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03-12-2011, 07:18 AM   #226
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QuoteOriginally posted by ursamajor Quote
And he's not the only one. A friend of mine, from a local forum did some rapid tests and found ff too. Even in daylight type artificial light.
See the pictures attached and the original thread about Pentax 5.
The FF here looks consistent.
Perhaps a global AF microadjustment would resolve the issue in this case?

03-12-2011, 07:20 AM   #227
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On the US site now

I just checked the US site and firmware 1.03 is now available. I don't believe this had been reported so far.
03-12-2011, 07:39 AM   #228
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@Kunzite
Well, maybe you're right. Now I provoked you: maybe it's the time you take the test seriously.

PS: by the way, I just getting ready to tell you about my post here, using your photos.
03-12-2011, 07:53 AM   #229
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All these people running "tests", are they making sure that their chart is perfectly parallel to the sensor plane? (if it's out by any amount, they will think they have a focus error), are they taking field curvature of the lens into account? (if they measure AF with the center point and take a reading from somewhere off to the side, they will definitely show focus error).


Until people start publishing the methodology of their "test methods", and are ensuring that they are taking these things into account, they aren't testing anything, they are just wasting their time on a meaningless pseudo scientific venture.
Most people couldn't set up a truly accurate test bench for this sort of stuff if their lives depended on it.

03-12-2011, 08:53 AM - 1 Like   #230
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QuoteOriginally posted by dgaies Quote
I think there is no question the new firmware is a major improvement. With the previous firmware, the threshold where FF would occur was around 2-4 EV with my K-5 (depending on the lens and type of light). With version 1.03 that threshold has shifted close to 0EV. The FF shift below 1 EV can be mitigated with the use of the AF-assist lamp (if the situation allows it)....
This has also been my experience. Up to about .5 EV I am getting the same focus results with LV or normal auto focus. Then I am getting slight FF under that point (assuming I leave the focus assist lamp off). For ME [and I know mileage may vary] and my shooting style, I consider this issue fixed.
03-12-2011, 09:06 AM   #231
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QuoteOriginally posted by dave2k Quote
I just checked the US site and firmware 1.03 is now available. I don't believe this had been reported so far.
I started a thread yesterday afternoon stating that it was now available from the Pentax USA site.

k-5-fw-v1-03 now available at Pentax USA web site
03-12-2011, 10:24 AM   #232
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QuoteOriginally posted by Wheatfield Quote
All these people running "tests", are they making sure that their chart is perfectly parallel to the sensor plane? (if it's out by any amount, they will think they have a focus error), are they taking field curvature of the lens into account? (if they measure AF with the center point and take a reading from somewhere off to the side, they will definitely show focus error).


Until people start publishing the methodology of their "test methods", and are ensuring that they are taking these things into account, they aren't testing anything, they are just wasting their time on a meaningless pseudo scientific venture.
Most people couldn't set up a truly accurate test bench for this sort of stuff if their lives depended on it.

Really? very assumptive of you.

A test should be accurate enough to show the condition being tested for. My tests to compare my K20D and K-5 AF in low light were more than accurate enough for the purpose they were designed for. There was no need to carefully align the chart to the nearest millimetre.

Real world pictures aren't like that anyway. All I know is that my K-5 Front focusses in low light where my K20D focusses.

If and when I decide to do some scientific study on Autofocussing you can be sure I will make sure everything is aligned with the utmost accuracy.

However I just want my 1000 camera to accurately focus in conditions where it's expected to ( i.e within it's specification )
03-12-2011, 11:15 AM   #233
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QuoteOriginally posted by Wheatfield Quote
Most people couldn't set up a truly accurate test bench for this sort of stuff if their lives depended on it.
And I have similar doubts about most people's ability to 'calibrate' their lenses.
The term seems interchangeable with 'bollocks up my camera', IMHO.

03-12-2011, 11:46 AM   #234
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QuoteOriginally posted by Graham67 Quote
And I have similar doubts about most people's ability to 'calibrate' their lenses.
The term seems interchangeable with 'bollocks up my camera', IMHO.
Thanks for confirming my wisdom in not attempting it.
03-12-2011, 12:22 PM   #235
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QuoteOriginally posted by Graham67 Quote
And I have similar doubts about most people's ability to 'calibrate' their lenses.
The term seems interchangeable with 'bollocks up my camera', IMHO.

Well I can't speak for anyone else, but after calibrating my lenses I got sharp pictures.
03-12-2011, 12:39 PM   #236
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QuoteOriginally posted by Smeggypants Quote
Well I can't speak for anyone else, but after calibrating my lenses I got sharp pictures.
Yeah, but you probably know what you're doing.
03-12-2011, 01:26 PM   #237
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QuoteOriginally posted by dadipentak Quote
Yeah, but you probably know what you're doing.
Well I dunno, but whatever I'm doign it works.

btw if you're not comfortable with focus charts and things then another, but laborious way of doing it is to set up on a tripod and choose a subject parralell to the sensor in good light. Then take 21 pics from -10 through to +10. get the AF to work from nearest every time.

then find the pic that is the sharpest leave the lens AF calibration set at that. if you find 0 is the sharpest then at least you know it was always OK
03-13-2011, 05:56 AM   #238
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QuoteOriginally posted by Smeggypants Quote
However I just want my 1000 camera to accurately focus in conditions where it's expected to ( i.e within it's specification )
I would like that to ive done some test with my replacements camera with the latest firmware, and auto-focus is not good.

My test lens was the pentax 100mm macro wr.
if i focus on a small thing on the table, it front focys quite alot. this was indoor in poor light. (


I hope it works better outdoor at bugs.

But Im already waiting for the 1.04 firmware.

Last edited by Purusam; 03-13-2011 at 05:58 AM. Reason: spelling
03-13-2011, 06:59 AM - 1 Like   #239
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Smeggypants, it is too bad that you never responded to my request to test your K20D for back-focus under daylight.

A quick glance at your corresponding test shots tells me that your K20D indeed back-focuses under daylight. Mystery solved, AFAIC. Your K20D doesn't show a miraculous deviation from other K20Ds and I believe you could get (pretty much) the same behaviour from your K-5 by just using the same AF bias. Whether that's acceptable is another question, but I'm no longer puzzled by what you described as the K20D beating the K-5 in focus accuracy.

P.S.: I hope I didn't offend you by addressing you as "Smeggy one" in the post I referenced. I thought it was funny and wouldn't expect someone with a user name like yours to be offended. Sorry if you found it offensive nevertheless.
03-13-2011, 08:06 AM   #240
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Thanks, but I've seen some of the calculators. However, I think you answered the question I had... EV is determined 'after the shot', correct?

I've seen so many post here that they took a photo with "2 EV" for example, and have been assuming that they set the lighting at that value prior to shooting, when it appears that EV is taken from analyzing the parameters of photo data, or at least calculated by looking at the basic settings the camera decides to set with it's built in light meter. IOW, I could dial up or down my lighting and look at the parameters the camera calculates for correct exposure (ISO, shutter, aperture & ev), plug them into one of the programs some of you suggested here and I would have an EV number, is that right?

Again, sorry for off topic, I see you are all dealing with a very important and possibly frustrating issue. I hope this gets sorted out soon for all of you. I really want a k5 but have to decide if this issue isn't fixed, is it going to affect my type or style of shooting to the extent that using the camera would result in a negative experience for me.

Bill

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QuoteOriginally posted by Smeggypants Quote
I use this ...


Ultimate Exposure Computer


There is a formula but I don't have excel installed and I've yet to find an online calc
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