aichup,
just saw yr series on yr Iran trip. Pretty nice images.
just some of my thoughts after seeing your images. btw, I am planning a trip to Iran at the Caspian region in May 2010.
There's limitation with a point & shoot compact camera. Go for a SLR which will give you more creativity possibilities. For landscape, you will need wide angle lens to capture the vastness. The use of colour ehancement & correction filters are also an important aspect of landscape photography. Also, you cannot leave home without a tripod for landscape photography.
In such secaries, you need the following filters:
1. Polariser - to saturate the colours & cut out stray lights
2. Neutral Density (graduated) filters - to balance out the foreground & background contrast & light level differences.
For portrait, the 35mm lens for environmental portrait is desireable or the 85mm lens to get what Steve McCurry do for his Afgan gal shot ie, close up protrait. It will be good to note that if you have a small flash use it to shoot the portrait, it adds a spark in the eyes of yr subject making them more "alive".
Hope that helps.
if you want some guidance, you can takle a look at my website.
www.jeffryanstudio.com