It is now a very loose term. Generally the following things will get dragged in to any discussion that starts with the term fog-effect and the S2
(can't comment on the S3):
- The reviews reported the S2 images as "slightly soft" - ie not as sharp - some say this is because Canon tends not to overprocess an image which allows you to better work with this later (its hard to reverse an oversharpened image). Some say its just a bad camera. Look at sample review full-sized images and judge for yourself.
- Some people try to take high zoom photos when there isn't enough light - which causes images that look out of focus due to camera-shake and subject-movement. People often post asking if this is the fog-effect. A very overcast day, or daytime shade can be too dark for maximum-zoom if the subject is moving - you can't get the shutter speed high enough on low-ISO - high-ISO is too noisy - so you might have to use less zoom on dull days. This implies the camera is not so good for indoor sports.
- Some people try to max-zoom through kilometres of smog/fog/mist which cause images to look out of focus or lack sharpness.[/*]
- Some people don't like the rather neutral images, preferring to boost the contrast, or use the camera in Vivid mode (which also boosts the contrast). You can tweak many settings - some want more neutral images - some want less.
- Some people think the autofocus is too-slow or not-accurate. For example, the H1 is faster to focus (but the S2 has a higher maximum continuous shot-mode).
- Some think the camera should take perfect pictures on auto more often. Most people advise that full-auto won't cut it and some learning is necessary. The auto is probably less effective than non-superzooms because the camera is more extreme in its range of capabilities. From looking in several forums, it seems to me all first time superzoom users go through a learning curve.
- Some think there is too much purple-fringing and colour aberration. But the amount seen is similar to other superzooms (but more than some non superzooms - eg Canon Pro1). (If a scene has black/white contrast - stay around f/5.2 to minimise this.)
- Some think the lower dynamic range (brightest to darkest pixel) in the higher megapixel cameras is unacceptably worse than the old lower megapixel cameras.[/*]
- Some think the amount of noise in the shadows is unacceptably worse than older lower megapixel cameras.
- Some think that too many images need post-processing - eg needing something like google's picassa to sharpen an image.[/*]
- Some people have posted reduced sized images without using an unsharp-mask as a final step - this causes the images to look "soft" - down size resampling looses detail - USM puts the illusion of detail back - any S2 image like this will be immediately attacked as having the fog-effect.
Have I forgotten any?
But many people are quite happy with there S2's. I'm certainly happy with mine and have had a lot of fun with it. You definitely have to learn how to use it, and I'd say you'd want to look into using something like Picassa to help tweak the final images. You can see my samples at http://www.flickr.com/photos/[email protected]/
( I quite often add notes on what post-processing was necessary. Warning - most of my sample bird images were taken at under 4 metres - don't think you can take images like that from longer distances - small birds are just too small).