Pentax DA 50-200mm lens

[geotography]

I am thinking about adding a Pentax DA 50-200mm lens to my gear. The reviews are good and the price is quite good.

My specific question: It is said that the focus is somewhat soft at the full telephoto end. I would expect that to be the case with most hobby-level lenses; but at what focal length do you think the sharpness of focus would become intolerable?? 175mm?, 180mm? more? less? Guesses?

Thanks

geo

[jdepould]

Please don't cross-post, one thread is enough.

[geotography]

Sure. Will you be deleting or shall I.

[Mr Guy]

This may belong better down in the Pentax forum. I've got that lens and I like it quite a bit. I've only just started with my new camera, so I'm not the end all be all of what can be done with it, but I haven't noticed an unbearable amount of softness with it. I was looking for some good examples I've taken recently, but it's hard to tell which flaws are caused by the lens and which are caused by my hand holding technique!

For example, this one WOULD be a perfect shot to show the capabilities, but it's got pretty bad motion blur that's really noticeable in the larger pictures on the rocks:




There was a good bit of distance between me the guy fishing, at least a couple hundred meters (although I'm not sure the exif default of 2k is right).

Camera: Pentax K110D
Exposure: 0.001 sec (1/1600)
Aperture: f/5.6
Focal Length: 200 mm
Focal Length: 2000mm
ISO Speed: 200
Exposure Bias: 0/10 EV
Flash: Flash did not fire


Also you'll notice that I didn't get the autofocus quite right, and the water behind him is actually in focus while he's not. Since then, I've learned how to use the camera's selective focus points!

[Nicole]

Originally Posted by geotography

Sure. Will you be deleting or shall I.

I'll do it Everything's moved together into this thread now

[geotography]

@Thanks Nicole . I promise I won't cross pollinate, er I mean cross dress...no I mean cross post anymore.

@Mr Guy: thanks for your reply. That's helpful to me. I mean the reviews are quite good for amateur-level glass and the price is irresistable for a tad more reach which I do not yet have in my bag.

[GEli]

I'm not so fond of this lense. I've only played with it in the shop, taking a few test shots, but it reminded me a great deal of the kit lense in that it's almost intolerably soft when wide open at any focal length (though it's slightly worse at 50mm). The photozone.de review agrees with me and gives it a pretty nasty rating of 2/5 for value and 1.5/5 for optical quality.

However, all is not lost! If you only ever intend to use this lense outdoors, where you can stop down to f/8 or smaller all the time, it should be rather useable. You might also consider taking a look at some of the older Pentax medium to long telezooms. I have a Pentax A 70-210mm f/4 that's just gorgeous through its entire range. It's a manual focus lense, so wouldn't be too useful for sports and the like, but is perfectly acceptable for most anything else even with the standard focusing screen. Here is a (rather large) example of a pretty heavily cropped image I took with this lense at f/4, 210mm on my K10D. It's been slightly desaturated to fit into a series, but this is more of an example of the level of sharpness (this is an unsharpened image) you can achieve even wide open with this lense. Here is an example of the 1:4 macro it can do at the 70mm end. It has a nice focus lock for when you're doing macro work and as you can see is rather sharp through the whole range. The only negatives for this lense are the manual focusing and the weight. It's a bit hefty at around 700g, or the weight of a K10D body without the battery. I got mine for $100 from a local shop used, but I overpaid in the excitement of having finally found a copy - you can probably get it for less if you buy from another photog rather than a shop.

[jdepould]

Have you looked at any Sigmas or Tamrons?

[Nicole]

Originally Posted by geotography

@Thanks Nicole . I promise I won't cross pollinate, er I mean cross dress...no I mean cross post anymore.

So cross breading isn't out of the question then... I suggest a platypus with a lion... or perhaps a monkey with a shark Ok, done thread jacking lol

[geotography]

@Nicole:

@Jdepould: Thanks for the tip; in fact, I was studying the Tamron 70-300mm last night. For a very inexpensive, amateur piece of glass, it appears to be a contender for the subject Pentax lens. I basically want an outdoor/day lens with some reach that I can use with a relatively fast shutter speed (1/250 to 1/500) without having any major softness or exposure issues.