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01-28-2012, 12:47 AM   #136
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QuoteOriginally posted by cbope Quote
Hmm... I don't get that with my K-5. If I focus on something in the room, and then move the camera by panning or even rotating, the hand symbol in the VF stays on. Even if I shake the camera quite a lot, it stays on as long as I keep the shutter button half pressed. It does take a small amount of time to stabilize before it lights after pressing the shutter button halfway, I'd guess from a few hundred milliseconds up to a second depending on available light. But once it comes on it stays on until I release the shutter button or take a shot.

Edit: I have the latest 1.12 firmware.

You're right, i last observed the icon going out with v1.11, but its been fixed with v1.12 apparently, as i don't see it that problem any longer. Hmmm...

01-28-2012, 05:20 AM - 1 Like   #137
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QuoteOriginally posted by philbaum Quote
You're right, i last observed the icon going out with v1.11, but its been fixed with v1.12 apparently, as i don't see it that problem any longer. Hmmm...
No, the behavior is the same as before. If you press and hold the shutter button the SR icon stays lit no matter what you do, fooling the user that it is ready at all times. But if you only tap the shutter button the SR icon will show the true state, and thus go out if you move around too much. A clear bug IMO.

Systems with the SR in the lenses doesn't have this "problem" as the user clearly sees in the viewfinder that the SR system isn't ready if they move the camera. The picture in the viewfinder is floating around and one needs to wait for it to stabilize, it's very obvious that one have to wait. We only have the icon to watch, and it's fooling us.

Last edited by Gimbal; 01-28-2012 at 05:27 AM.
01-28-2012, 06:15 AM - 1 Like   #138
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I am going to try to be nicer. Sorry about the woman remarks.
I have had the k-5 since it came out. Sent it in to Pentax Japan for calibration and rebuild. It came back flawless. AF was spot on on my lenses to a point I thought I was in heaven. Until I experience the issues explained here by Christene. Missed focus? I bought a Canon 7D because I was not satisfied with the AF performance of the K-5. I've been shooting side by side with these two cameras daily for about a year now. It is really very simple IMHO. Canon will not lock and forces you to find a good target for AF to lock. It has helped me with the K-5 tremendously. I consider the AF module in the K-5 to rival that of the Canon 7D. But the difference is in the algorithms that control the AF to lock or not to lock. It is a simple matter of who has the money to invest in the engineering and R&D to perfect these algorithms ( and modules ). It is obviously a very difficult task that even the best engineers have problems with. And even with Canon and Nikon they have reached a compromise as to where to cut it off. It must be a daunting task. I will say that after buying a Canon 7D my experience with the k5 makes allot of scene. And hence my keeper rate with the K-5 has skyrocketed. It really is unbelievable.
That is my experience with the AF system with Pentax and Canon so far. Buying a Canon was the best thing I could of ever done. It helped me be a better Pentax shooter and understand the daunting task of AF systems in general.

Last edited by garyk; 01-28-2012 at 06:27 AM.
01-28-2012, 08:28 AM   #139
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The only Cannon Ive ever owned was the EOS3 35mm film camera. The focussing was always spot on and never missed a beat. My first digital camera was the Olympus E1 which if i remember correctly had only 3 auto points and was notably slower, but still always locked etc. The Nikon D300..... never misses a beat. Basicly, Ive had cameras that may have been a tad slow, or even hunt on the odd occassion.
The pentax K5 has without question the worst focussing Ive yet to experience and is not even capable of competeing with cameras from four generations ago.
You can live with slow focus etc, but, when it achieves focus and you take the shot thinking you have the shot in the bag only to find that the camera had
accepted that it was in focus and then to later find that your pic is a total blur is simply unaceptable.
Thats the kind of performance you might expect of a 70 compact camera, not an expensive Top end camera from the pentax Ilk.
This day and age, reliable autofocus is something we tend to take for granted.


Last edited by westmill; 01-28-2012 at 08:47 AM. Reason: more thoughts
01-28-2012, 11:33 AM   #140
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QuoteOriginally posted by westmill Quote
The only Cannon Ive ever owned was the EOS3 35mm film camera. The focussing was always spot on and never missed a beat. My first digital camera was the Olympus E1 which if i remember correctly had only 3 auto points and was notably slower, but still always locked etc. The Nikon D300..... never misses a beat. Basicly, Ive had cameras that may have been a tad slow, or even hunt on the odd occassion.
The pentax K5 has without question the worst focussing Ive yet to experience and is not even capable of competeing with cameras from four generations ago.
You can live with slow focus etc, but, when it achieves focus and you take the shot thinking you have the shot in the bag only to find that the camera had
accepted that it was in focus and then to later find that your pic is a total blur is simply unaceptable.
Thats the kind of performance you might expect of a 70 compact camera, not an expensive Top end camera from the pentax Ilk.
This day and age, reliable autofocus is something we tend to take for granted.
I had an EOS3 and it was indeed an excellent camera, but there is one thing you are overlooking.

As resolution increases achieving consistent pixel level sharpness with PDAF becomes more difficult. Higher resolution and faster glass really challenge any PDAF system. Nikon does have the best PDAF on the market. The biggest problem I have with Pentax AF is the size of the AF points are actually much bigger than the red square indicators seen in the VF, and they don't line up perfectly. The center AF point often locks on to high contrast points well outside the red square. You really have to be careful with what you are locking on to.

One of the big costs associated with DSLRs vs mirror-less is that the mirror/focus screen/prism/PDAF sensor all have to be had calibrated so they all line-up. There is a lot of room for error if not aligned correctly. If you send your body into Pentax calibration they can check these and the improvement can be significant.
01-28-2012, 12:33 PM   #141
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If you read my story:

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/173050-3-lens-...ml#post1795023

I almost returned my K-5 and was thinking to get Nikon D7000 since I currently own the Nikon D70s with 18-200 VR lens that has very good AF performance. The reasons I decided to keep the K-5 is due to the fact that D7000 has AF issue as well and the DA17-70 AF works very well now.
01-28-2012, 12:54 PM   #142
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QuoteOriginally posted by Gimbal Quote
No, the behavior is the same as before. If you press and hold the shutter button the SR icon stays lit no matter what you do, fooling the user that it is ready at all times. But if you only tap the shutter button the SR icon will show the true state, and thus go out if you move around too much. A clear bug IMO.

Systems with the SR in the lenses doesn't have this "problem" as the user clearly sees in the viewfinder that the SR system isn't ready if they move the camera. The picture in the viewfinder is floating around and one needs to wait for it to stabilize, it's very obvious that one have to wait. We only have the icon to watch, and it's fooling us.
Gimbal is absolutely correct, V1.12 does not correct this (i forgot the release on the shutter button step)

I hope everyone tries this - its an eye opener. The SR icon goes out for 2 seconds - which is a long time for ordinary shooting. Maybe this is the smoking gun behind "random OOF"?

If a photographer is relying on SR, and its 3 or 4 step speed reduction, and he tracks the action with the camera or recomposes after focusing, he's left with a blurry image for 2 seconds while the SR becomes effective again. If you rely only on shutter speed, i.e. 1/1.5*FL, then the movement of the camera will not generally cause OOF.

Gimbal, Thank you for reminding me, again

Last edited by philbaum; 01-28-2012 at 01:01 PM.
01-28-2012, 01:08 PM   #143
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QuoteOriginally posted by Winder Quote
I had an EOS3 and it was indeed an excellent camera, but there is one thing you are overlooking.

As resolution increases achieving consistent pixel level sharpness with PDAF becomes more difficult. Higher resolution and faster glass really challenge any PDAF system. Nikon does have the best PDAF on the market. The biggest problem I have with Pentax AF is the size of the AF points are actually much bigger than the red square indicators seen in the VF, and they don't line up perfectly. The center AF point often locks on to high contrast points well outside the red square. You really have to be careful with what you are locking on to.

One of the big costs associated with DSLRs vs mirror-less is that the mirror/focus screen/prism/PDAF sensor all have to be had calibrated so they all line-up. There is a lot of room for error if not aligned correctly. If you send your body into Pentax calibration they can check these and the improvement can be significant.
to be honnest, thats not much of an excuse since everyone else seems to manage it. We are talking about a flagship camera here.
ive certainly no intrest in mirrorless cameras as I barley see them as a camera, unless your talking RF and they are just not suitable for my needs.
Lovely as they are.

01-28-2012, 01:12 PM   #144
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QuoteOriginally posted by philbaum Quote
Gimbal is absolutely correct, V1.12 does not correct this (i forgot the release on the shutter button step)

I hope everyone tries this - its an eye opener. The SR icon goes out for 2 seconds - which is a long time for ordinary shooting. Maybe this is the smoking gun behind "random OOF"?

If a photographer is relying on SR, and its 3 or 4 step speed reduction, and he tracks the action with the camera or recomposes after focusing, he's left with a blurry image for 2 seconds while the SR becomes effective again. If you rely only on shutter speed, i.e. 1/1.5*FL, then the movement of the camera will not generally cause OOF.

Gimbal, Thank you for reminding me, again
This one has made me pick my ears up a bit. Im doing a model shoot tomoz. I was going go manual, but I think I will try risk autofocus again,
making sure SR is off. Watch this space lol
01-28-2012, 02:03 PM   #145
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In 2007, i got my first DSLR, a K10, and outfitted it with the Tamron 18-250. The first thing i bumped into was fuzzy pictures.

Being a faithful reader of pentax forums, i immediately jumped to the conclusion that my fuzzy pictures were a faulty lens. Just to be sure, i slapped it on a tripod and my pictures came out sharp. Ah-ha moment, it wasn't the lens, but the way i was using it. I started using appropriate shutter speeds and the OOFs went away, mostly.

Now jump ahead 4 1/2 years, and someone posts this fascinating discussion of the problems with Nikon's VR system. His advice, if i remember it right, was to generally not use VR unless one is in those specific few situations where it works.

Nikon VR explained

Now jump to the immediately preceding post by me which quotes Gimbal. If you keep your finger on the half press, one would think with the lit hand icon that SR is fully functioning. If you lift your finger on the half press, with the SR system still engage, you find it fading in an out for 2 seconds at a time at every small movement of the camera (except for tiny movements)

The tolerances to maintain a phase focusing system are definitely problematic, but i believe that SR and VR systems are equally problematic for the majority of camera users and are also contributing to OOF shots in all camera brands.

There is a simple way to prevent SR responsible OOF shots. DO NOT USE SR IN PANNING, ACTION MOVEMENT, SIDEWALK SHOOTING, UNLESS ONE UNDERSTANDS THE SR/VR RISK.

I'm not unhappy with my K5 and previous Pentax dslrs. I get really high acceptance rates, like perhaps 95% in focus) for indoor play rehearsal shots shooting when i get all my parameters set correctly. (one of my useful settings was to disable SR) Of course every once in a while, they choose a play with very moody lighting and i struggle, but thats a general limitation iwth all brands. How do i know that? Because i often shoot theatre with photogs who have Canon, Nikon cameras such as the 60D, the D300, D300s, D7000. (We step into the lobby during the break and all complain about the inadequate lighting - misery loves company :-))

Perhaps i'm exaggerating a small bit, but its to get folks attention. There is definitely a problem out there with these systems like SR and VR.
01-28-2012, 02:13 PM   #146
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I hear you Phil.... and its deffo worth a try. Ive used the 16-85 VR on D300 and had no such problems though.
Ive shot racing horses at 6400 ISO using the Nikon 80-200 F2.8 in heavy winds and rain and no track lighting and still had no problem with continuess focus.
like i said, its not, not focussing but miss focussing !
01-28-2012, 02:18 PM   #147
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QuoteOriginally posted by westmill Quote
I hear you Phil.... and its deffo worth a try. Ive used the 16-85 VR on D300 and had no such problems though.
Ive shot racing horses at 6400 ISO using the Nikon 80-200 F2.8 in heavy winds and rain and no track lighting and still had no problem with continuess focus.
like i said, its not, not focussing but miss focussing !
OK, so what shutter speeds were you using on that race track - definitely a challengine situation
01-28-2012, 02:25 PM   #148
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QuoteOriginally posted by philbaum Quote
OK, so what shutter speeds were you using on that race track - definitely a challengine situation
I was aiming at keeping it above 500s lol. I think the last two laps was down to 300 or so but still got the shots Phew ! lol
Each race is just two laps, so only two goes of getting the job done.
I did use the K5 for the presantation shots though between each race.
If i can get it satifactory sorted I would love try it on a race.
01-29-2012, 02:57 PM   #149
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Ok ! Did a bit of a model portfolio today.... Turned off SR !!!!!!
All shot in autofocus.... Scary lol..... Final result..... took 200 pics..... Only one out of focus !
Thats boosted my confidence in the K5 no end. Shame about the one fail, but that is acceptable.

It has to be said for now, that, all the pics were taken from a few inches to prob a max of around 12ft.
All were shot on the Tamron 17-50 and mostly at 50mm but other reaches of the zoom too.
Aprtature was constant at F8 and 160s speed. ISO200. K5 obviously.

Last edited by westmill; 01-29-2012 at 03:27 PM. Reason: added info
01-29-2012, 03:34 PM   #150
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I have to agree and say that I have had more reliable results with SR OFF in the past. I just did a few test shots where I deliberately shot when the SR hand indicator was OUT in the VF. Even though the camera was NOT MOVING there is motion blur in the shot but when I waited for the HAND to light up there was none. I am wondering what is happening when that indicator is off. Is the sensor being moved to a default parking position and SR being reinitialized at that time and thus contributing to the blurred shot count because the sensor is actually moving in the wrong direction?It would explain many of my soft shots with SR on that were a mystery as to the cause (because the actual cameras wasn't moving).

[EDIT: or is the SR system actually functioning and committed to it's first actions rather than what is happening as the shutter is opening? In live mode you can hear the sensor being smacked around quite violently when a telephoto is on the camera so perhaps I'm wrong. Perhaps it's response time isn't as fast as we'd all like to think though]

It's probably a distraction if you have to wait to shoot by checking the hand icon so maybe just leave SR off most of the time. An interesting thought.

Last edited by bossa; 01-29-2012 at 04:29 PM.
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