The specifications for the S400 show:
Focus range
Normal - 1.5 feet to infinity
Macro (wide) 2.0 to 18.1 inches
Macro (Tele) 11.8 to 18.1 inches
I was having trouble getting a good focus on one camera and decided to try in a controlled invironment.
I discovered the problem.
Get outside in a shady location on a sunny day.
A covered porch is nice.
Set up a table and select a small target (a tiny toy car is good).
Switch to macro mode (do not use zoom) and position the lens about 6 inches from the target. View the target with the LCD and watch as the focus changes as you move a few inches further and closer.
I wasn't having much luck, so I put the camera on a tripod and tried again. Then I could see the camera focus on the target.
It seems to take longer for the camera to focus when using macro mode. If you are hand holding the camera, the focus mechanism is continuously searching due to camera movement.
Try with a tripod, or set the camera on something solid. Or hand hold the camera rock steady - which I can't do consistantly.
Anyway you now know why this is called table-top photography. Now that you have your table-top studio set up, practice on every small object you can find.
You will soon see the very shallow depth of field when shooting macro. i.e. if you focus on one part of the toy car, the part of the car that is further from the lens will be out of focus. This is normal and as you add more light the depth of field gets bigger. If you want a shallow depth of field, decrease the amount of light.
Lighting plays a big part in table-top photography.
There is a S400 macho photo shown on this page:
http://www.dpreview.com/reviews/canons400/page11.asp
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When ever I switch to a macro setting to get a really good close-up of a flower, it seems that the image is really out-of-focus all the time.
I use a Canon Sure-Shot S-400 Digital Elph.
Some times I have better results using the regular zoom feature in place of the macro setting. Any settings for the macro that I should be aware of?
What am I doing wrong?
Thanks.

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