i would go with the two lens kit.
yes, 18-135 doesn't require you to switch lenses, but as far as my experience with lenses (although im not too familiar with these for canon) a wide range of zoom usually comes out as softer images.
as far as my experience go, lenses with shorter zoom ranges has higher and sharper images. lenses with longer zoom rangers are often softer but they make a good walk around lens since you don't have to change. i used to have an 18-250mm after the first day, i knew i had to let go of it. after 3 years, finally got rid of it and i am not regretting it.
secondly, what aperture lacks, you can make up for with the telephoto lens to get a feel for DOF using 55-200mm
thirdly composition is something to learn, but one thing that is also a must is to learn how to compose in restrictions to telephoto lenses.
with a 18-135, it's easy to just zoom out to get the necessary composition. that's not true for telephoto lenses. and you will feel quite restricted if you don't know how to use it. as recommended in portraiture, telephoto lenses work better because it limits distortions.
try composing with a 70mm. it is actually quite hard to do especially if you are just starting. what you have is a 55mm, and that's a good way to begin to learn with. and knowing you can't zoom out wider than that, you have to learn to adjusted and readjust yourself instead of the camera. i had a 40mm-135 (i think) for an olympus.. even for a 40mm, composing is already quite hard. this is a must if you want to do portraiture. my friends recommends 70mm+
i would recommend a two kit lens, simply because you need to learn the benefits and its restrictions of having both wide angle and telephoto lenses.
---------- Post added at 05:09 PM ---------- Previous post was at 04:55 PM ----------
Originally Posted by johnnybatu
As to switching lenses, madali lang sya. Just make sure you do it quickly and avoid dusty conditions.
tilt the camera down as to make sure you don't get dust inside the camera body.