Canon Powershort

Photography questions?
Im a beginner photographer. I have a Canon Powershort S51S. I dont like using flash often because I like to give it the “without flash” artistic feel. When I put the flash lid down, it automatically calibrates what the picture will look like in the LCD screen. In darker, night shots, It automatically makes the picture darker. When on an SLR camera I can take off flash and make that shot brighter a lot easier. If I raise the ISO speed then the pictures come out more grainy and noisy. If I put it on custom mode and manually adjust the shutter speed and aperature, it never comes out ‘just right’. Its always too bright or too dark. I want to know how I can take dark shots without flash. I know I can increase the shutter speed, but what good does it do me when the only clear shot works at a 15 second shutter speed…even 1/8 speed is slow. Any advice would be greatly appreciated.
This Canon model is NOT an SLR. Its just an advanced style point and shoot.
Can you please upload a photo that was taken at ISO 1,600 to, say, http://www.flickr.com so I can see what it looks like?
I had to look up your camera’s specs- and actually found some photos taken with it here: http://www.flickr.com/cameras/canon/powershot_s5_is/
For night shots, for example, this one http://www.flickr.com/photos/guywaine/2410456556/meta/ the ISO was set at 200 and the shutter speed was at 1/15 of a second. The aperture was at wide open (f 2.7). It looks pretty clear to me. (Must have been on a tripod or something).
Looking forward to seeing your photos so we can help you.
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