Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-23-2016, 03:30 PM   #31
Pentaxian




Join Date: Jan 2015
Location: mid nth coast,nsw
Photos: Gallery
Posts: 1,699
QuoteOriginally posted by nomadkng Quote
I know of at least one d810 owner who's jealous as hell i paid 1/4 what he did and i can match his output pixel for pixel.
Did he get ripped off? or did he get a bunch of lenses too?


I'm seeing the D810 for $200(150 US) more in Australia....the D810A is over 1000 aussie dollars more.

08-23-2016, 03:47 PM   #32
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,612
QuoteOriginally posted by nomadkng Quote
I'm not real fond of the K1 multi-point algorithm. Wasn't fond of the K20 or K5iis or K3 either. But then again, most Nikon shooters i hang out with don't use multi-point either, they rely on their own tracking skills to keep the center point dot on target.
Glad to see someone else point out what happens in the field regardless of what brand is being shot. I will sometimes use multi-point on my K-3 and often enough am amazed, but never when focus is important.

QuoteOriginally posted by nomadkng Quote
When shooting burst mode, the results are entirely dependent are YOUR ability to track a subject during the frame blackout (shutter up) because the AF sensor is in the dark as well. Nikon does this better than any other manufacturer, but the weakest link is STILL the photog. Why do you think Nikon went to 99+ points, because the average person is horrible at tracking. How good are you? Go to a skeet range with a 20 gauge and find out.... it's the exact same technique!
Man...I wish I had written that and am glad someone finally did. On a burst, Nikon does an intelligent mix of predictive analysis (not the same as tracking...not even close) along with rapid re-acquisition of focus on the presumptive subject. That is incredibly impressive and not something I would expect every competitor to match.

QuoteOriginally posted by nomadkng Quote
Instead of "I'm happy with the K1 AF-C." How about "Here's my pic and here's how I did it. You can too."?
Thanks for adding this part. AF is a tool and with all tools, technique is required at some level to optimize performance. Folk tend to think that their camera AF is holding them back in some way, yet I am old enough to know that spectacular in-focus photos of wildlife, birds in flight, field sports, gravity sports, motor sports, and even the occasional wedding were the norm for working professionals in the years before the AF cameras.*

QuoteOriginally posted by nomadkng Quote
Get over your inferiority complex pentax shooters.

Am I 100% thrilled with the K1 AF-C? No. But it's a hell of a lot better than the K3 could ever be.
...and the K-3 AF performance ain't half bad. (Saying that as a current K-3 owner with no money for a K-1. )


Steve

* Manual focus remains my fall-back technique for many sports. I don't do BIF, but I know a few who use manual technique for that challenging genre as well...shooting Canon...
08-23-2016, 07:14 PM   #33
Pentaxian




Join Date: Sep 2008
Location: Phoenix, AZ
Posts: 1,430
QuoteOriginally posted by stevebrot Quote
Thanks for adding this part. AF is a tool and with all tools, technique is required at some level to optimize performance. Folk tend to think that their camera AF is holding them back in some way, yet I am old enough to know that spectacular in-focus photos of wildlife, birds in flight, field sports, gravity sports, motor sports, and even the occasional wedding were the norm for working professionals in the years before the AF cameras.*
My mentor/main shooting buddy spent 8 years working for Sports Illustrated back in the film days. He related this story to me once:

The final stage of his job interview was at an NFL stadium. He was given full credentials and the standard Canon kit with a 2.8 L zoom lens. I forget the focal length, but probably 100-400 or 100-300.

His assignment was to shoot in full MANUAL mode including focus for one half. He was required to shoot nothing but the football during passing and running plays. It was mandated he bring back 100 images (4 rolls of film) in minimum sequences of 5 and all 100! images had to have the football publishing sharp.

THAT is pressure. THAT is talent. I aspire to that level, but doubt I'll ever get there.

It's why he has some pulitzer prizes, and I still have to keep my day job.

Last edited by nomadkng; 08-23-2016 at 07:23 PM.
08-23-2016, 07:32 PM   #34
Loyal Site Supporter
Rupert's Avatar

Join Date: Sep 2006
Location: Texas
Photos: Gallery | Albums
Posts: 24,362
These AF threads and all the bickering back and forth make me glad I am a still subject shooter! I'm plenty happy when I get a stationary subject sharp, which is much easier than ever before with the K1!

Regards!

08-23-2016, 07:51 PM   #35
Site Supporter
micromacro's Avatar

Join Date: Jan 2014
Location: Florida
Posts: 3,015
QuoteOriginally posted by biz-engineer Quote
Usually, Pentax K3 and K1 AF is very bad at tracking slow motion subjects because subject motion give very poor accuracy on predictive af tracking. There is a zone of incompetence of the Pentax K3/K1 AF system and it is slow moving target too slow for AFC but too fast to be snapped for AFS. For really high speed targets, the limit is the lens actuation.
This probably explains why I can't get good in focus ratio for pictures of slow moving subjects.
08-23-2016, 08:24 PM   #36
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,612
QuoteOriginally posted by nomadkng Quote
It's why he has some pulitzer prizes, and I still have to keep my day job.
I am long time friends with a husband-wife team of wildlife shooters who at one time were the foremost photographers of bald eagles and "lower 48" grizzlies...all with manual focus gear packed light (no motordrives and lenses of modest focal length) for the backcountry.


Steve

(...OK, no more thread hijack by me...)
08-24-2016, 01:08 PM   #37
Pentaxian




Join Date: Feb 2015
Photos: Albums
Posts: 3,153
QuoteOriginally posted by stevebrot Quote
Are you making this stuff up? I believe you are stating multiple unsupported assumptions starting with the first phrase.
humm , I'm electrical engineer , telecom engineer, and studied and designed servos, for basic example is the PLL (Phase Locked Loop) where you a low pass filter in the feedback path , and the closed loop dynamic response is the one of a bandpass filter. I assume it is the same for AF dynamic response, including an basic AF servo (AFS) and for the purpose of tracking an outer loop around the primary AFS servo.
08-24-2016, 02:01 PM   #38
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 26,612
QuoteOriginally posted by biz-engineer Quote
I assume it is the same for AF dynamic response, including an basic AF servo (AFS) and for the purpose of tracking an outer loop around the primary AFS servo.
Good enough. I am not an engineer, except by job title at times, but I was able to follow your descriptions and figured you were describing how such a system might be built if indeed that was what it was doing.


Steve

08-24-2016, 04:43 PM   #39
Pentaxian




Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,714
QuoteOriginally posted by biz-engineer Quote
I assume it is the same for AF dynamic response
The K-1/K-3 AF.C uses colour information too for the tracking behaviour, not just contrast. Remember to throw that into the equation as well for your AF.C control loop.

Plus the AF equation needs to include, of course, the AF.C behaviour boundaries established by the 4 AF hold settings. And the boundaries set by the 6 [3 and 3] action priority settings [for first frame, then continuous shooting behaviour].

Last edited by rawr; 08-24-2016 at 04:48 PM.
08-25-2016, 03:24 AM   #40
Pentaxian




Join Date: Oct 2010
Photos: Gallery | Albums
Posts: 2,678
QuoteOriginally posted by rawr Quote
The K-1/K-3 AF.C uses colour information too for the tracking behaviour, not just contrast. Remember to throw that into the equation as well for your AF.C control loop.

Plus the AF equation needs to include, of course, the AF.C behaviour boundaries established by the 4 AF hold settings. And the boundaries set by the 6 [3 and 3] action priority settings [for first frame, then continuous shooting behaviour].
And for what I have noticed, as a owner of K-3 and K-1, RGB sensor is more precise with K-1. With K-3 it did notice color and focused on something which is majority in frame branches were more focused than bird, which was brighter...but with K-1 if you point that focus point to different color target. It remains there and even if you loose it for a moment you can find it again. This is same stuff but engineers have tweaked it in good direction. Now people just has to learn how to make it work for them.
08-27-2016, 03:56 PM - 1 Like   #41
New Member
Sylwester's Avatar

Join Date: Jul 2014
Photos: Albums
Posts: 17
Ok. Time has come.
I have always used AFS to shoot everything. I had K-5 for a long time, and was very satisfied, then I left system cameras and sticked to Panasonic FZ-1000. Was not satisfied, and had no time to take photos (yes, Panasonic stuff left almost untouched). I've bought K-1 about 3 month ago, and again. AFS. AFS shots (no sports at all, which i like). But yesterday. Hey? What is that noise about Pentax AFC? Let's try it.
So, Pentax AFC. I use single shot always, not bursts, because i want to be satisfied with my timing (one shutter moment).
Two links and results:
1st: Woman's soccer 2nd league match in Poland. 30% shots rejected because i was not satisfied with my timing and composition (still a lot to improve skills). All of them are cropped, mostly very strong. AFC accuracy? ~90%
Darbor Boles?awice - Rekord Bielsko-Bia?a, 27.08.2016 r. | www.jaworzynka.info
2nd: Men's soccer 4th league match in Poland. 50% shots rejected because my skills/composition and i went hardcore and took almost all the photos agains the sun (as u can see). All of them are cropped, mostly very strong. AFC accuracy? ~ 80%
MKS Karolina Jaworzyna ?l?ska - GKS Kobierzyce, 27.08.2016 r. | www.jaworzynka.info
Please.... You might ask the lens. Yes. Tamron 70-200 screwdriwer shit. Screwdriwer!
Comparing to K-5, the K-1 AFC is a HUGE HUGE HUGE difference. I wasn't able to use AFC on K-5 at all with Sigma 70-200 HSM, which i have sold (cry). Now i can use AFC on screwdriwer lens with much much much better results.
Now i'm trying to get money to buy Pentax 70-200. Probably it would be no brainer (focus skills).
Pentax K-1 AFC is really good.
PS Sorry for my english. Cheers.
08-27-2016, 04:39 PM   #42
Pentaxian
noelpolar's Avatar

Join Date: Oct 2013
Location: Goolwa, SA
Posts: 3,064
QuoteOriginally posted by Sylwester Quote
Ok. Time has come.
I have always used AFS to shoot everything. I had K-5 for a long time, and was very satisfied, then I left system cameras and sticked to Panasonic FZ-1000. Was not satisfied, and had no time to take photos (yes, Panasonic stuff left almost untouched). I've bought K-1 about 3 month ago, and again. AFS. AFS shots (no sports at all, which i like). But yesterday. Hey? What is that noise about Pentax AFC? Let's try it.
So, Pentax AFC. I use single shot always, not bursts, because i want to be satisfied with my timing (one shutter moment).
Two links and results:
1st: Woman's soccer 2nd league match in Poland. 30% shots rejected because i was not satisfied with my timing and composition (still a lot to improve skills). All of them are cropped, mostly very strong. AFC accuracy? ~90%
Darbor Boles?awice - Rekord Bielsko-Bia?a, 27.08.2016 r. | www.jaworzynka.info
2nd: Men's soccer 4th league match in Poland. 50% shots rejected because my skills/composition and i went hardcore and took almost all the photos agains the sun (as u can see). All of them are cropped, mostly very strong. AFC accuracy? ~ 80%
MKS Karolina Jaworzyna ?l?ska - GKS Kobierzyce, 27.08.2016 r. | www.jaworzynka.info
Please.... You might ask the lens. Yes. Tamron 70-200 screwdriwer shit. Screwdriwer!
Comparing to K-5, the K-1 AFC is a HUGE HUGE HUGE difference. I wasn't able to use AFC on K-5 at all with Sigma 70-200 HSM, which i have sold (cry). Now i can use AFC on screwdriwer lens with much much much better results.
Now i'm trying to get money to buy Pentax 70-200. Probably it would be no brainer (focus skills).
Pentax K-1 AFC is really good.
PS Sorry for my english. Cheers.
Get yourself a Sigma OS HSM..... last model made.... love mine and way cheaper.

I don't understand why sigma wouldn't do another run of these..... as they are still current in other mounts..... even if they were priced at a premium....given how OTT the DFA is priced.

Last edited by noelpolar; 08-27-2016 at 11:11 PM.
08-27-2016, 04:45 PM   #43
New Member
Sylwester's Avatar

Join Date: Jul 2014
Photos: Albums
Posts: 17
QuoteOriginally posted by noelpolar Quote
Get yourself a Sigma OS HSM
That was the exact version that i have sold about 2 years ago (so I cry). EX DG OS HSM 2.8 (cry a lot).
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
af-c, da*, dslr, flickr, full frame, full-frame, k-1, k1, pentax k-1, shots, trees
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Japanese blogger tests K-3 II AF.C performance against K-3: Measurable improvement bwDraco Pentax K-3 17 05-01-2016 10:04 AM
K-3's AF.C with Focus priority. skyer Pentax K-3 18 12-11-2014 05:44 PM
Pentax K-x: focus confirmation in AF-S, AF-C, not AF-A manteiv Pentax DSLR Discussion 24 12-10-2010 07:25 PM
For Sale - Sold: s-m-c takumar 85mm/f1.9, s-m-c 35mm/f2, smc-k 50 1.2 and more zhha Sold Items 14 10-03-2010 05:24 PM
K-7 and AF-C performance? Clem Nichols Pentax DSLR Discussion 16 07-20-2009 12:50 AM



All times are GMT -7. The time now is 03:11 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top