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Old Oct 5, 2004, 6:15 AM   #1
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When having no specific reason to choose aperture or shutter priority modes I set the dial to Program mode. I am often at wide angle, 28 mm equivalent, (one reason I chose this camera) but find that the chosen values are f/2.8 and a shutter speed to go with it, which may be 1/1000 sec or quicker, whereas I would prefer a smaller aperture for better quality and depth of field. My film SLR camera (also Canon) would not choose this combination!

Also, again in Program mode, the Auto ISO feature does not seem to work, or at least always chooses ISO 50, because it thinks that it will use flash if the scene is not bright enough.

Is anyone else troubled by these problems?
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Old Oct 5, 2004, 11:07 AM   #2
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These "problems" are situation normal for most digitals.

Digicams have a default f-stop (and shutter speed) programmed in, either in the factory or (if you're lucky) there's a menu where you can put in power-on defaults...if you are not happy with the default F-stop and know what you want, you should be using aperture priority mode where you adjust the F-stop and the camera adjusts the shutter speed to compensate for your choice.

In Program mode on many digicams ISO shouldn't be automatic, because it's a mode where you want a little more control than full Auto...with my digicam the difference between Program mode and Auto is you can control the ISO...again check to see if you can change the default power-on settings.

Sorry if these aren't the answers you want, but that's the reality of consumer digicams.
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Old Oct 5, 2004, 11:35 AM   #3
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chuzzlewit wrote:
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When having no specific reason to choose aperture or shutter priority modes I set the dial to Program mode. I am often at wide angle, 28 mm equivalent, (one reason I chose this camera) but find that the chosen values are f/2.8 and a shutter speed to go with it, which may be 1/1000 sec or quicker, whereas I would prefer a smaller aperture for better quality and depth of field. My film SLR camera (also Canon) would not choose this combination!

Also, again in Program mode, the Auto ISO feature does not seem to work, or at least always chooses ISO 50, because it thinks that it will use flash if the scene is not bright enough.
The camera is only trying to give you the best image quality by keeping the aperture set larger and using a lower ISO speed for less noise.

Keep in mind that because the sensor is much smaller on your S60, compared to 35mm film, a much shorter focal length lens can be used to give you the same 35mm equivalent focal length. The actual focal length of the lens on your S60 is only 5.8-20.7mm, to give it a 35mm film equivalent focal length of 28-100mm.

As a result, you'll have dramatically greater depth of field at any given aperture, focus distance and 35mm equivalent focal length compared to your 35mm camera. This is because depth of field is based on the actual (not 35mm equivalent) focal length of the lens.

You'd need to be stopped down to more than f/13 on your 35mm camera, just to match the depth of field you'd get shooting "wide open" at f/2.8 on your S60, for any given 35mm equivalent focal length and focus distance.

Here is a handy online depth of field calculator you can use to compare how this works. Pick a camera model, and make sure to use the actual focal length of the lens for your S60 (5.8 to 20.7mm):

http://www.dofmaster.com/dofjs.html
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Old Oct 7, 2004, 4:40 AM   #4
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I appreciate your time in reading my query and your reply. This morning (UK time) I set the camera on a tripod 'looking' at a static indoor scene.

In Program mode I set ISO to 50 and get a reading 1/20 sec at f/2.8 with camera shake indicated. I set to ISO 200 and get a reading 1/80 sec at f/2.8 (no camera shake indicated). All perfectly normal.

I go to Full Auto mode and set the flash to OFF (which is one of the things I am allowed to do in Full Auto mode) and get a reading 1/20 sec and f/2.8 with camera shake indicated.

I still maintain that Auto Iso Setting is not working - here in Full Auto mode - because the software 'knows' that I have camera shake and should therefore give me a higher ISO rating, e.g. ISO 200.

Hope you can find time to give me any comments.
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Old Oct 7, 2004, 11:20 AM   #5
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Whilst searching Steves Forums, under "Canon>A80 Auto Iso" seems to suggest a similar problem; and there are similar problems from people with Canon A75s.
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Old Oct 7, 2004, 11:44 AM   #6
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chuzzlewit wrote:
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I go to Full Auto mode and set the flash to OFF (which is one of the things I am allowed to do in Full Auto mode) and get a reading 1/20 sec and f/2.8 with camera shake indicated.

I still maintain that Auto Iso Setting is not working - here in Full Auto mode - because the software 'knows' that I have camera shake and should therefore give me a higher ISO rating, e.g. ISO 200.
It's probably basing the camera shake warning on the reciprocal of focal length rule of thumb (1/focal length for hand held photos). But, it has no idea of whether or not you using a tripod.

Since you forced flash off, the designers may have made a decision to keep ISO speeds set lower this way in Auto mode(assuming that most users would be taking longer exposure photos with a tripod if they did force flash off,wanting to keep the noise levels lower).

I've got a little Konica KD-510z (Minolta G500) that has identical behavior (Auto ISO always chooses ISO 50 if you force flash off). It's using the same Sony 1/1.8" 5MP CCD as your Canon uses.

No camera is going to work perfectly for all conditions, and I would have probably designed it to increase ISO speeds, too (to a point). Given the high noise levels from this Sony 5MP 1/1.8" CCD as ISO speeds are increased, I can understand why they would keep it set lower, though.

My little Konica has the ability to setup user profiles with different settings, including ISO speed. So, I just use a different profile for different conditions. I probably keep it set to ISO 100 most of the time (which is a good compromise between noise and shutter speeds in most conditions) -- only increasing it to ISO 200 or more when absolutely necessary.

Once you understand the way your camera behaves, then you can simply use the available modes andsettings to take advantage of it's strengths, and work around it's limitations.
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