eyes???

sorry if this sounds a weird question, it is hard to explain.

Thanks

Riverlander
29-07-2010, 8:21pm
If you have all the points turned on, then the camera will focus using whichever point/s is/are "covering" the object/s nearest to you. Simple as that.

dche5390
29-07-2010, 8:23pm
The centre AF point is the most efficient and reliable. Especially with Canons. You can let the camera decide everything else but point of focus.

Let us know if you need help taking control of the AF point.

ccrnkovic
29-07-2010, 9:57pm
Thank you, help with the AF point would be great!

rwg717
29-07-2010, 10:06pm
I have a 450D but have loaned it out so can't tell you how to go about changing the focus point right now. I know that it is easily changed by pressing the button (magnifier) at the top right on the back of the camera and then looking through the viewfinder select the available points by rolling the dial near the shutter button with your right index finger, press "set" and you're done.

As a matter of course all my Canon bodies are set this way, the general rule for shooting people is to aim at their eye, press the shutter button half way, hold it there and move the camera so as to re-compose the subject in the frame and press the button all the way, job done:D
Richard

bigdazzler
30-07-2010, 12:38am
I use centre spot AF, focus lock and recompose method. That way I choose where to focus, the camera has no say.

rwg717
30-07-2010, 9:55pm
I use centre spot AF, focus lock and recompose method. That way I choose where to focus, the camera has no say.

Yes, the ideal way to do it, I was trying to avoid any complications, these are shortcuts which you and I use through experience, just thought I would keep it simple for now:D
Richard

Mat
30-07-2010, 10:04pm
I also focus in the center and then recompose... perhaps a hang up from the 35mm SLR but it works.

bigdazzler
31-07-2010, 9:26am
It does work ... unless.... the distance from your lens to the subject changes, then you lose your lock and have to start again.

vk2gwk
03-08-2010, 10:42am
Most of the time I use only one - usually the central - focussing point on my (Canon) camera. As suggested earlier you can focus and then recompose. But... beware! When recomposing - even with a static subject - you may lose focus because the depth of field is more or less circular. When recomposing the distance from the lens to the subjects changes and it may move out of the depth of field - especially when using a wide aperture (like F/5.6 and wider). In that sort of situations it can be useful to choose another - more periferal focussing point. At least with Canon the problem is that the periferal focussing points are not as sensitive in low light situations as the central on.

With moving subjects like children, animals or vehicles use AI-servo and not One Shot.

Get away from the A-setting. Choose P or one of the priority setting (Av or Tv) where approriate and when you gain experience go to M to optimise aperture, shutterspeed and ISO setting for each shot.
Keep shooting!

reaction
03-08-2010, 2:06pm
always set manual AF points. recompose or not you can't rely on auto AF points, especially with the xxxD line.

ving
03-08-2010, 2:08pm
i choose my own FP :D

Fantasyphoto
03-08-2010, 2:44pm
I too manually select my own focus point, it usually leaves less room for error when/if you need to recompose.

tanz
03-08-2010, 4:34pm
Keeping in mind that you mentioned in your first post that are still shooting in auto and in that case you can not manually select your focus point (I can't on my 550 so I guess the 450 would be the same). If you switch your camera to Av or Tv mode to have a play then you will be able to select your focus point

David
03-08-2010, 4:55pm
I have a 450D but have loaned it out so can't tell you how to go about changing the focus point right now. I know that it is easily changed by pressing the button (magnifier) at the top right on the back of the camera and then looking through the viewfinder select the available points by rolling the dial near the shutter button with your right index finger, press "set" and you're done.

As a matter of course all my Canon bodies are set this way, the general rule for shooting people is to aim at their eye, press the shutter button half way, hold it there and move the camera so as to re-compose the subject in the frame and press the button all the way, job done:D
Richard

Spot on Richard. The only thing is you have to use M or TV or AV to get control over the focus point. Use ONE point (the centre one), aim that at your main subject, half click the shutter, recompose the shot then hit the shutter all the way down, bang focused shot.

BUT there is also the depth of feild issue so make sure you have an Apeture setting that will cover the distance between camera and subject well. If you set the Apeture at 4.0 for example the risk is any movement will blur your image (and people will move on you).

At at the same time, don't set the Apeture at F11 (for example) or higher (16/22) for your portrait shots because each stop of Apeture speed you ask for from the camera to ensure depth of field will cost you a stop in shutter speed and therein increase the risk of movement blur from either the subject or the camera when you take the shot.

Learn how to pick a focus point in AV TV or Manual mode and you control the focus so long as the Depth of Field (Apeture setting) is adequate to give a reasonably sharp rendition of the rest of the subject matter inside the frame apart from your main subject.

PS: What you pick as you focus point will change according to the subject matter inside the frame; For landscapes I pick a focus point one third up from the bottom of the frame to ensure front to back depth of field and a higher apeture (f11 f 16 f22) but for Portraits I would be working down the other end (4.0, 5.6, 7.1, 8.0) of the Apeture scale and aiming my focus point at the eyes of the subject, keeping in mind the wider you go (4.0 for example), the more spot on your focus point has to be or you ended up with a blur.

tanz
03-08-2010, 5:20pm
Just another thought - I don't know what program you use to view your images but if you use zoom browser, which is one of the programs on the disc that came with your camera, then you can select one of the buttons up the top and this will show you on each photo all the focus points and the ones that were used are in red. :umm: unless you have recomposed the shot and then the red ones are going to be over to the left or right of the subject. This way you can look back on each photo and see why some didn't turn out as good as you were expecting. I am sure other programs can do this as well but I am also new to photography and don't really know much about all the programs.

elyshiamadison
19-09-2010, 3:20pm
Got to agree, don't let the camera "randomly pick" one of the focus points.... I have seen too many shots that you can bet the quickest point to lock was behind the intended focal point!

I use the centre point - and recompose and shoot (with moving objects I turn on AI servo, and it seems to still keep the same focus even after I have recomposed off centre)

mareech
08-10-2010, 8:37pm
Hi thanks for this info, I am inexperienced with my 400d and have been having focus trouble trying to capture birds where there are branches etc nearby. The autofocus is going flat out and when I capture it is not always clear. I even resorted to manual focus. I was wondering how you got it to focus on the eye only, I will be giving this a go tomorrow. Thanks

Sobriquet
07-11-2010, 9:09pm
I tend to not use the centre one, set it to one of the focus points closer to a rule of thirds line (on the far left or right). I change it often to suit the situation. On my cameras (not 450D sorry) it is a button near my thumb on the top right of the back to the camera, check your manual and practise changing it without looking. Good luck

Edited to say you want One Shot focus noy Ai Servo (for moving targets) if you want to control more closely where you focus

wanderer51
07-11-2010, 10:46pm
On my 400D, I usually use the centre focus point, except, as David has said a few posts up, for Landscapes.
The 450D has the same setup as the 400D to select which focal point you want. It should be the button at the top right...the one with the magnifying glass with the + sign in it. Above that button on the camera top is a little square with some dots arranged in a cross pattern. Once you press that button the LCD will show you the focus points. Pressing the 'SET' button toggles between Auto select and manual select. In the case of manual select, pressing the curved buttons surrounding 'SET' will move the active focus point.
Hope that all makes sense!

LJG
08-11-2010, 8:28am
My questions is at the moment I am shooting in Auto and when I press the shutter down half way the focal points light up - they do not always light up - eg. I am taking a photograph of a person where do I put these focal points? are these the points that go on the eyes???



If you are shooting in full Auto the camera will choose the settings, I think including focus points on the 450. My son has mine ATM so I can't check, but I'm pretty sure you need to switch over to a manual setting to be able to choose the focus point. As already mentioned the centre point is the most sensitive.

philiph
24-11-2010, 5:03pm
I use the centre focal point for shooting birds as so that I know exactly what will be in focus. The other thing to look at is the AI Focus and AI Servo (or similar) setting on the camera. The servo setting is recommended for moving objects as the camera will re-focus as you track the subject. The manual explains it better than I can but it will take a bit of getting used to and depends on what you are shooting, which is why they invented digital cameras- so you can take lots of practice shots. Good luck and keep shooting

Jcas
25-11-2010, 4:05pm
This has been an informative thread for me , thanks to all contributors .. :)

silkdiver
26-11-2010, 8:32am
Also very informative for me, ty all.