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04-08-2015, 10:52 AM   #16
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QuoteOriginally posted by normhead Quote
Did you really want to know or were you just being sarcastic?
Both :-)

04-08-2015, 12:53 PM   #17
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I've found the AF performance to be essentially the same on the K-5IIs and the K-3. Though it might seem that with more than twice the number of AF sensor areas (27 as opposed to 11) that the center AF sensor area must be considerably smaller is just not true in my experience. I always map the center AF sensor area on any new camera, and I was a bit disappointed to find that the K-3's was not really significantly smaller (and therefore much more discreet) than that of the K-5IIs (nor the K-5, or any other 11 point Pentax SAFOX version). The center AF sensor area is still virtually the same as the central ( ) indicator in the VF. I have learned to live with this, and can get all of my Pentax bodies to AF reliably by adapting to the Pentax system and learning how to use it to my best advantage.

biz-enginneer's comment "AF is accurate if the image content falling into the AF center point sensor area has enough horizontal or vertical detail/contrast to focus on." is a good one to remember, though the contrast edge orientation (either horizontal of vertical) is not nearly as important in hand held shooting since it's easy enough to tilt the camera for focusing, then return to normal orientation to take the shot.

The K-3 has a lot more options in AF-C, but I rarely shoot moving subjects, so there are many who can advise about tweaking the AF settings better than I can.

For me, the most important thing to do is concentrate on what I see in the VF, and visually confirm critical AF. This has become more difficult with time because my vision varies quite a bit over the course of the day. I pay close attention to the diopter setting of my VF and adjust it as needed to get the clearest view. I sometimes have to re-actuate AF a number of times until the subject "pops" in the VF, then I take the shot.

Scott
04-08-2015, 01:15 PM   #18
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QuoteOriginally posted by Shanti Quote
Maybe been answered somewhere..but is the DA*300 more accurate in focus than the K5II? when I get a good shot in focus with the DA*300 its perfect,but many misses,even though AF is locked on. I only use center point AF--mostly birds & BIF. larger animals have a lot more keepers
IME, the center point on the K-3 is smaller than the 11-point bodies, and noticeably more accurate for birds in trees.

You say you're using center point AF for birds in flight. If you only use center point, you are not tracking the bird. You need to use center point with expansion. For birds I find I need 27-point because they're too hard to keep in the center of the frame. For sports I use center point expandable to 9 points. In conjunction with this, you want to use AF Hold. I like the Medium setting. AF-C is a given, and turn off SR.

---------- Post added 2015-04-08 at 16:21 ----------

QuoteOriginally posted by twitch Quote
This was exactly my experience too. Terrible accuracy from the K-3 with seemingly daily changes required in AF adjustment amounts. No such problem with my K-5.
My K-5 had severe front-focus in tungsten light so I sent it back with no request for a replacement. I've had stellar performance from the K-3, but I've had to return my DA*300 twice. AF was horribly slow, so they replaced the focus motor. A few months later the focus moved normally, but would not lock on the subject (hexagon would not stop blinking). They replaced the AF Module, and all has been fine for a few months.

Last edited by audiobomber; 04-08-2015 at 01:23 PM.
04-08-2015, 01:34 PM   #19
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QuoteOriginally posted by twitch Quote
Terrible accuracy from the K-3 with seemingly daily changes required in AF adjustment amounts.
If you are doing frequent changes to your AF fine adjustment, you might want to consider your methodology or sending your camera in for service. Dialing in your AF is a lot like dialing in the sight/scope on a rifle. Getting it right takes some work, but once done you should not have to do it again.


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04-08-2015, 02:00 PM   #20
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QuoteOriginally posted by audiobomber Quote
IME, the center point on the K-3 is smaller than the 11-point bodies, and noticeably more accurate for birds in trees.

You say you're using center point AF for birds in flight. If you only use center point, you are not tracking the bird. You need to use center point with expansion. For birds I find I need 27-point because they're too hard to keep in the center of the frame. For sports I use center point expandable to 9 points. In conjunction with this, you want to use AF Hold. I like the Medium setting. AF-C is a given, and turn off SR.

---------- Post added 2015-04-08 at 16:21 ----------



My K-5 had severe front-focus in tungsten light so I sent it back with no request for a replacement. I've had stellar performance from the K-3, but I've had to return my DA*300 twice. AF was horribly slow, so they replaced the focus motor. A few months later the focus moved normally, but would not lock on the subject (hexagon would not stop blinking). They replaced the AF Module, and all has been fine for a few months.
Ok I try again with 11 points,had tried both & had more luck tracking with 1,also using MF override
I had to send my da300 in to get the front focus fixed(beyond the camera settings) it helped but the hex still blinks like mad,even when I see its in focus? maybe need to send it in again
And another here said the DA300 was the worst lens for AF? I know my DA70 is very quick & accurate..so maybe using the DA300 + HD1.4 is not the best solution for birds. The new DFA 150-450 may have fixed all the AF issues..so far the shots I've seen are sharp & good contrast..but no info yet on AF_C performance...

---------- Post added 04-08-15 at 11:08 PM ----------

QuoteOriginally posted by audiobomber Quote
IME, the center point on the K-3 is smaller than the 11-point bodies, and noticeably more accurate for birds in trees.

You say you're using center point AF for birds in flight. If you only use center point, you are not tracking the bird. You need to use center point with expansion. For birds I find I need 27-point because they're too hard to keep in the center of the frame. For sports I use center point expandable to 9 points. In conjunction with this, you want to use AF Hold. I like the Medium setting. AF-C is a given, and turn off SR.

---------- Post added 2015-04-08 at 16:21 ----------

My K-5 had severe front-focus in tungsten light so I sent it back with no request for a replacement. I've had stellar performance from the K-3, but I've had to return my DA*300 twice. AF was horribly slow, so they replaced the focus motor. A few months later the focus moved normally, but would not lock on the subject (hexagon would not stop blinking). They replaced the AF Module, and all has been fine for a few months.
where is AF hold on the K5II??

---------- Post added 04-08-15 at 11:17 PM ----------

QuoteOriginally posted by Adam Quote
To answer your question, no, not really. Both the K-5 IIs and the K-3 have the same great accuracy and low light capabilities, and the extra points won't make much of a difference if you're sticking with the center point. The K-3 has a faster screwdrive motor but obviously this wouldn't affect the performance of your 300mm.

I doubt the FF will have 50 megapixels, since there isn't really a sensor on the market Pentax would use (Canon probably wouldn't sell theirs).
Hi the Sony A9 will have at least 50MP from what all the rumors say,and Sony sells to Pentax..so we may be surprised
04-08-2015, 03:18 PM   #21
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QuoteOriginally posted by Shanti Quote
Hi the Sony A9 will have at least 50MP from what all the rumors say,and Sony sells to Pentax..so we may be surprised
When Hell freezes over and that Rand guy gets the nomination.


Steve
04-08-2015, 05:29 PM   #22
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QuoteOriginally posted by stevebrot Quote
When Hell freezes over and that Rand guy gets the nomination.


Steve
Pentax is NO threat to Sony..so why not..can't let Canon get all the glory
& be careful what you wish..Tea Party is really scary!!!

04-08-2015, 06:20 PM   #23
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QuoteOriginally posted by Shanti Quote
where is AF hold on the K5II??
Sorry, there is none. I thought you had a K-3.

Your DA*300 focus confirmation problem sounds like what mine was doing before they replaced the AF module.

I've shot hundreds of well focussed BIF shots with the K-3 and DA*300, with and without the HD 1.4X TC. It is a very capable rig.
04-09-2015, 01:21 AM   #24
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QuoteOriginally posted by normhead Quote
When I go out shooting birds... A-400 or DA*60-250 + 1.4 TC on the K-3, DA 18-135 on the K-5. With the A-400, all you get is s centre point. AF priority slows you down. You just have to remember to partially depress to refocus if your animal changes position. I almost always use AFs, with the exception maybe of birds in flight, if I have time to switch, and I remember, I might go to AF-c.
AF-s and expanding AF points is pointless ... Af-s = single shot AF i.e af point is selected and acted on
Expanding AF = hand-off AF control to adjacent sensor as target moves within frame during focusing

So expanding AF and AF-s = slower AF as camera still operates as single point AF but has to assess adjacent points

With expanding AF you need to be using AF-c to get any real benefit.

---------- Post added 09-04-15 at 09:32 AM ----------

QuoteOriginally posted by Shanti Quote
And another here said the DA300 was the worst lens for AF? I know my DA70 is very quick & accurate..so maybe using the DA300 + HD1.4 is not the best solution for birds. The new DFA 150-450 may have fixed all the AF issues..so far the shots I've seen are sharp & good contrast..but no info yet on AF_C performance...[COLOR="Silver"]
I wonder how many are using faulty lens or cameras
This shows a working da*300 AF end to end with the HD1.4 attached


Last edited by awaldram; 04-09-2015 at 01:33 AM.
04-09-2015, 05:00 AM   #25
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QuoteOriginally posted by awaldram Quote
I wonder how many are using faulty lens or cameras
Me too, especially since I have had my DA*300 go off twice. That video shows that SDM on the 300mm is fast, and that has been my experience. Definitely quicker to focus than the Sigma 150-500mm OS HSM I owned for a few weeks.

The K-5 is well known for wonky AF. The K-5 II is certainly better, but does not have the sophisticated tracking controls or 27 points of the K-3. Then there's technique. Shooting BIF requires practice, and settings that help, not hinder the camera.

Last edited by audiobomber; 04-09-2015 at 12:45 PM.
04-09-2015, 12:24 PM   #26
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While I understand what Adam is saying regarding the specific SDM lens and sticking with the center point for focus, the possibilities of getting better BiF with the K-3 in certain instances are pretty apparent, especially when you look at the comparative test results done in the review here. Once you move off Center only for BiF, the advantages are especially apparent. The K-3 gives you more FPS (more opportunities to nail the shot), tighter AF spacing if you try Auto (and 9 focus points vs. 5), 3 better cross-focus points in the central area (as opposed to 1), and a considerably better tracking record in lower light. If you have a screw drive lens, the K-3 will be quicker.

In great light - if you are sure you will be able to get the shot using center focus - and rely only on a lens-drive system, then I suppose the focus systems will be equal. That's a lot of caveats, though.
04-09-2015, 05:09 PM   #27
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QuoteOriginally posted by audiobomber Quote
Me too, especially since I have had my DA*300 go off twice. That video shows that SDM on the 300mm is fast, and that has been my experience. Definitely quicker to focus than the Sigma 150-500mm OS HSM I owned for a few weeks.

The K-5 is well known for wonky AF. The K-5 II is certainly better, but does not have the sophisticated tracking controls or 27 points of the K-3. Then there's technique. Shooting BIF requires practice, and settings that help, not hinder the camera.
Its been almost 2 yrs since my DA300 was serviced,so wonder if it needs a new focus module now? the service man said it was fine then--only 2.5 yrs old ..seems a short time for the motor to live

---------- Post added 04-10-15 at 02:13 AM ----------

QuoteOriginally posted by audiobomber Quote
Sorry, there is none. I thought you had a K-3.

Your DA*300 focus confirmation problem sounds like what mine was doing before they replaced the AF module.

I've shot hundreds of well focussed BIF shots with the K-3 and DA*300, with and without the HD 1.4X TC. It is a very capable rig.
how old was your lens when the AF module was replaced? hate to give up on it as contrast & resolution are really good..just wish I could try a K3 somewhere...as no one has Pentax where I am
04-09-2015, 06:08 PM   #28
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QuoteOriginally posted by Shanti Quote
how old was your lens when the AF module was replaced?
My DA*300 failed twice during the two-year warranty period.
04-10-2015, 06:31 PM   #29
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QuoteOriginally posted by audiobomber Quote
My DA*300 failed twice during the two-year warranty period.
Just found out Pentax service in Sweden gives 3yr warranty on the SDM,so I send mine in soon..they say main board may need changing as well..
he also said the focus motors never run near max speed,as must be compatible with all cameras...
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