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Taking Pictures with Canon DSLRs
Focus Bracketing
![Focus Bracketing : I've been experimenting with focus bracketing. The basic idea is to take one shot, then take 2 more shots with the camera a little closer and a little further away than the first shot without changing the focus setting. The amount the camera needs to be moved depends on depth of field and your confidence in the initial shot's focus.
An easy way to do this is to auto-focus the first shot, then switch to MF for the next 2 shots. Some cameras will allow you to program a button to switch between AF and MF, such as CF4.1 on Canon 5D and lower bodies. Otherwise you can use the AF/MF switch on the lens. I find optimal results with the combination of CF4.1, AI Servo, a large 4GB memory card, partial (or sometimes spot) metering, and continuous-drive mode. On the 5D, AI Servo has 6 extra AF points in the center for motion prediction, and AI Servo (continous focus) is good for most cases where people are moving around a little anyway. Being able to turn off AF using CF4.1 and the "*" button is key. Shooting continuously with a large memory card gives more shots to choose from without having to constantly delete bad shots on the camera.
[The first shot's focus could be done manually if you have the time. This can be made more accurate by (1) pressing down the shutter half way in OneShot mode to get AF feedback while you turn the focus ring, (2) using a Katz Eye split-prism micro-focusing screen ( http://www.keoptics.com), and (3) using an Angle Finder C viewfinder magnifier to see the subject and focusing screen better. If you're shooting without flash and with fast shutter, another option is to shoot in continuous mode and slowly move the camera from one extreme to the other. This is essentially what professional sports photographers do (except that the subject is moving) and why they need cameras like the 1D with a large image buffer.]
The shots below were taken with the 16-35mm f/2.8L zoom at 35mm f/5.6 - not the sharpest lens. My initial MF guess was not very accurate on purpose - I used only AF feedback and turned the focus ring quickly. I have labeled the sharpest image, though it should be obvious. No color correction or sharpening has been performed on any of these, only some exposure compensation.](/photos/random.mg?AlbumID=1231736&Size=Thumb&AlbumKey=pKyDH&rand=7504 "Focus Bracketing : I've been experimenting with focus bracketing. The basic idea is to take one shot, then take 2 more shots with the camera a little closer and a little further away than the first shot without changing the focus setting. The amount the camera needs to be moved depends on depth of field and your confidence in the initial shot's focus.
An easy way to do this is to auto-focus the first shot, then switch to MF for the next 2 shots. Some cameras will allow you to program a button to switch between AF and MF, such as CF4.1 on Canon 5D and lower bodies. Otherwise you can use the AF/MF switch on the lens. I find optimal results with the combination of CF4.1, AI Servo, a large 4GB memory card, partial (or sometimes spot) metering, and continuous-drive mode. On the 5D, AI Servo has 6 extra AF points in the center for motion prediction, and AI Servo (continous focus) is good for most cases where people are moving around a little anyway. Being able to turn off AF using CF4.1 and the \"*\" button is key. Shooting continuously with a large memory card gives more shots to choose from without having to constantly delete bad shots on the camera.
[The first shot's focus could be done manually if you have the time. This can be made more accurate by (1) pressing down the shutter half way in OneShot mode to get AF feedback while you turn the focus ring, (2) using a Katz Eye split-prism micro-focusing screen ( http://www.keoptics.com), and (3) using an Angle Finder C viewfinder magnifier to see the subject and focusing screen better. If you're shooting without flash and with fast shutter, another option is to shoot in continuous mode and slowly move the camera from one extreme to the other. This is essentially what professional sports photographers do (except that the subject is moving) and why they need cameras like the 1D with a large image buffer.]
The shots below were taken with the 16-35mm f/2.8L zoom at 35mm f/5.6 - not the sharpest lens. My initial MF guess was not very accurate on purpose - I used only AF feedback and turned the focus ring quickly. I have labeled the sharpest image, though it should be obvious. No color correction or sharpening has been performed on any of these, only some exposure compensation.")