Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-12-2015, 11:16 AM   #751
Site Supporter
Cynog Ap Brychan's Avatar

Join Date: Sep 2012
Location: Gloucester
Photos: Gallery
Posts: 1,092
QuoteOriginally posted by Paul the Sunman Quote
Is anyone really only getting 67% AF success with the K3?
I haven't counted, but my nippy granddaughter doesn't make it easy on my autofocus. That said, my ratio with the Nikon D810 (which has vg AF) isn't a great deal better.

02-12-2015, 12:02 PM   #752
Pentaxian




Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,843
QuoteOriginally posted by Paul the Sunman Quote
Is anyone really only getting 67% AF success with the K3?
AF test results are highly dependent on the subject, the camera AF settings, the lens, and the light. I've done some challenging sports shooting [night-time rodeo] with almost the same rig as the PentaxForums test - a D610 and a Nikon 70-200 f2.8 - and the keeper rate was certainly much less than 96%.
02-12-2015, 12:22 PM   #753
Pentaxian
philbaum's Avatar

Join Date: Oct 2007
Location: Port Townsend, Washington State, USA
Posts: 3,659
QuoteOriginally posted by rawr Quote
AF test results are highly dependent on the subject, the camera AF settings, the lens, and the light. I've done some challenging sports shooting [night-time rodeo] with almost the same rig as the PentaxForums test - a D610 and a Nikon 70-200 f2.8 - and the keeper rate was certainly much less than 96%.
Thats been my experience as well. I'll take 400 rehearsal pics of actors and have over 95 percent be sharp. the main reason for not using pics is eyes closed, head turned the wrong way, etc. Love the K3 and K5 for that matter (except lo light on the K5)

My first buy was a K10 and a Tamron 18-250 and i had this naive view that SR was going to make all my pictures sharp. Then i slapped the combo on a tripod and realized that i was the resp. party for all of my fuzzy pics.

Use a shutter speed thats 2 to 5 times the FL and your pics will be nice and sharp. For a 250 FL, that would require a min. of 1/500s at 2XFL.

SR also needs a little bit to time to settle, so if one is snap-shooting pics - just turn off the dang SR and rely on shutter speed thumb rule.

If one is shooting humans, dogs or any moving subject. SR does not help the moving subject at all. 1/100 to 1/250 will help those people pics to be sharp.
02-12-2015, 12:27 PM - 2 Likes   #754
Pentaxian




Join Date: Jan 2011
Location: New York
Posts: 3,311
QuoteOriginally posted by JPT Quote
I remember seeing a programme on TV where they were having various things cut in half using some kind of high-speed saw, including quite delicate things. They showed a workshop where you could bring anything in to be cut in half for 5,000 yen.
I'll break your stuff for half that price

02-12-2015, 12:48 PM   #755
Pentaxian




Join Date: Jun 2009
Location: GMT +10
Photos: Albums
Posts: 10,843
QuoteOriginally posted by philbaum Quote
Love the K3 and K5 for that matter
One of the reasons the D610 would struggle was low-light and poor contrast. The K-3 AF isn't as troubled by that as much as the D610 is.
02-12-2015, 08:08 PM   #756
Veteran Member
JibbaJab's Avatar

Join Date: Apr 2013
Location: Southern California
Posts: 351
I like it, but why aren't they showing where they're going to place the big fat Ricoh logo?
02-12-2015, 10:12 PM - 1 Like   #757
Senior Member




Join Date: Sep 2014
Posts: 128
QuoteOriginally posted by JibbaJab Quote
I like it, but why aren't they showing where they're going to place the big fat Ricoh logo?
That's cause this time they're gonna condition us subliminally by etching it onto the mirror. Ricoh learns.
02-12-2015, 10:14 PM - 1 Like   #758
Veteran Member




Join Date: Jun 2011
Location: Utah
Posts: 343
I hope that the mock-up of the flippy screen isn't set in stone yet. One of the K-S2's selling points is that the screen is embedded in the shell, rather than protruding from the body and affecting "nose space". The mock-up shows a viewfinder port which is, instead, flush with the screen.

02-13-2015, 12:03 AM   #759
Pentaxian




Join Date: Oct 2010
Photos: Gallery | Albums
Posts: 2,762
IMO saying that K-3 AF system is not good enough is not correct. It is light years ahead of K-7. I can nail shots in dim room even with my DA*55. No problem. And if you think that they are not going to fine tune it for new model, that is silly too. It is going to be really well polished. As anyone can see they are taking their time. It does not have to be the best. But just as good as rest of them. And it will be. As K-3 is, if you can use it properly. And let's see these tests with that new 70-200...I'm sure that it will be fast.
02-13-2015, 09:44 AM   #760
Pentaxian
philbaum's Avatar

Join Date: Oct 2007
Location: Port Townsend, Washington State, USA
Posts: 3,659
QuoteOriginally posted by repaap Quote
IMO saying that K-3 AF system is not good enough is not correct. It is light years ahead of K-7. I can nail shots in dim room even with my DA*55. No problem. And if you think that they are not going to fine tune it for new model, that is silly too. It is going to be really well polished. As anyone can see they are taking their time. It does not have to be the best. But just as good as rest of them. And it will be. As K-3 is, if you can use it properly. And let's see these tests with that new 70-200...I'm sure that it will be fast.
In static low light focusing, i believe the K3 is better than most cameras out there. When i've tried AF tracking, it works fine when tracking flying birds at a distance, but up close, the K3 fails and other cameras would fail at some point as well. I don't believe there's been any hard repeatable testing of the K3 or any camera's tracking ability - its mostly annecdotal or limited comparisons for a certain situation.

If a lens is going to quickly follow the focusing commands from the camera body, the internal lens adjusting mechanism has to be lightweight and the lens motor must be very strong. With the new FF lenses and the new FF body, Pentax has a chance to improve the AF tracking of its flagshift camera.

For static low light focusing, the K3 will beat its Nikon and Canon APS counterparts hands down. I can't believe the K3 is as cheap as it is today - between $600 to 700 i believe. What a bargain.
02-13-2015, 10:31 AM   #761
Pentaxian




Join Date: Oct 2010
Photos: Gallery | Albums
Posts: 2,762
Exactly!
02-13-2015, 10:39 AM   #762
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,771
QuoteOriginally posted by philbaum Quote
In static low light focusing, i believe the K3 is better than most cameras out there. When i've tried AF tracking, it works fine when tracking flying birds at a distance, but up close, the K3 fails and other cameras would fail at some point as well.
+1 on this. I used to take 3 or even 4 shots with the k-5 to make sure I got a good solid keeper. I continued to do so with the k-3 until I realized I had NO badly focused shots. I was still taking three, but could not tell the difference. For static shots I honestly do not know how it could get any better. Tracking is another issue, though. I don't do much of it and I'm sure my inexperience there is part of the problem but I could not get good results with birds in flight. But there are lots of options there that I have not looked at. And since 98% of my shooting is static objects or fixed landscape on tripods, the k-3 is just fine.

One thing that I would like to see improved is the spread of the points. On the tripod it would be very nice to have some AF points closer to the edge of the image. Might help with tracking too I suppose.
02-13-2015, 01:03 PM   #763
Site Supporter




Join Date: Jul 2011
Photos: Gallery | Albums
Posts: 962
QuoteOriginally posted by philbaum Quote
In static low light focusing, i believe the K3 is better than most cameras out there. When i've tried AF tracking, it works fine when tracking flying birds at a distance, but up close, the K3 fails and other cameras would fail at some point as well. I don't believe there's been any hard repeatable testing of the K3 or any camera's tracking ability - its mostly annecdotal or limited comparisons for a certain situation.

If a lens is going to quickly follow the focusing commands from the camera body, the internal lens adjusting mechanism has to be lightweight and the lens motor must be very strong. With the new FF lenses and the new FF body, Pentax has a chance to improve the AF tracking of its flagshift camera.

For static low light focusing, the K3 will beat its Nikon and Canon APS counterparts hands down. I can't believe the K3 is as cheap as it is today - between $600 to 700 i believe. What a bargain.

You touched on, but didn't really hit on a point I also wanted to try and make...


And that is...I think the speed of the lens effects the camera's ability to do continuous AF tracking well, because even though it is the camera CPU & software doing the tracking by reading off the sensor or Fresnel, it only has what it gets through
the lens glass as "data" to work with.


So for example, if the little crumb cruncher is running at you fast, and you have perfect focus on the first step, but the lens motor doesn't re-focus fast enough on the second step towards you, then the computer now has a less sharp, lower contrast image in its field of view and if it doesn't reacquire a high contrast sharp image in the next focus step, then by the third step towards you it will be so soft that the acquisition will be lost and it will be too late and have no chance of catching up then it starts hunting. At least this is what I see in practice.


To drive my point home, what I guess I'm trying to say is that perhaps newer faster lenses will make the existing CAF work better, and the problem might not be with the CAF software or hardware in the camera. The speed of the screw drive in the camera of course could effect CAF as well, but I've always thought screw drive had already pretty much reached it's limit of performance and there is nothing more to be really gained there and that any real improvement in AF speed will have to come from in-lens motor electrickery.


Eric
02-13-2015, 07:26 PM   #764
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,771
Will be very interesting to see AF speed with new 70-200 on the k-3.

I also suspect the lenses are holding back the camera.
02-14-2015, 06:52 AM   #765
Senior Member




Join Date: Feb 2014
Location: Western Australia
Photos: Albums
Posts: 173
QuoteOriginally posted by lytrytyr Quote
Thank you!
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!
645z, adam, answer, blah, camera, couple of weeks, cp, date, dont, information, jan, job, kenneth, market, nancy, nikon, pentax, pentax news, pentax rumors, people, pm, post, relationship, ricoh, sad, sensor, thanks, time, where is the q5?!
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Z countdown JPT Pentax News and Rumors 289 04-14-2014 12:38 PM
7-day countdown to Borneo frogoutofwater General Talk 4 02-20-2014 08:32 AM
Countdown to the Upcoming new Pentax products. i83N Pentax News and Rumors 21 03-25-2013 07:47 AM
Countdown... Wildnsyko Photographic Technique 2 01-12-2009 08:02 AM
2006/07 countdown - Montreal godwine Post Your Photos! 5 07-12-2007 07:45 PM



All times are GMT -7. The time now is 06:06 PM. | 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