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03-18-2017, 01:23 PM - 1 Like   #31
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Seen this thread before, many times....too many to count. Some time ago there was a similar thread in which Norm wrote an excellent reply that encompassed all the things related to superb AF. It was very interesting and most enlightening...wish I could find it and post it here. The bottom line of it was that you can get it....for a price. You can't get a Lexus for the price of a Kia, it is simple enough, but somehow many don't want to recognize the facts of economy that relate to higher prices for more performance.

That said. I'll give you my often posted story. It is 100% true and not meant to be "Fanboy" fabulous, just the facts as I have encountered.

About a year ago my K5IIs was badly damaged in a freak accident. I loved it, best Pentax I had ever owned from the DS forward. Mrs Rupert, seeing I was brokenhearted offered to buy me a K1. Not being a total idiot, I quickly accepted her offer!

Now I have been Bigma 50-500 shooting for over 10 years...from the DS forward through many Pentax bodies. Every new model has "reported" better and faster AF....in most cases it was an illusion at best. I have spent countless hours while the Bigma hunted like a blind hound and my subject didn't wait for me to get a decent focus as the Bigma tried and failed to find focus in a timely manner. I learned new curse words, threw things over shots I missed, and lived with the general frustration that I read in your post. This carried over to my newest Bigma HSM OS model....some improvement over the old model, but still the hunting and failure to lock focus fast and sure...in particular in low light or brushy scenes.

So...the K1 arrived and I had a fresh battery ready. I quickly mounted the Bigma and went to work testing the "greatly improved" AF system. First shots of wildlife brought out some of my well used curse words, but in a different direction! Damn, son of a "gun", this thing is fast and accurate! It ain't no joke, it is like magic over my previous bodies, No hunting, zero, no waiting as it hunts back and forth......just bang with the focus confirmation and fire away! I still pinch myself to make certain I am not dreaming....here a year later!

In wildlife shooting you have only seconds to get a shot most of the time. Excepting the trained squirrels, animals don't sit an pose until you lock focus and snap, they are "off to the races" in just a few seconds. I keep my K1/Bigma on my desk ready to shoot, adjust settings a few time as day to be close to the available light needed. When a shot appears I need 2-4 seconds to pick it up, turn it on and lock focus. I get more keepers than not, and most I miss have no relation to slow or inaccurate AF......more about speed and light or not allowing SR to function.

You will see the underside of a Spanish dove maybe twice a year...maybe. You need to be fast and you need fast AF or you won't capture the very few seconds he is cooling his body with wings up. Few people ever see their colorful underside...I had only a very few seconds to pick up the camera, turn it on and point to get focus. Focus was instant. I got what I wanted.



Many hundreds more fit this same situation. My AF problems have ended with the K1. Even low light makes K1 shooting easy....

ISO 12800 1/80 handheld (ALL of my shots are handheld)


Now I am not a sports or action shooter, but with a fast top notch lens I think the K1 could and would deliver for me in that area without frustration.

I still have failures and not all shots are usable, but rarely is AF a cause of the failure. That's my story, and I'm sticking to it...and I'm sticking to my K1 when it come to the AF system it is the best Pentax has ever offered...and yes, it does cost more, but not that much...in fact it is a genuine bargain!


Best Regards! Get a K1 and some soap to wash that Canon talk out of your mouth!

03-18-2017, 03:31 PM   #32
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QuoteOriginally posted by Miguel Quote
What was frustrating was the lack of AF configuration at the level of control and sophistication that Canon offered and that made a big difference.
That's fully understandable if you know what you are doing. From what we often read, the K3 configuration is already too complicated for some users, so, they would be totally lost with the complexity of the 7D II settings which requires a dedicated manual.
03-18-2017, 03:41 PM - 2 Likes   #33
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QuoteOriginally posted by biz-engineer Quote
That's fully understandable if you know what you are doing. From what we often read, the K3 configuration is already too complicated for some users, so, they would be totally lost with the complexity of the 7D II settings which requires a dedicated manual.
Pentax really falls down in their User Manuals. They assiduously list every Control on the camera and every line and choice in the Menu, but they never describe how to configure the settings to accomplish a task or set up the camera for a style of shooting.

I am convinced if Pentax published a White Paper on AF many of these frustrations would go away. The same is true of Astrotracer, various Modes, Program Line selections and even Button Customization.

Despite having used their digital cameras since 2006 and having a basic grounding in their control logic since the MZ-S I think I've barely scratched the surface using the extended capabilities of the advanced cameras (K-3 and K-1).
03-18-2017, 05:37 PM   #34
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QuoteOriginally posted by monochrome Quote
I am convinced if Pentax published a White Paper on AF many of these frustrations would go away. The same is true of Astrotracer, various Modes, Program Line selections and even Button Customization.
This. It's a big failing of the brand. Pentax roll out all this good tech, but consistently fail to document it properly. Even my microwave has a thicker user guide than the K-1, for example.

03-18-2017, 08:49 PM   #35
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QuoteOriginally posted by biz-engineer Quote
That's fully understandable if you know what you are doing. From what we often read, the K3 configuration is already too complicated for some users, so, they would be totally lost with the complexity of the 7D II settings which requires a dedicated manual.
I disagree mostly. The newer Canon models like the 7D mk2 have five different AF use cases that are clearly identified. This makes it easy for most users to pick and test. You can also customize the three tracking variables if desired. Some of the other controls are less obvious, so it's imperfect like all camera brands. I frequent a few high traffic Canon boards with a lot of new DSLR users. It seems like they are OK enough figuring out the 7D AF. I also believe the Pentax shooter needing good tracking AF is exponentially savvier than these mommies and would take to a well Pentax AF system handily. If it existed.

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03-18-2017, 09:24 PM   #36
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QuoteOriginally posted by Miguel Quote
My advice would be to rent a 7D Mark II and the 100-400mm Mark II and see how that works for you. The 7D Mark II is the second most accurate AF system in the Canon line; the 100-400mm Mark II is an improvement over the first version, not a huge one but noticeable. An alternative would be the Nikon D500 and the Nikon 200-500mm lens which I hear is just excellent for the money.
Thanks for the info! From what I read, the IS on the 100-400 MkII is a big improvement over the original.

QuoteQuote:
I'll respond based on my real life experience using both a 7D + the 100-400mm L for many years as well as the K-3 + Sigma 100-300mm f4 for several months. I shoot birds and fast moving team sports like U-19 soccer and now college women's lacrosse.
Great! That's exactly what I was hoping for.

QuoteQuote:
I had left the Pentax world for Canon about 10 years ago when my job as a corporate photographer turned to shooting a men's soccer team that the company sponsored. The 7D was very good at that time, though noisy sensor wise, but sports is not fine art and there is wiggle room for NR. I still had a bunch of Pentax glass and when the K-3 came out I purchased it along with that Sigma and gave it a good long test over many months. Unfortunately the AF accuracy was about 60% of what the 7D offered--that was a fairly high bar for the time, so the K-3 was OK. What was frustrating was the lack of AF configuration at the level of control and sophistication that Canon offered and that made a big difference. I grew frustrated and sold off the K-3 and Sigma lens (which was detrimental to birds as its screw drive AF was noisy and scared them off).
That's good to know! One good thing about the DA*300 and DFA 150-450 is they they focus very quietly. Focusing quietly isn't much use unless a lock is also achieved. I had no problems with a brief test of the DFA but the DA*300 is a different story.

QuoteQuote:
For the record, I'm back with the Pentax K-1 which for art is just a fantastic camera. It was tough deciding between that and the 5D Mark IV (which is excellent image wise) but the pricing and value was unconvincing. The AF is superb. I'm going to rent the Pentax 150-450mm just to see, but in my experience everything AF with Pentax is second rate--not just performance but the configuration and the user interface. The thumb-based joystick on the newer Canon bodies is excellent for putting the AF points where you want them to be and the button layout is great for back-button focus. And the tracking is very good. As a postscript--I borrowed my friend's Nikon D500 for shooting birds and that was the best for AF, really top notch, but not cheap.
I'd love to hear about your experience with the K1 and DFA 150-450. FWIW I tried a friend's Nikon D3000 - much cheaper than the bodies being discussed here, but on a consumer zoom I found the viewfinder excellent and the AF very capable - however, AF on an 18-50 lens (I don't remember the exact focal range) is a totally different story to a long lens.

QuoteOriginally posted by Rupert Quote
Seen this thread before, many times....too many to count. Some time ago there was a similar thread in which Norm wrote an excellent reply that encompassed all the things related to superb AF. It was very interesting and most enlightening...wish I could find it and post it here. The bottom line of it was that you can get it....for a price. You can't get a Lexus for the price of a Kia, it is simple enough, but somehow many don't want to recognize the facts of economy that relate to higher prices for more performance.
OK, but the thread ended up being drawn in a direction which I hadn't intended. I was really looking for people who had experience with long lenses on Canon and Pentax and how that experience differed. I didn't really want to get into a long discussion about my skills as a photographer or my knowledge of the settings of the K3, because I've already been there. I already suspect that my DA*300 has an AF fault, and I'll look into getting it repaired, or at least serviced.

QuoteQuote:
So...the K1 arrived and I had a fresh battery ready. I quickly mounted the Bigma and went to work testing the "greatly improved" AF system. First shots of wildlife brought out some of my well used curse words, but in a different direction! Damn, son of a "gun", this thing is fast and accurate! It ain't no joke, it is like magic over my previous bodies, No hunting, zero, no waiting as it hunts back and forth......just bang with the focus confirmation and fire away! I still pinch myself to make certain I am not dreaming....here a year later!
That's great to know - especially considering that it was an existing third party lens. Certainly the Pentax AF seems to have improved between the K200, K7, K5 and K3. It may be that part of the solution would be to wait for a new APS-C flagship. I haven't seriously considered the K1 simply because most of my lenses are not full frame, and it seems a waste to have a full frame camera running in crop mode.

QuoteQuote:
In wildlife shooting you have only seconds to get a shot most of the time. Excepting the trained squirrels, animals don't sit an pose until you lock focus and snap, they are "off to the races" in just a few seconds. I keep my K1/Bigma on my desk ready to shoot, adjust settings a few time as day to be close to the available light needed. When a shot appears I need 2-4 seconds to pick it up, turn it on and lock focus. I get more keepers than not, and most I miss have no relation to slow or inaccurate AF......more about speed and light or not allowing SR to function.
Also great to know! When photographing birds, I'm generally walking around, and opportunities are very brief. They seldom give time for the lens to hunt.

QuoteQuote:
You will see the underside of a Spanish dove maybe twice a year...maybe. You need to be fast and you need fast AF or you won't capture the very few seconds he is cooling his body with wings up. Few people ever see their colorful underside...I had only a very few seconds to pick up the camera, turn it on and point to get focus. Focus was instant. I got what I wanted.
Cool shot!

QuoteQuote:
ISO 12800 1/80 handheld (ALL of my shots are handheld)
I'm amazed that you have an image which has so much detail yet seems to have very low noise despite the high ISO.

QuoteQuote:
Best Regards! Get a K1 and some soap to wash that Canon talk out of your mouth!
Thanks for the suggestion! It's certainly worth consideration.
03-18-2017, 10:29 PM - 1 Like   #37
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Whilst one can always chase the ultimate whatever, I find the DFA 150-450 speed of focus on a K-1 and K3 so far ahead of previous lenses such as pentax 300s and Sigma 150-500s that they are not compatitable. I've spent last week out in the bush with a mate who has a couple of K5II's and a sigma 150-500 and there is no compatison to the DFA 150-450 on more modern bodies.... such as what I was using.... I shot with his gear quite a bit as I was setting up some user modes for him, for birds in flight etc. If staying with one system was important to me (which it is), I'd rent the DFA first and if it met my needs I'd just get it.

Anyway Rob, sounds like your a bit like me, in that you like to explore and grab opportunity shots mostly.... the DFA 150-450 works well for me this way.

People talk about pentax autofocus as something really complex.... I don't see it that way for the most part. I'd take a pad and pen then head down the beach and just work through the various options methodically with some seagulls.... a pleasant afternoon and it would all be a bit more familuar.

The K3 (I see you have one) works well with the DFA, and as Norm has pointed out, is a good partner when shooting small things, with reasonable light, the focus system of the K-1 is a step ahead, and is a great combo when the light is less then perfect, or if you can get a bit closer and frame rate isn't a factor.

For me, the DFA 150-450 and K-1 has taken most of the frustration out of shooting moving things....especially in less then perfect light.... so I havent chased other brands.


Last edited by noelpolar; 03-18-2017 at 10:53 PM.
03-18-2017, 11:36 PM   #38
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QuoteOriginally posted by Miguel Quote
For the record, I'm back with the Pentax K-1 which for art is just a fantastic camera.
QuoteOriginally posted by Miguel Quote
The AF is superb.
QuoteOriginally posted by Miguel Quote
I'm going to rent the Pentax 150-450mm just to see
You seem to find the AF of the K1 better than K3's. Well, my experience having extensively used the K3 with DFA150-450 and K1 with DFA150-450 is that the K3 + DFA150-450 had the best AF tracking capability of all, getting between 80% and 100% keepers on birds in flight. With the K1, I get less keepers, the K1 AF seems to have some lag that does not exist on the K3. I shot both K1 and K3 with the same DFA150-450, and I sold the K3 to finance lenses, but I'm considering to buy back a K3 or wait for the next model. The DFA150-450 is very different from other Pentax lenses because it uses some form of step motor that allow the camera / lens to know the AF position, for instance there is no hunting, the lens AF goes in the correct direction immediately. The DFA150-450 AF is fast but not the fastest and speed does not seem to be the limiting factor, but position feedback seem to do the trick for tracking, typically, the DFA150-450 tracks very well what the DFA70-200 can't, surprising since the DFA70-200 is f2.8 we would expect AF to work better but no, the DFA150-450 tracks better. Sharpness wise, the DFA150-450 isn't as sharp as the DA300, but the AF makes all the difference. For having compared the DFA150-450 to alternative lenses, DFA150-450 AF is slower than Canon 100-400 II and slightly slower than Nikon 200-500 but faster than Sigma 150-600s and Tamron 150-600s. Also, the DFA150-450 AF speed is constant from 150mm to 450mm , so is the Canon 100-400 and Nikon 200-500, however, the Tamron and Sigma 150-600s AF slows down as focal length increases, for instance at 600mm the Tamron AF is ridiculously slow, much slower than Pentax AF.

Last edited by biz-engineer; 03-18-2017 at 11:50 PM.
03-19-2017, 03:05 AM   #39
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QuoteOriginally posted by noelpolar Quote
If staying with one system was important to me (which it is), I'd rent the DFA first and if it met my needs I'd just get it.
The minimum rental period on the DFA is 6 months, so I'd rather try the Canon first then I have a comparison. Staying with one brand is nice, but if I could get better results for a similar price, I'd like to at least consider it.

QuoteQuote:
Anyway Rob, sounds like your a bit like me, in that you like to explore and grab opportunity shots mostly.... the DFA 150-450 works well for me this way.
Cool. Glad to hear from a DFA owner.

QuoteOriginally posted by biz-engineer Quote
You seem to find the AF of the K1 better than K3's. Well, my experience having extensively used the K3 with DFA150-450 and K1 with DFA150-450 is that the K3 + DFA150-450 had the best AF tracking capability of all, getting between 80% and 100% keepers on birds in flight. With the K1, I get less keepers, the K1 AF seems to have some lag that does not exist on the K3.
Could it be because the K3 is looking through the sharpest part of the lens rather than the full frame?

QuoteQuote:
The DFA150-450 is very different from other Pentax lenses because it uses some form of step motor that allow the camera / lens to know the AF position, for instance there is no hunting, the lens AF goes in the correct direction immediately.
I noticed this when testing it. No hunting and taking the shortest path to the correct focus.

QuoteQuote:
For having compared the DFA150-450 to alternative lenses, DFA150-450 AF is slower than Canon 100-400 II and slightly slower than Nikon 200-500 but faster than Sigma 150-600s and Tamron 150-600s. Also, the DFA150-450 AF speed is constant from 150mm to 450mm , so is the Canon 100-400 and Nikon 200-500, however, the Tamron and Sigma 150-600s AF slows down as focal length increases, for instance at 600mm the Tamron AF is ridiculously slow, much slower than Pentax AF.
Great information, thanks!
03-19-2017, 04:46 AM   #40
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I've shot jets at airshows with the K-5 and 55-300 and the K-3 with 60-250, with and without TC. I actually got better results with the 55-300. But I think it slso depends on lighting conditions.

In general, I find Nikon AF to be more reliable for a similar price. And a stabilized viewfinder image also helps. But you give up the floating sensor, Limited lenses, build quality for the price and better auto white balance. I have no experience with Canon.
03-19-2017, 05:25 AM   #41
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QuoteOriginally posted by starbase218 Quote
I've shot jets at airshows with the K-5 and 55-300 and the K-3 with 60-250, with and without TC. I actually got better results with the 55-300. But I think it slso depends on lighting conditions. In general, I find Nikon AF to be more reliable for a similar price. And a stabilized viewfinder image also helps. But you give up the floating sensor, Limited lenses, build quality for the price and better auto white balance. I have no experience with Canon.
Thanks for the feedback! As I mentioned elsewhere, I've no intention of giving up on Pentax in general. I'm just interested in alternatives for photographing planes and birds. I have also used the DA 55-300 with reasonable results, but the image quality with the DA*300 is streets ahead - when it achieves focus. And I have lots of focussed shots from it. But I have also thrown away a lot more which weren't - and I could get a better hit rate with the DA 55-300.
03-19-2017, 06:34 AM   #42
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QuoteOriginally posted by RobG Quote
That's great to know - especially considering that it was an existing third party lens. Certainly the Pentax AF seems to have improved between the K200, K7, K5 and K3. It may be that part of the solution would be to wait for a new APS-C flagship. I haven't seriously considered the K1 simply because most of my lenses are not full frame, and it seems a waste to have a full frame camera running in crop mode.
I should have mentioned that my Canon and Nikon friends don't generally get better results than I do with my K1 with their FF cameras in comparison situations. Both complain that the Pentax colors are much better and the ease of camera operation is superb in comparison. The Nikon shooter does a lot of sports, and I don't, so no comparison there...and he gets excellent results. He does have the best and fastest glass, so I couldn't compare if I wanted too.

QuoteOriginally posted by RobG Quote
Also great to know! When photographing birds, I'm generally walking around, and opportunities are very brief. They seldom give time for the lens to hunt.
The K1 works very nicely with my big slow Bigma...I had maybe 10 seconds overall to get 6 shots of this little girlie Cardinal yesterday afternoon. I had been trying to get a decent shot of her all day but th males kept chasing her and no opportunity arose until late in the day...when she finally lit on the Cheater Branch I got off 6 fast snaps and all but one were fully usable. No hunting, not stalling, the K1 was ready instantly.

FF shots with the Bigma cropped in processing. (Very heavy crops)


Now turn for me...let us see your "beauty side"! (She wants to be a model...I think she will make it!)


QuoteOriginally posted by RobG Quote
I'm amazed that you have an image which has so much detail yet seems to have very low noise despite the high ISO.
Where my previous Pentax bodies would not focus well in low light....or not at all, the K1 does easily. I don't do a lot of low light shooting but it is nice when I do to now be able to get a good and fast AF shot.

It was total darkness when I shot this, using the Tamron 70-200 2.8 and Pentax flash. Focus using the focus assist light was quick and easy and the K1 delivered where my K5IIs would have hunted all night.

No masterpiece...but I did get the shot I wanted. They were lookin' at Charlie Raccoon on the ground eating away at their nightly feed.


To be clear, I never argue with my Canon or Nikon friends over cameras. None of us really care about brands or which is best or worst.....comparisons are incidental when they do occur. If you want to try something else, by all means you should! What I am saying, is that I love my K1, and would bet a hefty amount that others would too...and many more will, no doubt about it!

Try a Canon...try a Nikon....won't hurt, and no one will die...remember....


Best Regards!
03-19-2017, 06:37 AM   #43
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QuoteOriginally posted by biz-engineer Quote
You seem to find the AF of the K1 better than K3's. Well, my experience having extensively used the K3 with DFA150-450 and K1 with DFA150-450 is that the K3 + DFA150-450 had the best AF tracking capability of all, getting between 80% and 100% keepers on birds in flight. With the K1, I get less keepers, the K1 AF seems to have some lag that does not exist on the K3. I shot both K1 and K3 with the same DFA150-450, and I sold the K3 to finance lenses, but I'm considering to buy back a K3 or wait for the next model. The DFA150-450 is very different from other Pentax lenses because it uses some form of step motor that allow the camera / lens to know the AF position, for instance there is no hunting, the lens AF goes in the correct direction immediately. The DFA150-450 AF is fast but not the fastest and speed does not seem to be the limiting factor, but position feedback seem to do the trick for tracking, typically, the DFA150-450 tracks very well what the DFA70-200 can't, surprising since the DFA70-200 is f2.8 we would expect AF to work better but no, the DFA150-450 tracks better. Sharpness wise, the DFA150-450 isn't as sharp as the DA300, but the AF makes all the difference. For having compared the DFA150-450 to alternative lenses, DFA150-450 AF is slower than Canon 100-400 II and slightly slower than Nikon 200-500 but faster than Sigma 150-600s and Tamron 150-600s. Also, the DFA150-450 AF speed is constant from 150mm to 450mm , so is the Canon 100-400 and Nikon 200-500, however, the Tamron and Sigma 150-600s AF slows down as focal length increases, for instance at 600mm the Tamron AF is ridiculously slow, much slower than Pentax AF.
Poor phrasing on my part, but the 'AF is superb' line referred to the 5D Mark IV, not the K-1. I strictly use the K-1 for static subjects (except running water like creeks) like landscapes and closeups, and mostly use manual focus Zeiss and Voigtlander glass. I've only picked up the Pentax 150-450mm at a demo, but it seems quite substantial, almost heavy. I do look forward to renting one pretty soon--I've just got to choose the right events to coordinate with the rental.

I seriously disagree with your comments about the Tamron 150-600mm being slow. What's your context? Over the past two years, I've used it to shoot about 50,000 frames on fast team sports and birds with fine success. Not quite as fast as a Canon 400mm f2.8 of course, but for what it is, the speed and accuracy are good. I've owned both G1 and the newer G2. As I've noted the USB-based AF corrective functionality is excellent for accuracy and speed. Better than the built-in Canon microAF adjustment functions by far.

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03-19-2017, 06:43 AM   #44
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QuoteOriginally posted by Miguel Quote
I seriously disagree with your comments about the Tamron 150-600mm being slow. What's your context?
Owning a DFA 150-450?

QuoteQuote:
I've only picked up the Pentax 150-450mm at a demo, but it seems quite substantial, almost heavy.
Which you don't.

I have to admit though, our fastest lenses are our Tamron lenses, the 90 macro and SP AF 300 ƒ2.8. SO it wouldn't surprise me if the Tamron was as fast. They seem to put value on fast focusing. Pentax's claim to fame would seem to be weather sealing (and compatibility with Pentax bodies.)

Last edited by normhead; 03-19-2017 at 06:49 AM.
03-19-2017, 12:43 PM   #45
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QuoteOriginally posted by Miguel Quote
I seriously disagree with your comments about the Tamron 150-600mm being slow. What's your context?
My friend has a 7D, Tamron 150-600, I had the K3, the DFA150-450 and now the K1. I borrowed the 7D and Tamron 150-600 G1 over a week-end to compare both. The AF on the Tamron was slower than the DFA150-450, and on top of that, AI servo was not always able to lock focus except when using center point because of the f6.3 and the AF points of the 7D aren't all able to cope with less than f5.6.

I use the DFA150-450 with the K1, and the real issue isn't quite the AF, but my ability to keep the moving subject in the AF frame, especially at 450mm, it would be easier if the lens was optically stabilized. If I'm able to keep the subject in the AF frame, the DFA150-450 is fast to focus, and there is a prefocus function, based on what I'm shooting, the AF is instantaneously on the subject.
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