Many thanks to Mac and John for their very wise replies to my query,and will take note and ponder where to go from here,hopefully taking more sharper photos.Thank you!!

Thanks to Michael & G for your advise, Points taken.I am quite happy with the lens I have, I just thought by having the wider lens might give me a greater Depth of Field and sharper images

As a fairly new starter to photography and just recently bought a Pentax DL2 with a Pentax DA 1:3.5-5.6/18-55 mm lens & Sigma 55-200mm 1:4-5.6 lens.And as my main interest is mainly Landscape and Beach photography do I need to buy a wide angle lens. I would appreciate any advice given. Thank you ---Evets