S30/40 autofocus nightmare

[marcstck]

I'm a (at this point) disgruntled owner of an S30. From the start, I've found the camera to be plagued with inconsistent focusing. I've sent the camera in for service, where they finally replaced the unit (after I sent the camera back a second time), but to no avail. The thing just won't consistently maintain sharp focus.

I'm an experienced photographer who holds the camera steady, so camera shake is not a factor. I've found that you can check the focus distance by hitting the manual focus button after the autofocus has found its mark (green box), as long as you maintain a half press on the shutter release. This reveals that, when pointed at the same object multiple times, the focus distance changes with each attempt at autofocus. In other words, the
camera will choose three different focal points in three attempts at framing the same composition (using the same shutter speed and aperature). My only conclusion is that the S30/40 autofocus system is defective.

After reading a few message boards, I've come to realize that this is a common, known problem. Why doesn't Canon address this with a firmware update, or recall the camera for replacement by a unit the actually works!?

Comments?

[octathlon]

Even worse is trying to use the MANUAL focus, for anything but infinity.

One thing that will help a lot is to select an individual AF (AutoFocus) frame by pressing the center button of the multicontroller. Then use left/right to select left, middle, or right AF frame (I always use the middle one and reframe after focusing). You can't do this in auto mode.

If you don't select it yourself, the camera will use all 3 frames and decide focus based on some algorithm. Good luck.

[pblevitt]

Found a few tips http://www.photocourse.com/04/04-04.htm

[tovli]

I'm wouldn't call my experience with an S40 a nightmare, but I've certainly been spending a lot of nights trying to get just one picture from my camera that impresses the wife!

Here's what I've learned...

I get my best outdoor pics in Aperature mode with the lens stopped down midway ~f5.6, adding fill flash on people in shade or clouds, selecting cloudy white balance when cloudy, only center focus and often adding +1/3 exposure.

I get my best indoor flash pics with +1 flash power.

I'm still playing with setting +sharp or +contrast in the camera, in search of a crisp feeling. Even though the reviews of the S40 show good resolution, all my "auto" pictures seem pretty dead. I did a side by side picture with a Nikon 4500 of a tree outdoors. The Nikon picture was clearly sharper.

I wanted a small camera with good pictures for snapshots. First I tried the Minolta F100 - pics too red, traded for the Canon S40 - colors look ok, perhaps a bit undersaturated or slightly low contrast (supposedly would get the most info to the file).

Keep us posted on your findings.

[PaulS45]

I've had an S45 for one week and have exactly the same experience of lack of sharp focus on both indoor and cloudy outdoor shots. My old 3 year old Sony digicam seems to produce sharper pictures. Still playing around with different settings so the advice here is valuable.

Paul

[tovli]

I have finished profiling my Epson 870 printer and my Canon S40, and find that with these color profiles in QImage, with a global filter of radius 1 @ 100% unsharp masking, my prints are now what I expected from my 4 megapixel camera.

Now I get great color saturation, razor sharpness without artifacts, and contrast that makes the pictures look like an open window, instead of the foggy, blurry, and dark "photographs" I was trying to impress my wife with before.

[Plugin]

I am concidering getting an S40, should I re-think my decision given this problem? Couldnt it be a firmware issue?

[steelcase]

I have the same problem with my S30. The camera is very sensitive, holding it makes everything out of focus. I have to put the camera on a furniture for a sharp picture. :(

I don't think everyone have this problem after reading the feedback on Cnet (http://electronics.cnet.com/electronics/0-6613935-1318-7738969.html?tag=st.ce.6613935-1304-7738969.box.6613935-1318-7738969). Should I have my camera replaced?

[tovli]

steelcase wrote:
have to put the camera on a furniture for a sharp picture. :(

Should I have my camera replaced?

Sounds to me like you need more light in the room. Before you try replacing the camera, bring some extra lights into the room and try your shots again. You may be surprised at the difference.

BTW, since the auto setting tries to maximize the light by keeping the lens wide open, you might want to try the Av setting and bump the aperature some. Again, this takes more light than most homes have inside!

Lastly, using a basic unsharp mask on each picture has become a part of my workflow. It really makes a pleasant difference.

[John Blake]

Please explain to a novice what an unsharp mask is? Sounds as though I need one, as I have an S40, and would like to improve my pictures.

[tovli]

John Blake wrote:
Please explain to a novice what an unsharp mask is?

There are several types of sharpening "effects" you can use on your pictures:

1: In Camera sharpening - I don't know what algorithm this uses. It is either (- 0 +), so you can decrease, leave as "normal" or increase the sharpness recorded to the jpg file. Setting this to + seems to me to do an "edge highlight effect" which is not as good as unsharp masking.

2: Post Camera Sharpening - There are two major algorithms here:

2a: Post Camera edge highlight - this is what most simple printing and album programs, (and your television), use if they have a sharpen slider. This will put increasingly bright white line next to the left side of every edge in the picture. This "fools" the eye into thinking the picture is sharp, but it completely removes color and detail info under the affected edges.

2b: Post Camera unsharp masking - this is available in the better editing and printing packages such as Adobe PhotoShop LE, and QImage to name just one editor and one printing program. This algorithm is adjustable for radius and percentage. For radius I usually try 1,2 or 3 and percentage I start at 100%.

Unsharp masking is the prefered technique. I use a global unsharp mask of 100%, radius 2 to print proof 4x6s from a session.