One thing I notice is that often, even working photographers get focus wrong. So let me go back to basics with you today. Focus basics.
There are two focus “settings”: where to focus and how to focus. Today, where to focus.
In the basic “auto” modes, you let the camera choose. You see all focus areas (all three, or all 9, or all 11, or all 42 – depends on your camera) and when you press the shutter halfway, the camera indicates which ones it uses.
These are the ones that have a close object. So you would get this:
But is that clever? Surely you should choose? Perhaps you want this, instead?
That can only be done if you:
- Select one focus point (read your camera manual if you need help doing that)
- Aim that focus point at the subject you want to have sharp
- Press half way down (you will hear a beep, if you haven’t disabled the beep)
- While holding the button half way down, recompose, if you like
- Press the shutter all the way down to take the image.
This is how you shoot most of the time. Letting the camera choose where to focus is not a great idea. It does not have a brain, and even if it did, it wouldn’t be your brain. And no, “more focus points” does not mean “greater depth of field, i.e. more focus”! It merely means “camera gets to choose”.
So go set your camera to one focus point pronto!
Some shots can be a little tricky. Like this one, from Sunday’s shoot:
Tricky why? Because the model is jumping, making it hard to focus.
The solution? You could try AF-C/AI-Servo, i.e. continuous focus. But often in these cases a better solution is this (and that is what I did): pre-focus, then hold that focus while he jumps. So I had the model stand where he would be when I take the shot; then focused there and held that focus while he moved back and jumped; then I shot when he was once again in the same place.
Why is he not blurry? Because he is substantially lit by the flash, which fires faster than 1/1000th second.
Another, different challenge was presented by this shot:
Why? Because the original plan was to light the aquarium in part from behind. But I was shooting TTL, and guess what? I found out on Sunday that the light-driven TTL does not work through an aquarium. Fancy that. You learn something new every day, even when you have been doing it forever.
The solution was to light it from the sides instead, after removing the aquarium side doors. Sometimes you just have to change your plans a little bit!
Enjoy your speedlighting, everyone. I am off to sleep – finally, at 3AM.
I get the following question rather lot – so when another reader asked a few days ago, I thought “let’s answer for everyone”.
When shooting, I usually use the center focus point (Canon 40D) to select what I want to focus on, press halfway and then recompose. I have recently gone through some pictures I have taken with Aperture 3, and have clicked “show focus points” and it shows that my focus point was off. It appears as though my camera did not lock the focus. I have done some research on different forums to find out what the problem could be, and some people discussed the modes “AI Servo, AI Focus, One Shot”… Should this affect the focus lock? Would I be better off changing which of the 9 focus points I wish to use for each shot rather than locking and recomposing? (I would rather not since it’s more time consuming!)
You are fine. You are using “one shot”, or you would not see a focus point displayed. You see, the “display focus point” function is only useful if you do not recompose, since the computer doesn’t know you recomposed. So the computer shows which point you used, but not where it was when you shot.
I.e. There’s no problems. The image is sharp where you wanted, right?
Your other question: yes, although the centre point is more sensitive, and is sensitive to both vertical and horizontal lines, it is usually more accurate to move the focus point. You can make this easier on many cameras by custom functions. But unless you are shooting with very narrow depth of field, you can usually get away with using the centre point and recomposing.
Today, I helped a student get to grips with shooting with a long lens.
So….was it really all that long? 70-200mm. And 200mm is not actually long when you are shooting small birds, some 10m away:
This was shot at 1600 ISO – it was a dull cloudy day and with birds you want high speed, which means high ISO even when you have a good lens opened up to f/2.8.
So the lens is short. So we have to crop. And when you crop, you see the limitations (click to see this part of the image at full size):
So.. what are some strategies you can use to get sharp pictures?
First, do not shoot through obstructions. Through a clean window pane, and with a filter on the lens, we got this (a small crop out of the image):
Without the filter and window, this becomes:
- Use a good quality lens. Lenses are not what you should be saving on!
- Shoot at a fast enough shutter speed. “1 / lens length” or much better. I prefer to do this by using aperture mode at aperture wide (or nearly wide) open.
- Now set the ISO high enough to get a good shutter speed.
- Use VR/IS stabilization.
- Consider using a monopod (or even a tripod): one with a quick release.
- Focus on the background, then focus on the bird, then shoot.
- Use One Shot/AF-S focus, unless the subject moves. In that case use AI Servo/AF-C.
- Focus on contrasty bits!
- Use one focus spot, and avoid mis-focusing.
- Light well, if you can – meaning “light bright and expose to the right”. My dictum: “Bright pixels are sharp pixels”.
- Take multiple images and use what works. Your lens will mis-focus occasionally.
Also, consider stopping down the aperture a bit when you have to. Like when the bird is inside a tree… f/2.8 gives you this:
While f/4 gives you this:
That depth of field is much better.
And one more, where a bird is “bright pixels”:
Concluding, there is not one way to get sharp pictures. The best technique is to try to stack the odds in your favour by using as many of the techniques described above.