Focus when photographing many flowers

First, if this is something I should google/find in a book instead of asking here, please let me know, truly.

Is it always possible or never possible or sometimes possible to get a sharp focus when photographing many flowers? I have a photograph called Pink! that I posted in the High Noon Weekly Challenge that seemed to me to have pretty good focus. Then I have this photograph that I took today, along with others that I've taken over the last couple of days, that I don't seem to be able to get good focus over multiple flowers. Does it have anything to do with the color or type of flower, or should I be able to get good focus over multiple flowers regularly?

Thank you, but, again, please let me know if you think I need to be looking this up myself.

It seems ot be a dof of field issue in this image Barbabra, but without the techs I can't really say

It is your choice of aperture. Try an aperture like f/16 or f/22 or even f/32 (if your lens goes there) for greater depth of field. Of course, that will affect shutter speed so it may cause other problems if you are handholding or if it is a windy day. If what I'm saying doesn't make complete sense, read up on the web (or check out Bryan Peterson's excellent "Understanding Exposure" book) about depth of field/aperture choice. Mike Moats, the Macro forum moderator, also has a good book on macro photography that covers the same topics in a very easy to understand manner.

I agree with Mia, with the elaboration that it might include a point-of-focus issue even if your depth of field at that aperture might otherwise be sufficient. Can't tell about the separation distance for sure, but it looks as though the fence behind the rearmost blossoms is still in focus, even though your front blossoms are not. If you can manage more aperture while also being very critical about the spot you focus on, it should clear right up.

This article and accompanying chart from NPN may help you:

'Demystifying Hyperfocal Focusing for Wide Angle Landscape Photos

Even though the actual numbers don't correspond with your Canon S5, perhaps the points raised will be helpful.

Barbara - Subject distance (focus distance), aperture, and focal length all factor into DOF.

But a couple of questions first : what camera and settings? How close were you to these flowers? And what exactly did you focus on?

I believe you have an S5 IS, and its small sensor, so you should be getting a lot of DOF. (One advantage of a small sensor camera.) And your lens probably goes to f/8 at it's smallest aperture - which you shouldn't even need to go to in order to have most of your scene in focus. For instance, assuming your minimum focal length of 6mm, and a focus at 10 feet away (using the Online DOF Calculator at DOFMaster.com) you get the following :

Aperture.........DOF
f/4.0...............3.72 ft to infinity
f/5.6...............2.92 ft to infinity
f/8.0...............2.28 ft to infinity

As you can see, there will be several feet of DOF in front of the focus point, and lots behind it. Now DOF doesn't mean absolute perfect sharpness, but what appears to be sharp based on certain viewing parameters, so this might not be perfect for your use. But in an example as shown above, if your point of focus is somewhere amongst the first few flowers - AND you're focused more than a few feet away, you should have plenty of DOF.

The issue here might be that you were too close to the flowers - shortening the focus distance. Shorter focus will greatly shrink the DOF, as it looks to me like the front flowers fell outside the DOF (although hard to tell at this size).

Also, I wouldn't use f/8 if possible on your camera, as diffraction effects will show up - shots on my old S2 IS (very similar to yours but with only 5 MP) got some strange patterned bluriness when enlarged/modified shooting at f/8. And you really shouldn't need to anyway.

I agree with everything mentioned above. One other thought that doesn't appear to apply to this image but is often a problem for me when shooting a group of flowers outdoors is subject movement. If there is any breeze at all it can be a big problem, especially when the image requires a larger f-stop and therefor a slower shutter speed. All I can suggest in that situation is going out before the wind picks up, timing your shutter release to lulls in the movement and taking lots of images hoping for some with everything in focus.

I agree with many of the points mentioned above too.
Anyway I'd suggest the following:
-take care of the composition
-be careful with harsh light (it is better to have all the flowers into the shadow)
-put the flowers on the same plane as much as possible
-choose an aperture from f/11 to F/22
-this will reduce the shutter speed, if it is less than 1/125 sec. increase the ISO or use a tripod!
-the use of tripod is always advisable to control the composition of the image and its sharpness!
For reference see my photos (in particular the last one I posted to-day on the flora gallery)
Greetings.
Mauro

Thanks very much, everyone. David, you're correct in that my smallest aperture setting is f/8. If I install the CHDK, I think that will add some. I believe you're also correct in that I was too close to the flowers. That didn't even occur to me. (I need a slapping oneself in the forehead smiley). I tried again today but couldn't get a good position from further away. John, thank you so much for the link. Thanks to everyone else, too.

Barbara - It's doubtful that you can get an aperture smaller than f/8. That's probably the smallest the aperture blades are mechanically designed to go - so they may not physically go further. Things like shutter speed limits could be, because that's not a mechanical limitation. But for the shutter opening, It's probably not controlled by a firmware setting.

At 6mm (full wide angle) the opening in the aperture at f/8 will only be about 0.75 mm - really tiny already.