Auto focus speed K5 vs K20d??

If I were you I'd take one break from trips and get a K-5 for the future trips

The K-5 & DA* 60-250 combo is still pathetically slow, the K20 & Sigma 100-300 F4 combo was faster.Shot a football match with each of those combos and missed an awful lot more shots with the 60-250.

It is slightly better overall but still not a patch on a D300.

Its definately faster and more accurate than k20d. Not tried it on the ultimate test - dragonflies in flight but it certainly did ok with puffins in flight, except with cliff or sea in background (most cameras if not all would struggle there).

Which is an important point. AF is not just about the body. The 60-250 is notorious for being slow, whatever the body.

G

The lens certainly makes a difference. AF with the DA18-135 is very fast and rarely hunts.

Is it faster then the DA40?
Tough question right

I have not done any tests but subjectively both the DA40 and the DA18-135 seem to lock on to AF very quickly. Perhaps the silence of the DA18-135 makes it seem a more instantaneous and effortless process.

This is one reason why I haven't really considered a DA*60-250 as an upgrade over my sigma 135-400.

On the K-5 my 135-400 zips into action and focusses quickly, while the 50-135, although faster on the K-5 than it was on the K20D kind of gets there eventually and I miss shots.

But the DA*50-135 is a joy to manual focus though, very nice for portrait work for example.

Couldn't agree more.

But the vast majority of my shooting genre is of dynamic subjects. i.e Wildlife: species: homo sapiens

I had been planning to switch my Sigma 50-150 for a DA*50-135 when I'm in the UK this summer. Currently in negotiations over the sale of the Sigma.

However, this thread has sewn doubts in my mind. Its current price (+ a tax rebate as a non-EU resident), the weather-proofing, the option of being able to couple it with the F1.7 TC, and its slightly better IQ (though I understand the gap is very narrow here, and I've been very happy with the Sigma) had convinced me to trade in the Sigma. But is this unwise given the DA*'s inferior focusing (even on a K5), particularly when my chosen subject is also homo sapiens?

Is the focusing of the DA* so much inferior to the Sigma on a K5?

What do people think I should do?

Well I can only speak from my own experience. The focus speed on my DA* 50-135 is really slow compared to my other, non SDM lenses.

It's a real shame as the 50-135 is indeed a fantastic lens IQ wise.

I guess it depends on what kind of shooter you are. If you don't need fast AF then the 50-135 is a no brainer.

If you want to capture moments quickly then I would advise a non-SDM lens which responds faster.

My 135-400 Sigma's IQ isn't that far behind my 50-135, but it focusses much quicker

I have no experience of a Sigma 50-150, but if it's the same IQ as my 135-500 I'd keep it.

Out of interest, does anyone have experience of the DA17-70 and the DA*50-135?

I know people grumble about the former, but in my experience it's been fine - particularly on the K5.

Thanks, Smeggy. If it was down to IQ I'd stick with the Sigma, which really is very good indeed. However, there are the other factors too which complicate matters.

Well I don't know about the DA17-70, but My Sigma 17-70/2.8 is excellent quality. I'm actually surprised given it's not even an EX.

I've posted a few photo sets here in the 'Your Photos' sub-forum. the EXIF's should all be intact and a significant amount of them are taken with sigma lenses.




What other factors?

Smeggy, I was wondering about the AF comparisons between the DA & DA* to see if I could get an impression of how the 50-135 might behave. I have the DA17-70 and if the 50-135 is comparable AF wise, I could certainly live with this.

Other factors: compatibility with the Pentax TC, WR, and to a lesser extent the recent drop in price (when I got the Sigma the difference in cost made the choice a no-brainer).