Sharp Long lenses for my K-30

Im looking for some long range (300mm to 500mm) lenses for my k30 which I bought a few days ago with the 18-135mm WR lens.. I have no experience with dslr's before this one so i'd say this lens is reasonable sharp and well built. (but I have no other lens to compare it with so what do i know)

when looking for some long lenses my priority (even above reach) is sharpness.. i'd rather go for a sharper 300mm max focal length than a softer 500mm max. though reach remains the next priority. so when searching for lens as a newbie I looked from the cheapest to more pricier lens..

first i saw those samyang, welimax and opteka ones.. which i read are not sharp at all as they are so cheap. so with further search i made a list of these

DA 55-300 (either the WR with without)
Sigma 70-300 APO DG
Sigma 170-500 APO DG
Sigma 150-500 APO DG

[according to what i read it seems if i was to go with any of these sigmas i should pick the APO and DG ones as they produce better results.]

My questions are,
Which of these are the sharpest?
How big the difference is to the second sharpest in the list..
Would you like to add some more to the list?

i read that 150-500 beats the 170-500 at the long end and over all [if so]
150-500mm vs 55-300? is the DA sharper? if yes, how much? does the 150-500 lose any sharpness at the 450-500 range? and how is the 70-300mm compared to the DA 55-300 considering sharpness?

Why the seemingly obsessive priority on sharpness?

While I appreciate a crisp image, IMO the emotional content of the image is far more important than pure sharpness.

And don't forget you can increase sharpness in post processing anyway.

The IQ Quality of a lens is far more than just sharpness. Of course is sharpness floats your bloat then it's not for me to dictate otherwise, but I would consider re-evaluating your approach to photography if sharpness features so heavily on your wish list.

If by sharpness you really mean detail then you can either get this from a high MP sensor or buy spending a ridiculous amount of money for a long range telephoto and stopping it down to it's sweet spot.

The other question is, do you want sharpness across the whole frame or just in the subject area. It's an important question as there's no need for ultra detail/sharpness to render bokeh as a back drop to the in focus "Sharp" subject.

Personally I think any of the lenses you list is not going to compromise your experience of viewing images taken with it on glass technical grounds.


It's probably worth weighing up your available funds with the offerings on focal range and aperture.

A lot will depend on what weight you want to be humping around IMHO. I've both the 55-300 and the 150-500. They're both superb. There's certainly a lot more reach with the big Siggy, it's darned sharp, and if you can afford the OS version very forgiving. But the downside is it's a heavy old lump.

What's the subject?

You could check out the lens reviews on ePHOTOzine and Photodo, as well as many other sites. The only way to be sure a lens will live up to your expectations though is to try it out. Maybe a shop with the lenses in stock would let you shoot a few images with your camera body?

Im just new so im not the best with using these terms.. yes by sharpness i mean the overall IQ, detail and that bit of pro(ish) looking vibrance.. i really like those things in an image.. i dont like those soft and dull images that some lens produce at their high end and manage to pick no details or bright and beautiful colors.

I would carry heavier lens for better images.. subjects would be some birds, animals, nature, and action that is some distance away.. and at the long range i want the image to stay sharp and vibrant.. otherwise that extra reach would be pointless for me.

Toni, I have first-hand experience with three of the listed lenses - all bar the obsolete Sigma 170-500, which the 150-500 superseded.

By general consensus, the DA55-300 outperforms the Sigma (and Tamron) 70-300 in every department, providing better IQ as well as slightly longer range. My own example has been a bit inconsistent, but I bought it used from a retailer and suspect it's a rogue sample. A friend acquired one for motorsport and general use and has had terrific results. The best advertisement, though, is probably the excellent David Storm's recent thread in praise of the lens - see link. That should provide all the evidence you need.

As for the 150-500, you need half-decent light, because at f6.3 it's a little slow at the long end, but in terms of value for money it's hard to fault. I've become used to lugging it about and usually have a monopod attached, simply because I find it a comfortable carrying aid (lens on shoulder, monopod in hand).

It is acceptably sharp throughout its range: here are a few samples.


With monopod, 1/100 at 250mm


Panning with monopod, 1/60 at 270mm


Hand-held, 1/640 at 440mm

Happy hunting: if you have any specific questions, feel free to drop me a PM.

f8, 1/125, 1100ASA @ full stretch.

I have the sigma 70 -300 apo jobbie and it's awful over 250mm - in fact best used up to 200mm (which shows in the exif as 210mm??)

I almost bought the sigma 150 - 500 a few years ago but once I read that it is actually closer to 450mm than 500mm in reality and that to keep it sharp you need to keep to around 450mm not 500 (as shown on the lens) then I decided against it, however there are plenty of images around to suggest that it is capable of sharp images

I use old primes for the time being, of course they are more work but my old mf 300mm and 400mm primes win hands down against the 70 - 300 at it's long end.

Why not look into the Pentax da* 300mm - an excellent lens by all accounts

The absolute best for Pentax (excluding discontinued lenses and the 560mm) is a DA* 300mm f4 and a Pentax 1.7x adapter for 500mm. Nothing else comes close imo although I do use the Sigma 50-500mm os quite a bit because of the zoom.

+1

I use both above mentioned with great satisfaction.....but still looking for one A*300/2.8 at a reasonable price ....

The 1.7x Adapter is still available NEW from Japan

link

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I use both a DA*300 and for the extra distance a 150-500 on a K30 and a K5.

The 300 has produces a superb Image quality. The 150-500 is very good indeed. I would advise use of a tripod to stabilise and the benefits at the long end pay off.

but the pentax 1.7x adapter is nowhere to be found.. let alone finding a good used one for a good price.. do know of any for sale?

so guys, the 55-300mm and the 150-500 both produce similar IQ? and both are equally sharp at their respective long ends?

you'd probably need to compare individual lenses at this point.