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08-14-2015, 05:33 AM   #286
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QuoteOriginally posted by mecrox Quote
but being able to market your wares as offering top-class AF is pretty darn important.
Absolutely. Capable AF, reliability, handling, optics, price etc - all are important for users, and are important competitive selling points. All should be [continuously] improved in Pentax.

---------- Post added 2015-08-14 at 10:37 PM ----------

QuoteOriginally posted by starbase218 Quote
Anyway, are you saying that you can successfully track small kids running around with e.g. a DA* lens?
I can track cowboys riding bucking bulls randomly around a ring in low-light with a K-3 and a Sigma 70-200. Kids can't be any harder.

08-14-2015, 05:37 AM   #287
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QuoteOriginally posted by mecrox Quote
No complaints here as I don't shoot sports or much wildlife anyway, but being able to market your wares as offering top-class AF is pretty darn important. If you can't then there is no point in offering costly lenses which are predicated on good AF like the 150-400mm. Thus I would expect Pentax to think that continuing to improve their AF was pretty important. AF is a work in progress for every manufacturer and development won't stop for years, if ever. And for as long as Canon insist on overcharging their customers for items like the 7D mk II, Pentax will have a good opportunity to come in below it at an attractive price.
It's not just sports and wildlife. Evening wedding receptions are often very dim venues. You have not control over your background and little light, so you are forced to shoot wide open. People are moving, talking, dancing and lets face it, flash even with a diffuser still sucks. Kids running on a dance floor might not be professional sports fast, but it will take everything a D4 has to keep up in those lighting conditions.
08-14-2015, 05:38 AM   #288
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QuoteOriginally posted by starbase218 Quote
IIRC, AF-C with selective zone (I think covering all the cross-type points but not the linear-type points), center point as initial AF point, probably with SR off and focus hold enabled (don't remember which level).

---------- Post added 08-14-2015 at 02:07 PM ----------



Anyway, are you saying that you can successfully track small kids running around with e.g. a DA* lens?

---------- Post added 08-14-2015 at 02:30 PM ----------



I think Nikon is probably your best bet if you want fast tracking autofocus. The D7200 seems very capable in that respect, and it's about the same price as the K-3 II.

What's more, the user interface of e.g. the D7200 is much better for focus tracking. It is implemented better. With Pentax, you only see the active AF point if it refocuses. With Nikon, you always see what the camera thinks should be the active AF point. So you know immediately if it has lost track of your subject. Even if the actual focus speed and tracking abilities were equal, that alone would win me over if I did a lot of action photography.

e.g. Nikon's 3D tracking AF-C in low light - YouTube
You definitely can track kids running around with a K5 or K3 and a DA *lens. Focus tracking is most useful if there is some predictable movement and little kids don't necessarily have that anyway. For randomly moving subjects, tracking logic is probably less useful.

All that said, if you can't take sharp photos of little kids with most cameras out there on the market now, the problem is not the camera.
08-14-2015, 05:42 AM   #289
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QuoteOriginally posted by rawr Quote
Absolutely. Capable AF, reliability, handling, optics, price etc - all are important for users, and are important competitive selling points. All should be [continuously] improved in Pentax.

---------- Post added 2015-08-14 at 10:37 PM ----------


I can track cowboys riding bucking bulls randomly around a ring in low-light with a K-3 and a Sigma 70-200. Kids can't be any harder.
Yes they can, if they are closer. Before I got to my niece (which was on a birthday party), I was at a Moto GP race. I think the camera did better there as well.

08-14-2015, 05:52 AM   #290
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QuoteOriginally posted by Winder Quote
It's not just sports and wildlife. Evening wedding receptions are often very dim venues. You have not control over your background and little light, so you are forced to shoot wide open. People are moving, talking, dancing and lets face it, flash even with a diffuser still sucks. Kids running on a dance floor might not be professional sports fast, but it will take everything a D4 has to keep up in those lighting conditions.
Yes I agree though for many folks AF is not the overriding issue, and in fact if I moved on from Pentax it would not be because of AF, which is surely "good enough" for my uses, but because they have failed to take advantage of crop format with fast and modern primes which replicate classic focal lengths and haven't done a huge amount with flash performance. A few of those primes would like likely have headed off defectors to Fuji and M43 at the pass, for example. If I stayed with crop format, I would not want second best which is what so many outfits offer these days, alas, and I would guess that in 2-3 years Pentax will be so busy with FF that probably they will be among them.
08-14-2015, 05:56 AM   #291
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QuoteOriginally posted by Rondec Quote
You definitely can track kids running around with a K5 or K3 and a DA *lens. Focus tracking is most useful if there is some predictable movement and little kids don't necessarily have that anyway. For randomly moving subjects, tracking logic is probably less useful.

All that said, if you can't take sharp photos of little kids with most cameras out there on the market now, the problem is not the camera.
Actually, the term "tracking AF" has nothing to do with predicting where the focus should be in the future. Tracking AF means that the light metering sensor is tied into the AF system, so that the AF system can determine if the subject (based on shape, color, etc from the light metering sensor) has moved inside your frame, and if it has, what AF point should be activated to accurately focus on that subject. This way, your subject can be followed across the frame, as demonstrated in the Youtube vid I posted.

Small AF points also help here. Because then there's less of a chance that the active AF point, as determined by the light metering sensor information, focuses on something else. Algorithms may also help here, and settings such as the AF hold option.

I think that you basically need a better predictive algorithm if your lens focuses slower, in order to get the same results, assuming that your subject moves predictably.

Anyway, my niece was on a swing, constantly moving back and forth. I'd say it doesn't get a whole lot more predictable than that. (Or maybe they need to invent swings that only move forward?)
08-14-2015, 06:11 AM - 1 Like   #292
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QuoteOriginally posted by mecrox Quote
Yes I agree though for many folks AF is not the overriding issue, and in fact if I moved on from Pentax it would not be because of AF, which is surely "good enough" for my uses, but because they have failed to take advantage of crop format with fast and modern primes which replicate classic focal lengths and haven't done a huge amount with flash performance. A few of those primes would like likely have headed off defectors to Fuji and M43 at the pass, for example. If I stayed with crop format, I would not want second best which is what so many outfits offer these days, alas, and I would guess that in 2-3 years Pentax will be so busy with FF that probably they will be among them.
What is the price of the Fuji 90mm F/2 compared to the Zeiss Batis 85mm F/1.8? What is the size difference? Zeiss 55mm F/1.8 FE compared to the Fuji 56mm F/1.2? APS-C has to be magnified more to equalize output size, so it requires sharper lenses to achieve the same quality. APS-C requires faster glass and has to be sharper at wider apertures. Look at the Olympus 35-100mm F/2. When it was launched it was larger and more expensive than the Nikon or Canon 70-200mm F/2.8 lenses of the day. For premium glass there is no advantage for APS-C. How much is a Canon or Nikon 85mm F/1.8? Both are great lenses for the money.
08-14-2015, 06:16 AM   #293
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QuoteOriginally posted by starbase218 Quote
With Pentax, you only see the active AF point if it refocuses. With Nikon, you always see what the camera thinks should be the active AF point.
?? Try again with AF-C + 27 point AF with the K-3, AF Hold on medium and focus priority on. The AF is usually able to dynamically follow the target in, out and sideways (within the boundaries of the AF frame).

QuoteOriginally posted by starbase218 Quote
So you know immediately if it has lost track of your subject.
I wish. Having used Nikon 3-D tracking a lot [on a D610], I can say that it isn't the case. The AF points light up and the shutter goes off but very often it's been a mystery exactly what the camera decided to focus on, and you can only find out on image playback. But at least with Nikon, playback in-camera lets you see directly which focus point was used in the shot, so you can adapt your shooting settings fast.


Last edited by rawr; 08-14-2015 at 06:26 AM. Reason: More sage words of wisdom
08-14-2015, 06:26 AM   #294
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QuoteOriginally posted by Winder Quote
What is the price of the Fuji 90mm F/2 compared to the Zeiss Batis 85mm F/1.8? What is the size difference? Zeiss 55mm F/1.8 FE compared to the Fuji 56mm F/1.2? APS-C has to be magnified more to equalize output size, so it requires sharper lenses to achieve the same quality. APS-C requires faster glass and has to be sharper at wider apertures. Look at the Olympus 35-100mm F/2. When it was launched it was larger and more expensive than the Nikon or Canon 70-200mm F/2.8 lenses of the day. For premium glass there is no advantage for APS-C. How much is a Canon or Nikon 85mm F/1.8? Both are great lenses for the money.
So? That could be a CaNikon salesman talking Don't worry about the huge size and weight, just go to the gym. We can recommend a chiropractor. Here, give me your seven thousand dollars right now. The advantage of APS-C is size and in many cases cost but not in all cases. I am fine with that. I am happy with three courses and do not need 16 to feel I have had a gourmet meal, but I do want very good cooking. When I go on vacation I do not take my dog with me in an outsize shoulder bag and lug it round to all the places I visit while it barks and yaps "rich idiot over here" to every passer-by. That squirming bulk is for me what would happen were I to invest in mainstream FF. It's not for me, at least until things out there on planet camera have changed a bit.

Anyway, to get back to the point of the thread, a very good new APS-C camera early next year would be most welcome over here, even more so some great new lenses for it. It will still outsell any FF camera by at least 10-1 and thus, one guesses, provide Pentax with their bread and butter income for the year.

Last edited by mecrox; 08-14-2015 at 06:36 AM.
08-14-2015, 06:59 AM   #295
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QuoteOriginally posted by rawr Quote
I wish. Having used Nikon 3-D tracking a lot [on a D610], I can say that it isn't the case. The AF points light up and the shutter goes off but very often it's been a mystery exactly what the camera decided to focus on, and you can only find out on image playback. But at least with Nikon, playback in-camera lets you see directly which focus point was used in the shot, so you can adapt your shooting settings fast.
I think you may have misunderstood. Indeed you wouldn't know exactly what the camera focused on, but you would know if the light metering sensor is still tracking your subject, right? Because you can always tell if the active AF point is still over the subject. Doesn't the entire tracking system provide more feedback that way?

I am curious though: what lenses did you use with the D610, and what is your general impression of AF tracking compared to Pentax? Also, what lenses do you use on Pentax?
08-14-2015, 07:08 AM   #296
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QuoteOriginally posted by starbase218 Quote
Anyway, are you saying that you can successfully track small kids running around with e.g. a DA* lens?
Depending on kid, how actively it likes jumping around, distance, (equivalent) aperture and how much of the frame it fills, you'll find that no camera can track it (maybe except some industrial set ups with infra red laser-based AF).

That's just th current state of the art in consumer camera business.

And the reason why AF still is a discriminative factor between vendors, camera models and lenses. A fast focussing, shallow depth of field lens is an expensive thing to start with. Pentax' DFA* 70-200/2.8 hopefully will be the first of its kind from Pentax.

Mirrorless most of the time gets away with it by avoiding the difficult situations, i.e., preferring a wide angle lens with slow equivalent aperture (like F4 on APSC or F2.8 on FT). That's what I call "action camera" set up and true, in this set up, AF is not an issue.
08-14-2015, 07:38 AM   #297
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QuoteOriginally posted by starbase218 Quote
what lenses did you use with the D610, and what is your general impression of AF tracking compared to Pentax? Also, what lenses do you use on Pentax?
The D610 has AF that is very competent, and in the field the tracking can be very 'sticky', perhaps due to the extra AF points over a K-3. However it does take some trial and error to get the AF-C tracking in any mode to work as you want it. Even a Nikon will often decide to focus on the railing behind the bull, instead of the bull-rider, despite your best efforts to steer the AF over the colourful jacket of the rider. And in low-light the contrast decline generally means the AF in all D610 modes does lose confidence, in a manner that hardly troubles the K-3. Maybe the D7200 and D750 would be better there.

There are also often lots of other issues that get in the way of decent AF on either camera of course - like lens flare from stadium lighting, dust flying up all over the place etc.

For outdoor events with the D610 it's mainly been the Nikon 70-200 f2.8 VR1. For K-5 and then K-3 it's been the Sigma 70-200 f2.8 HSM II. Both lenses are OK performers, but are one generation removed from the current models.
08-14-2015, 07:42 AM   #298
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QuoteOriginally posted by falconeye Quote
Depending on kid, how actively it likes jumping around, distance, (equivalent) aperture and how much of the frame it fills, you'll find that no camera can track it (maybe except some industrial set ups with infra red laser-based AF).

That's just th current state of the art in consumer camera business.
You're probably right, but that does mean you can't really derive anything meaningful from anecdotal statements like the ones posted here.

QuoteOriginally posted by falconeye Quote
And the reason why AF still is a discriminative factor between vendors, camera models and lenses. A fast focussing, shallow depth of field lens is an expensive thing to start with. Pentax' DFA* 70-200/2.8 hopefully will be the first of its kind from Pentax.
There's one more thing that may not help Pentax when it comes to AF tracking with longer lenses, and that is the fact that no Pentax K-mount lens has built-in stabilisation. This means that both the AF sensor and the light meter see an unstabilised image. I'd imagine this could lead to less reliable AF tracking, and AF performance in general.

(yup, still playing devil's advocate )

QuoteOriginally posted by falconeye Quote
Mirrorless most of the time gets away with it by avoiding the difficult situations, i.e., preferring a wide angle lens with slow equivalent aperture (like F4 on APSC or F2.8 on FT). That's what I call "action camera" set up and true, in this set up, AF is not an issue.
This does remind me of one shot I took of my niece, with the 16-50 zoomed out to 16mm, to capture not only her, but the swing and the sky behind her too. It wasn't perfect (focus was still of a bit), but I liked it a lot.

---------- Post added 08-14-2015 at 04:51 PM ----------

QuoteOriginally posted by rawr Quote
The D610 has AF that is very competent, and in the field the tracking can be very 'sticky', perhaps due to the extra AF points over a K-3. However it does take some trial and error to get the AF-C tracking in any mode to work as you want it. Even a Nikon will often decide to focus on the railing behind the bull, instead of the bull-rider, despite your best efforts to steer the AF over the colourful jacket of the rider.
I'd imagine that would be no different between Pentax and Nikon, as it's just how AF sensors work. The job of the tracking mechanism is to select the right AF point, but there's probably not much difference from there on, apart from Pentax's AF sensor not seeing a stabilised image (assuming the Sigma doesn't have OS).

QuoteOriginally posted by rawr Quote
And in low-light the contrast decline generally means the AF in all D610 modes does lose confidence, in a manner that hardly troubles the K-3. Maybe the D7200 and D750 would be better there.
Interesting. Thanks.

QuoteOriginally posted by rawr Quote
There are also often lots of other issues that get in the way of decent AF on either camera of course - like lens flare from stadium lighting, dust flying up all over the place etc.
Or a fence that's between you and MotoGP bikes.

Last edited by starbase218; 08-14-2015 at 07:53 AM.
08-14-2015, 08:04 AM   #299
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QuoteOriginally posted by starbase218 Quote
Or a fence that's between you and MotoGP bikes.
Get a media pass

98 - and smiles all round - North Coast Road Racers on Flickr


91 knee down - North Coast Road Racers on Flickr
08-14-2015, 08:24 AM   #300
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QuoteOriginally posted by rawr Quote
Get a media pass
Yeah, I know. That's why I didn't want to point to my misfocused bike shots. That's partially user error and I know it.

edit: nice shots btw.

Last edited by starbase218; 08-14-2015 at 08:32 AM.
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