What are essential lenses for dSLRs?

Hey all.
I finally decided to dip into the dSLR market. I just bought a Pentax K100D since I was quite impressed with the pic quality and esp the price. It came with the 15-50mm lens. It's only 6MP but I'm not really looking to blow this pic beyond at most 8.5x11 prints. What other lenses do you suggest (or essential to your arsenal)? The big draw for me was the fact all Pentax SLR lenses are compatible with this camera so I'm hoping to get some deals in pawn shops, craigslist etc. I'm a relative n00b to this and would like to get more serious through practice and forums such as this.
I definitely will grab a telephoto lens but what do you suggest is a good compromise between it being too bulky and well, usability .
TIA.

The first lens I bought to go with my kit 18-55 lens (Nikon) was the 55-200VR lens. So my recommendation: a good zoom.

It really depends on what type of photographer you are.

Interested in Portraits? Get a good mid-range or long range zoom...or fixed 50mm or 85mm primes.

Landscape? Get a wide-angle

Nature? Get a long zoom

Personally, I enjoy street/travel photography and I love my 12-24mm Nikkor. I visualize and frame my shots better with it then with all my other lenses...

Hope this helps!

Lenses are tools. So, pick the right tool for the job. Decide on what you want to shoot, what lighting condition will be, what perspective you want etc. and then get the lens for it.

First lens i picked up was a 50mm f/1.8 for my canon.

A definite must buy IMO. Best bang for the buck. The results are just amazing. I went with a nikon of course. Not sure how the canon version is.

Originally Posted by skev13

First lens i picked up was a 50mm f/1.8 for my canon.

Originally Posted by robattoronto

A definite must buy IMO. Best bang for the buck. The results are just amazing. I went with a nikon of course. Not sure how the canon version is.

Tis was my first lens but just wasn't practical enough for me. I sold it and got the 18-200. I do a lot of traveling around with my gf so this lens allows me to be flexible. Plus it's light and easy to use even for my gf. I

I got the 50mm 1.8 Nikon lens when I first started and guess what? I don't really use it. I just don't enjoy shooting in that range on an aps sensor camera.

Decide what type of photography interests you and choose the lens accordingly.

It's like buying a car. No sense in buying a 7-seat minivan if you're a bachelor. Same goes for lenses. No sense buying a 70-300 superzoom if you won't use it.

50mm doesn't really suit me either, my 50mm lens hasn't been attached to my camera in over 6 months.

As mentioned, you get the lenses that will get you the picture you want. Whether that is a wide angle zoom/fisheye, telephoto, macro, or otherwise. There are some very good lenses that can do double duty like the Tamron 90mm macro, or Nikon 105 VR macro, which also do well as portrait lenses.

Primes may/may not be your thing. While they do force you to be more creative in your composition since you can't "lazy-hand zoom", it may not be your style.

Thanks for the ideas. I think I'll get a better zoom lens. I'm just starting out so I have no idea what type of photos I'll do just yet
I like candid people shots, and will probably do some macro type close-ups of insects/flowers etc.
What do you use the most is my next question.

I would say, you need a wide angle to mid range, then mid-range to short zoom, then short zoom to big zoom.

Myself, I'm using 17-85mm for wide-angle and walk around indoor/outdoor, 50mm f1.4 for STRICTLY indoor (this lense has horrible CA outside), and a 70-200mm for when I stalk peo..uh I mean for sports and portraits..

I'm pretty much covered from short to long range. However, I plan to go all L eventually. L glass is expensive, but worth every penny.

Money money.... or work with what you have!

Lens are expensive stuff, but they can be good investment! If you avoid 3rd party brand (except for CZ). When I see investment, I dont mean making money from it, simply holding a good resale value.

my 2 cent

Originally Posted by 2000fordfocus

Money money.... or work with what you have!

Lens are expensive stuff, but they can be good investment! If you avoid 3rd party brand (except for CZ). When I see investment, I dont mean making money from it, simply holding a good resale value.

my 2 cent

I doubt I'll go overboard peripheral-wise for this new hobby, but I'm thinking long-term. The Pentax has all the features that I want (for now ). I do want quality when it comes to lens/filter equipment and am willing to wait for a deal

Originally Posted by sfu_lifer

I doubt I'll go overboard peripheral-wise for this new hobby, but I'm thinking long-term. The Pentax has all the features that I want (for now ). I do want quality when it comes to lens/filter equipment and am willing to wait for a deal

For me, I can about features like 10fps or ISO 6400 quality, etc....

What I want is quality sensor that will capture a lot of DR, without annoying blown out highlight(google this term if you a unsure what I am refering).

Originally Posted by 2000fordfocus

What I want is quality sensor that will capture a lot of DR, without annoying blown out highlight(google this term if you a unsure what I am refering).

This is often due to the meter of the camera... some will blow highlights more than others.