hahaha to creampuff and pinhole cam, you must understand that there really are some people who must have that extra reach. i am one of them
there are some shots that you just cannot take without zooming in that much, and you don't have the time to move yourself to compose the shot.
to the threadstarter - if you are sure you want it, go get it. the first lens i searched for immediately after i got my k-x was the Pentax 18-250. I also spent a lot of time thinking about whether to get the 55-300 instead to couple with my kit lens(cheaper alternative). On a student's budget, it was important for me to make the right decision!
I bought a 2nd hand Pentax 18-250 for $400 in the end. In a way, the low price made the decision for me and having experienced it, i am sure it was the right choice for me. :bsmilie:
For 1-2 months after buying it, i hardly used it. Because i was new to DSLRs, the photos from the 18-250 were not coming out as bright and vibrant as i wanted. I even contemplated selling it, but i held on to it for a while. I next got a 50mm f1.4, also second hand, and with it i learnt all that i know now regarding how to make my shot look how i want it to look.
After this 1-2 month hiatus, i clicked on my 18-250 again, and i am so happy with it! Here is my humble opinion.
Pros.
1. 18-250 is versatile. Really versatile. At 18mm the wideness makes you happy, and at 250mm the zoom makes you even happier. Whatever you want, you can take with this lens. This lens was also voted the King of Superzooms on the Pentaxforums.
2. Why 18-250 over 50-200? Cos you get a 2 lens combined into one with further reach. And when you want to take the photos that matter to you, like going out with friends, at parties, on excursions etc, you do not really want to change lens to transit from below-50mm to above-50mm. I find it an hassle, you might not.
3. Why 18-250 over 55-300? Exact same reason. In addition, the greater the zoom, the more your hand shakes get amplified and that will contribute greater to the blur pictures you might have.
Here are the downsides and why i am okay with them. You might, too
1. There is distortion at the extreme ends. Meaning you see a slight curvy distortion to straight lines. But, unless you go and shoot like a brick wall or a lot of vertical lines, you will hardly notice it. After all, you are shooting people and scenery. I have been happy with the images shot at 18 mm so far. That being said, i believe i got a very decent copy of the lens.
2. This lens does not work very well in low light settings. The 18-250 works best outdoors where there is plenty of sunlight. In dim settings, you will need a longer shutter and/or higher ISO. While higher ISO is not much of a problem for the k-x, a longer shutter will amplify your blurness of the picture. Especially at the longer zooms, sometimes when there is too little light i can't use the 250 end cos it will be too blur. You need to work on your holding techniques on this one.
To this, there is no real solution. You will have to adjust the exposure, and see what the shutter can give you. Then here is where a fast prime comes in. Above i talked about my 50mm f1.4. It takes care of all of my low light needs. You need a superzoom? Then you NEED a fast lens too.
3. Zoom creep, meaning the lens will extend when you tilt it downwards beyond around 30 degrees to the horizontal.
Well, the lens is heavy, so what do you expect? I dun find it an issue, cos when u are shooting, you will be holding on to the lens anyway. There is a lock at 18mm that will hold it in place. Beyond 18mm, no lock and hence can creep. However, since i don't have a tripod yet my lens hasnt crept on me when i do not want it to yet. Not an issue. I do wonder why people should be too particular over this point though. I feel it's more of a feature of a heavy lens than a disadvantage.
4. Vignetting. I do not really experience it. My shots turn out fine. But like i said i probably have a decent lens with me. Or maybe it has always been there but i think there isnt? Haha. But either way i am not turned off in any way by this point.
In conclusion, go and get your 18-250!! :devil: It will satisfy you. I have experienced many occasions where i use a long zoom at one moment to catch someone with a thinner depth of field(above 70 mm, you get rather pretty bokeh already), and the next moment the 18mm comes in to take group shots.
For low light shooting and wonderful bokeh, a prime is a must. If you think and shoot the way i do(which you probably do), go with this 18-250 plus a prime setup first. I cannot buy too many lenses or my parents will killlll me, so this is what i can tell you about this setup and this lens. The 18-250 has made me very happy indeed