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03-28-2015, 04:36 AM   #16
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QuoteOriginally posted by biz-engineer Quote
K-3 CDAF does not work with Tamron 70-200 f/2.8., while the CDAF and PDAF work great with this lens and K-5 /II/IIs.
The image quality/contrast of the Tamron 70-200 is much better than 70-300. The 70-200 is full frame compatible.
Could you please elaborate / provide sources?

03-28-2015, 05:01 AM   #17
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Sure: https://www.pentaxforums.com/forums/172-pentax-k-3/288839-focus-issues-k3-lens.html

You can buy one to be sure.
03-28-2015, 05:19 AM   #18
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QuoteOriginally posted by biz-engineer Quote
The thread referenced has widely different results reported. One user reported CDAF was worse on his copy of the lens on his k5 than his k3. Another reported that the manufacturer said live view auto focus was unreliable on the lens since it predates CDAF. It really isn't a clear thread with strong data to base anything on other than the fact that the lens may have focus reliability issues with CDAF.
03-28-2015, 05:45 AM   #19
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QuoteOriginally posted by biz-engineer Quote
Thanks and interresting to know... and well when we think of it, not that important on a reflex But I understand this can be anoying !

03-28-2015, 06:14 AM   #20
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I would go for the K-3. I have both and the difference is night and day. I hardly use my K-10D anymore. A year or two later when you consider your next upgrade, the lens will still be available and probably for a lower price.
03-28-2015, 07:25 AM   #21
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QuoteOriginally posted by Nicolas06 Quote
Thanks and interresting to know... and well when we think of it, not that important on a reflex But I understand this can be anoying !
Well, I bought the K-3 because the K-5 had no issue with all lenses except that it was not able to lock AF with my DA*300 (the K200 reliable lock AF with the DA*300 and all other lenses). The K-3 now can lock AF with the DA*300 reliably, but it cannot perform a CDAF (liveview) with the Tamron 70-200. But I did not care much, because I don't think I'll ever use liveview with the Tamron 70-200.
03-28-2015, 07:34 AM - 1 Like   #22
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I had a somewhat similar question a few years ago and upgraded to K5 from K100d Super, and continued to use my DA 55-300 rather than change it. I believe it met my objectives. Could I have achieved them with the lens change? Probably not. I was looking for a one-stop improvement, and faster fps. The lens could give a one-stop improvement, but would not improve the fps at all. And, I reasoned that I get the one-stop improvement with lens aperture, but would lose on depth, which might make it too hard to get the shot of something moving in focus. And then, the K100d Super would just not fire at all if it was not in focus. So with the K5 I knew I could just crank up the iso and fire away. I concur with some of the responses above - evaluate in what way the current setup is inadequate and address your needs from there. Photos from the Tamron 70-200 look great, but I was happy with the 55-300 images. With the 200 vs 300 max zoom you may run into cropping issues also. With the current lens and K3 you would also have a lot of pixel headroom to work with. With the 70-200 and K10 you are keeping both on the low side.
03-28-2015, 08:16 AM - 1 Like   #23
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All, thank you for the great responses- you've left me a lot to think about or consider. I have a game to go to this morning, but after I return I respond to the questions presented. I just wanted to give you all a quick thank you first.

03-28-2015, 08:42 AM - 1 Like   #24
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QuoteOriginally posted by biz-engineer Quote
K-3 CDAF does not work with Tamron 70-200 f/2.8., while the CDAF and PDAF work great with this lens and K-5 /II/IIs.
It is my understanding based on other user reports on this site that the CDAF issue with the Tamron 70-200/2.8 extend to the K-5 series as well. I know that you have previously reported no problems with K-5, but according to Tamron, the issue is with CDAF in general (not clear if this is limited to the Pentax implementation). Clearly, there is some variability in this area.

As for K-5IIs pricing, current U.S. pricing from reputable sellers is about $650 - $700 USD, body only. K-3 pricing is about $750 - $850 (B&H $799). My 2 cents? When I bought my K-3, the K-5IIs was about $100 less. I would make the same decision today, if for no other reason than better focus tracking.


Steve
03-28-2015, 09:27 AM   #25
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for what it's worth, the Sigma hsm version doesn't cdaf either without a firmware upgrade. If you want silent AF, it's pretty darn fast with a K3.
03-28-2015, 12:06 PM - 1 Like   #26
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QuoteOriginally posted by stevebrot Quote
It is my understanding based on other user reports on this site that the CDAF issue with the Tamron 70-200/2.8 extend to the K-5 series as well. I know that you have previously reported no problems with K-5, but according to Tamron, the issue is with CDAF in general (not clear if this is limited to the Pentax implementation). Clearly, there is some variability in this area.

As for K-5IIs pricing, current U.S. pricing from reputable sellers is about $650 - $700 USD, body only. K-3 pricing is about $750 - $850 (B&H $799). My 2 cents? When I bought my K-3, the K-5IIs was about $100 less. I would make the same decision today, if for no other reason than better focus tracking.


Steve
For $100 difference the K3 is a FAR FAR FAR better choice than K5-IIs. To me the question would be if you can find something far cheaper than that.
03-28-2015, 12:07 PM   #27
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QuoteOriginally posted by biz-engineer Quote
Well, I bought the K-3 because the K-5 had no issue with all lenses except that it was not able to lock AF with my DA*300 (the K200 reliable lock AF with the DA*300 and all other lenses). The K-3 now can lock AF with the DA*300 reliably, but it cannot perform a CDAF (liveview) with the Tamron 70-200. But I did not care much, because I don't think I'll ever use liveview with the Tamron 70-200.
I never saw issues on DA*300 with the K5... I suppose some have it but if you had a K5 and a new Da*300 that could not lock focus on it, I would have asked for a repair/exchange under warrenty.
03-28-2015, 12:48 PM   #28
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QuoteOriginally posted by Nicolas06 Quote
I never saw issues on DA*300 with the K5... I suppose some have it but if you had a K5 and a new Da*300 that could not lock focus on it, I would have asked for a repair/exchange under warrenty.
I return the first new DA*300 (could not AF, and SDM motor making noise, and the packing had been already opened and some dust was on the front element of the lens...), I returned it to amazon described the behavior of the lens, they sent me a new one from Italy brand new with a 4 years guarantee seal !!!. The new one worked better but the K-5 was still not able to lock AF 100% of the time, and not able to lock with the 1.4 TC. Half a year later I purchase the K-3 which worked fine with the DA*300 and DA*300 + TC. I was at the Red Bull Air Race... beside guys with huge Nikon equipment, I was laughing to see them with 5 kilos of gear (just thinking how much money their paid to photograph airplanes...) But the difference that I've found between the K-5 and K-3 is the accuracy. The K-5 won't lock if not perfectly in focus, while for the same focus, the K-3 accepts to lock... my understanding is that the K-3 PDAF favors speed. In this post, advice was requested regarding the purchase of a Tamron 70-200 (keep old camera), versus purchasing a K-3 (keep the old lens). Examples from DA*300 and Tamron 70-200 below.
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Last edited by biz-engineer; 03-28-2015 at 01:05 PM.
03-28-2015, 01:01 PM   #29
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QuoteOriginally posted by biz-engineer Quote
I return the first new DA*300 (could not AF, and SDM motor making noise, and the packing had been already opened and some dust was on the front element of the lens...), I returned it to amazon described the behavior of the lens, they sent me a new one from Italy brand new with a 4 years guarantee seal !!!. The new one worked better but the K-5 was still not able to lock AF 100% of the time, and not able to lock with the 1.4 TC. Half a year later I purchase the K-3 which worked fine with the DA*300 and DA*300 + TC. I was at the Red Bull Air Race... beside guys with huge Nikon equipment, I was laughing to see them with 5 kilos of gear (just thinking how much money their paid to photograph airplanes...) But the difference that I've found between the K-5 and K-3 is the accuracy. The K-5 won't lock if not perfectly in focus, while for the same focus, the K-3 accepts to lock... my understanding is that the K-3 PDAF favors speed. In this post, advice was requested regarding the purchase of a Tamron 70-200 (keep old camera), versus purchasing a K-3 (keep the old lens). Examples from DA*300 and Tamron 70-200 below.
My understand is that your statement is just that the K3 AF is better. But for sure the DA*300 would get focus on K5 on a still contrasty subject in good light.

So to me this is not DA*300 not working with K5... This is overall better AF with K3.
03-28-2015, 02:08 PM   #30
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QuoteOriginally posted by dms Quote
Why do you want the faster lens? To isolate the players/narrow dof--then the lens.
Because you want faster shutter speed? Either lens or camera.
If the photos are too noisy and you want lower iso (for the k10d), then likely the k3...

But I should add I don't use AF, and that aspect is not something you mention, but may be an issue for K3 vs K10d--and w/ a faster lens the focus is more critical. If you manual focus--neither camera likely works well w/o a new screen.

One other point--getting a new camera may be problems w/ your workflow, and a new computer is costly.
These are all good points... My desire for the faster lens was to isolate the player and to increase contrast for less post processing. I haven't had a need to sharpen my images, most of he games are in bright daylight and so shutter speed hasn't been an issue. With respect to ISO, I rarely like to push it above 200 or 300 on the K10D because of the noise.

I depend on the AF, so that is one reason the K3 is very attractive to me.

Lastly, my PC isn't the greatest but I don't do a lot of post processing beyond cropping, white balance, and tweaking the contrast. I shoot only JPG.
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