2 Important K10 Issues that need to be settled for good!! (Please read!)

Started Jan 5, 2007 | Discussions
OP SFT007 Veteran Member • Posts: 5,912
Update - 2nd day and lots of samples

My conclusion: the K10 sometimes FF and sometimes doesnt. I have too many pics to post all of them - but Im trying to figure out why in some scenes it has much more obvious FF than in others. The battery issue makes a big difference! Definetely a big factor. Because sometimes it is spot on (whereas last night with the low battery it wasnt spot on once!!).

But there are some scenes where the camera cannot focus accurately no matter what lens, what level of battery what AF point I select (with the DA50-200 it does better due to the DOF of f4 however in some cases). I will post one so example - I now dont know if there is something wrong with my K10 OR if there is something wrong with the AF of Pentax's in low incandescent lighting. This is an example where it just would not get it right - it states it locks focus but its off as you can see from the crops. All exif will be attached for all shots for those who want to check. Very tasteless purely test shots around my messy apartment so excuse the scene, lighting, composition, etc. All posted shots below are with the FA50 at f2 or smaller - by f4 due to the DOF the FF is masked - but really its still there - its just hiding due to the FF as when I mess with the DA lenses by quci shift focus I can still get better results (slightly).

Full scene - here the FA50 at f1.4 and f2 it just wouldnt get it right. At f4 it looked good due to the DOF - with the DA50-200 it looked the same at f4 - so really its not in focus (just looks like it due to the DOF of f4) and tweaking the DA50-200 by quick shift focus produced a better result at f4 - at f2 with the FA its very obvious as can be seen:

100% AF

100% MF

From that scene I can judge that it is FF the same amount with all lenses as the DA50-200 had the same result as the FA50 at f4 - however at f2 - the FA50 was way off as seen above. So I can conclude that it is indeed FF with all lenses as the DA50-200 did not look better at f4 than the FA50 - if the DA50-200 could do f2 it would be out of focus too.

There are scenes however where the AF is indeed good - and some scenes where its slightly off but close. So im very confused about this all to be honest. I dont know what to do now - should I send my camera in? Should I keep it wait for a firmware? Or is it a hopless cause that Pentax seems to be blessed with for all its dSLR's?

Here is an example where its very close but has slight FF - not bad but its there when viewed at full res.
Full scene

100%AF

100%MF

Here is another FF'ed one.
Full scene

100%AF point of focus chosen by me

100%AF actual point of focus by camera

100%MF

FF again

100%AF

100%MF

Now here is one with good AF in same lighting conditions

100%AF

And another one with good AF this time close-up - love the bokeh of the lens - its the FA50.

100%AF - pretty darn spot on I focused on the most distant flower - this is a tricky one since there are so many items so close to each other in slihgtly varying distance - yet it did pretty good.

Lastly another one with slight FF. Focused in the middle of the cardboard box.

100%AF - see how the slightly closer vodka bottle is a little more in focus.

100%MF - see how the bottle is slihgtly more out of focus now and the box sharper.

I did similar tests and the DA18-55 is terrible at the wide-end - terrible! I can however zoom in fully - lock focus and zoom back out and it does much better. Its however good at the tele-end but I am sure this is no doubt due to the DOF of f5.6!! All in all - Im not sure what to think - can I expect this level of FF from all K10's? Can I expect this level of FF from other brands in similar lighting and similar large apertures of f2, etc.?? Or is my K10 in need of being sent in to Pentax? Sorry for the long post.

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Sinan

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SW Kim Regular Member • Posts: 449
The AF system is a dealbreaker.

When i tried the K10D in lowlight, the AF speed was unacceptable. Event photographers and others who like shooting in low light, beware - this camera is NOT for you. My unit didnt have problems with AF accuracy though.

However, i have read posts like yours before. Some units appear to have this problem of misfocusing under certain lighting conditions.

rennie12 Senior Member • Posts: 2,844
Sinan - I made a mistake in my earlier post -

The LTD 77 is indeed the only lens I use in incandescent light. However, I had completely forgotten that I did encounter severe SR and focusing problems when the battery went way down. The battery lasted so long that I simply forgot that it hadn't been charged, and it actually stopped working altogether shortly after I was puzzling over the SR problems focusing problems.

I concluded that this was normal when the battery was low and resolved to get a second battery and simply not ever work with the battery below about 250 shots.

I put this out of my mind after making this decision, and didn't think about it when I made my earlier post about no focusing problems and in incandescent light.

I certainly have had none since resolving not to work with a low battery.

This is a minor nuisance but I'm afraid that if one is going to use the K10D with all the other great features plus the inexpensive stabilized lenses there are just some feature peculiarities that one is going to have to accept as the price of saving money.

I love the K10D BUT if I had $1 million to spend on my photographic equipment I would have no hesitation about switching to Canon -- the sensors are the best in the world and their lens selection is, I feel, the best. The one exception is that of course they have no stabilized fast primes.
--
bill wilson

SW Kim Regular Member • Posts: 449
I would say the Fuji

sensors are the best in the world.

OP SFT007 Veteran Member • Posts: 5,912
Re: Sinan - I made a mistake in my earlier post -

Bill - exactly what happened to me yesterday - it was utterly useless with the battery being close to depleted - which I didnt know about since the battery indicator is terrible and was still showing a full charge when I started testing but then shortly after went down very quick and hence the completely unacceptable results. But unfortunately - I am sure mine is still FF'ing in some cases at fast apertures (ie. f2) even with the battery fully charged. I have a theory that maybe if you notice all the scenes with FF have some sort of glass that is reflecting light a little and the 2 examples that I posted that dont have FF dont have any glass that is reflecting anything! I wonder if the bottle or the, metal shiny base plate of the lamp, the slihgt reflection off my photo frame on the wall etc. are putting the AF off. Because with non reflecting subjects in low-light it did do better - I will keep testing this actually - maybe the Pentax AF is just more easily fooled by such things? But I just noticed it and maybe it has something to do with it? I will post back if this theory holds any weight.

rennie12 wrote:

The LTD 77 is indeed the only lens I use in incandescent light.
However, I had completely forgotten that I did encounter severe SR
and focusing problems when the battery went way down. The battery
lasted so long that I simply forgot that it hadn't been charged,
and it actually stopped working altogether shortly after I was
puzzling over the SR problems focusing problems.

I concluded that this was normal when the battery was low and
resolved to get a second battery and simply not ever work with the
battery below about 250 shots.

I put this out of my mind after making this decision, and didn't
think about it when I made my earlier post about no focusing
problems and in incandescent light.

I certainly have had none since resolving not to work with a low
battery.

This is a minor nuisance but I'm afraid that if one is going to use
the K10D with all the other great features plus the inexpensive
stabilized lenses there are just some feature peculiarities that
one is going to have to accept as the price of saving money.

I love the K10D BUT if I had $1 million to spend on my photographic
equipment I would have no hesitation about switching to Canon --
the sensors are the best in the world and their lens selection is,
I feel, the best. The one exception is that of course they have no
stabilized fast primes.
--
bill wilson

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Sinan

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D TONG Senior Member • Posts: 2,559
Your first post about FA50mm relating to some issue????

Sinan Tarlan wrote:

Dude, you are either very very confused - or If youre trying to say
something - get to the point!

I never said the FA50 had issues!! The lens is great - period, end
of story - what is this obsession with the FA50?? Are you even
reading my posts? I am not criticising the FA50 - This thread is
not about the FA50** The first paragraph was just a point that I am
glad I got my FA50 - thats it!!

Sinan Tarlan wrote:
copied from original post

Since I got the FA50 f1.4 - I can confirm two things:

1. Metering using the aperture ring is off with the green button in M > mode. The camera underexposes in indoor lighting at the large > apertures of f1.4~f2 and a little at f2.8 but is good at f4 and and more > with both M 50mm AND my brand new FA50mm. The metering is > slightly different with both (probably due to the aperture blades being > old with the M lens) but they both underexpose at the fast apertures - > so this is a metering issue with the camera.

Using Av mode however by setting the lens on the A position with the > FA50 - I am getting correct exposures all the time at all apertures - this > problem only happens when I use the aperture ring (which can only be > used in M mode I believe).

Well there was apparently no issue at all???? Was it????? .

Daniel, Toronto
http://www.pbase.com/danieltong

D TONG Senior Member • Posts: 2,559
So there is no issue at all as far as we can see

D TONG wrote:

Sinan Tarlan wrote:

Dude, you are either very very confused - or If youre trying to say
something - get to the point!

I never said the FA50 had issues!! The lens is great - period, end
of story - what is this obsession with the FA50?? Are you even
reading my posts? I am not criticising the FA50 - This thread is
not about the FA50** The first paragraph was just a point that I am
glad I got my FA50 - thats it!!

Sinan Tarlan wrote:

copied from original post

Since I got the FA50 f1.4 - I can confirm two things:

1. Metering using the aperture ring is off with the green button in M > mode. The camera underexposes in indoor lighting at the large > apertures of f1.4~f2 and a little at f2.8 but is good at f4 and and more > with both M 50mm AND my brand new FA50mm. The metering is > slightly different with both (probably due to the aperture blades being > old with the M lens) but they both underexpose at the fast apertures - > so this is a metering issue with the camera.

Using Av mode however by setting the lens on the A position with the > FA50 - I am getting correct exposures all the time at all apertures - this > problem only happens when I use the aperture ring (which can only be > used in M mode I believe).

Well there was apparently no issue at all???? Was it????? .

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OP SFT007 Veteran Member • Posts: 5,912
Re: So there is no issue at all as far as we can see

Daniel, no issue with what? With the FA50mm? If you would write more than one sentence it would help trying to decipher what youre trying to get at! If youre talking about no problem with the FA50- yes that is correct - there is NOTHING wrong with the FA50mm and I never said there was.

Any problem that I am getting (such as FF and inaccurate metering using the aperture ring) with the FA50mm mounted on my K10 is due to the fault of the K10!! Not the FA50!! I know this because I get inaccurate metering with the M lens too using the aperture ring and I get inaccurate focusing with my DA lenses too so its not the FA50mm!! I never said it was - why are you going on and on about the FA50mm?? I really dont know what else to say to you at this point.

D TONG wrote:

D TONG wrote:

Sinan Tarlan wrote:

Dude, you are either very very confused - or If youre trying to say
something - get to the point!

I never said the FA50 had issues!! The lens is great - period, end
of story - what is this obsession with the FA50?? Are you even
reading my posts? I am not criticising the FA50 - This thread is
not about the FA50** The first paragraph was just a point that I am
glad I got my FA50 - thats it!!

Sinan Tarlan wrote:

copied from original post

Since I got the FA50 f1.4 - I can confirm two things:

1. Metering using the aperture ring is off with the green button in M > mode. The camera underexposes in indoor lighting at the large > apertures of f1.4~f2 and a little at f2.8 but is good at f4 and and more > with both M 50mm AND my brand new FA50mm. The metering is > slightly different with both (probably due to the aperture blades being > old with the M lens) but they both underexpose at the fast apertures - > so this is a metering issue with the camera.

Using Av mode however by setting the lens on the A position with the > FA50 - I am getting correct exposures all the time at all apertures - this > problem only happens when I use the aperture ring (which can only be > used in M mode I believe).

Well there was apparently no issue at all???? Was it????? .

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Sinan

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OP SFT007 Veteran Member • Posts: 5,912
Re: So there is no issue at all as far as we can see

When I said I can confirm the issues - I am referring to the CAMERA issues not the FA50mm issues - I just use the FA50 as my tool to pinpoint the problems I have hinted at before as now I have several lenses that I can use to confirm the problems. That is what I am confirming - not that the FA is having these issues but the M - as if you reread it I state that both the M and the FA do this - not the FA exclusively. I am not doing a lens test. Is it clear now?

Sinan Tarlan wrote:
Daniel, no issue with what? With the FA50mm? If you would write
more than one sentence it would help trying to decipher what youre
trying to get at! If youre talking about no problem with the FA50-
yes that is correct - there is NOTHING wrong with the FA50mm and I
never said there was.

Any problem that I am getting (such as FF and inaccurate metering
using the aperture ring) with the FA50mm mounted on my K10 is due
to the fault of the K10!! Not the FA50!! I know this because I get
inaccurate metering with the M lens too using the aperture ring and
I get inaccurate focusing with my DA lenses too so its not the
FA50mm!! I never said it was - why are you going on and on about
the FA50mm?? I really dont know what else to say to you at this
point.

D TONG wrote:

D TONG wrote:

Sinan Tarlan wrote:

Dude, you are either very very confused - or If youre trying to say
something - get to the point!

I never said the FA50 had issues!! The lens is great - period, end
of story - what is this obsession with the FA50?? Are you even
reading my posts? I am not criticising the FA50 - This thread is
not about the FA50** The first paragraph was just a point that I am
glad I got my FA50 - thats it!!

Sinan Tarlan wrote:

copied from original post

Since I got the FA50 f1.4 - I can confirm two things:

1. Metering using the aperture ring is off with the green button in M > mode. The camera underexposes in indoor lighting at the large > apertures of f1.4~f2 and a little at f2.8 but is good at f4 and and more > with both M 50mm AND my brand new FA50mm. The metering is > slightly different with both (probably due to the aperture blades being > old with the M lens) but they both underexpose at the fast apertures - > so this is a metering issue with the camera.

Using Av mode however by setting the lens on the A position with the > FA50 - I am getting correct exposures all the time at all apertures - this > problem only happens when I use the aperture ring (which can only be > used in M mode I believe).

Well there was apparently no issue at all???? Was it????? .

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Sinan

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Sinan

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OP SFT007 Veteran Member • Posts: 5,912
More on FF'ing

Hmm, not sure I can confirm the reflection theory - it is doing it in other scenes too - in fact I just tried a shot from my balcony and focused on another balcony at f2 and yes - its soft and FF is visible so this isnt necessarrily only in indoor low-lighting either - its almost in all low-light situations as it just happened outdoors too. I am 99% certain it will be fine tomorrow during the day at f2 with the FA50mm - I will test that tomorrow too and see if there is any FF visible - but Im seriously doubting there is - will update on that issue tomorrow during the day.

situations

Sinan Tarlan wrote:
Bill - exactly what happened to me yesterday - it was utterly
useless with the battery being close to depleted - which I didnt
know about since the battery indicator is terrible and was still
showing a full charge when I started testing but then shortly after
went down very quick and hence the completely unacceptable results.
But unfortunately - I am sure mine is still FF'ing in some cases at
fast apertures (ie. f2) even with the battery fully charged. I have
a theory that maybe if you notice all the scenes with FF have some
sort of glass that is reflecting light a little and the 2 examples
that I posted that dont have FF dont have any glass that is
reflecting anything! I wonder if the bottle or the, metal shiny
base plate of the lamp, the slihgt reflection off my photo frame
on the wall etc. are putting the AF off. Because with non
reflecting subjects in low-light it did do better - I will keep
testing this actually - maybe the Pentax AF is just more easily
fooled by such things? But I just noticed it and maybe it has
something to do with it? I will post back if this theory holds any
weight.

rennie12 wrote:

The LTD 77 is indeed the only lens I use in incandescent light.
However, I had completely forgotten that I did encounter severe SR
and focusing problems when the battery went way down. The battery
lasted so long that I simply forgot that it hadn't been charged,
and it actually stopped working altogether shortly after I was
puzzling over the SR problems focusing problems.

I concluded that this was normal when the battery was low and
resolved to get a second battery and simply not ever work with the
battery below about 250 shots.

I put this out of my mind after making this decision, and didn't
think about it when I made my earlier post about no focusing
problems and in incandescent light.

I certainly have had none since resolving not to work with a low
battery.

This is a minor nuisance but I'm afraid that if one is going to use
the K10D with all the other great features plus the inexpensive
stabilized lenses there are just some feature peculiarities that
one is going to have to accept as the price of saving money.

I love the K10D BUT if I had $1 million to spend on my photographic
equipment I would have no hesitation about switching to Canon --
the sensors are the best in the world and their lens selection is,
I feel, the best. The one exception is that of course they have no
stabilized fast primes.
--
bill wilson

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Sinan

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Jan Moren Veteran Member • Posts: 3,745
Re: So there is no issue at all as far as we can see

D TONG wrote:

Well there was apparently no issue at all???? Was it????? .

The K10D meters inaccurately in M mode with manual lenses. That is an issue.

You might want to moderate your use of question marks, by the way; we only get so much punctuation in our lives.

Brett St Pierre
Brett St Pierre Veteran Member • Posts: 7,033
Re: Sinan, Brett

JeffJS wrote:

Brett, Yes, I'm aware that contrast is required for AF to work
reliably. Your description though Might serve to explain why it is
that the kit lens (f3.5) and the Tamron Di 70-300 rarely fail. That
is, if I understand what you're saying correctly.

Yes, you are understanding me correctly then but my proposal is still speculation that gets debated here as I said. On the other hand, a night bright viewfinder from a fast lens with small DOF is a better way to manually focus!

With your dog shot, I can see the difficulty of any AF system ton handle that but as you say, there are ways to handle it.

Failing all that, I've
already earmarked my camera allowance for a KatzEye screen so I can
manually focus the way I'm use to doing it. Split prism.

I am using the KatzEye with split image/micro-prism collar out of my *istD. I took the first 800 photos with the K10D with the standard screen and now I will take a few hundred with this to test the metering issues that may come of it (we have done some fairly testing with KatzEyes before in the *istD). I do like the split image as for MF and as focus confirmation in AF but am unsure whether I will spend another US$150 (with grid lines) on another screen designed for the K10D if I am satisfied the old screen will work for me. Watch this space....

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JeffJS Senior Member • Posts: 2,886
Re: Sinan, Brett

Brett St Pierre wrote:

JeffJS wrote:

Brett, Yes, I'm aware that contrast is required for AF to work
reliably. Your description though Might serve to explain why it is
that the kit lens (f3.5) and the Tamron Di 70-300 rarely fail. That
is, if I understand what you're saying correctly.

Yes, you are understanding me correctly then but my proposal is
still speculation that gets debated here as I said. On the other
hand, a night bright viewfinder from a fast lens with small DOF is
a better way to manually focus!

This theory and discussion has me wondering... The FA 50 is meant, or designed to be used, on a film camera. Whereas the DA Kit lens as well as the Tamron Di are both meant for digital (using examples from my own camera bag). What I'm wondering, is if the larger image circle on the FA has stray light bouncing around inside the camera, tending to confuse the AF system on the camera. These 3 are the only autofocus lenses I own at the time so I can only go by what I'm seeing (or not seeing)..

Just a thought..
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Still happy with the K10d (in spite of the pixel peepers)

*isteve Veteran Member • Posts: 9,509
Re: Update - 2nd day and lots of samples

Sinan Tarlan wrote:

I did similar tests and the DA18-55 is terrible at the wide-end -
terrible! I can however zoom in fully - lock focus and zoom back
out and it does much better. Its however good at the tele-end but I
am sure this is no doubt due to the DOF of f5.6!! All in all - Im
not sure what to think - can I expect this level of FF from all
K10's? Can I expect this level of FF from other brands in similar
lighting and similar large apertures of f2, etc.?? Or is my K10 in
need of being sent in to Pentax? Sorry for the long post.

Well mine is less than perfect in low light too unless I use an "AF friendly" focus target. I have a mosiac tiled worktop which all my lenses focus perfectly on all the time, even of they have trouble with "standard" focus targets.

Same was true of all my film cameras (Nikon, Minolta) but I didnt have the luxury of testing them exhaustively. Same was also true of the *istD and DS, and my friends that shoot Nikon and Canon low-midrange systems report similar issues even in good light (the Canon 10D was notorious). However these cameras tend to report a good lock even when not in focus. I have read many threads on the Canon forums about focus misses too and some have posted here.

AF simply is not foolproof especially if the level of contrast is low. I also thing AF sensors are more sensitive in the middle of the spectrum (green) which is not as prevalent in incandescent light (so contrast is even lower than it looks from the scene). I have NEVER had a camera that had perfect AF, though you will find the pro bodies (D2X, 1D etc) are generally much better, but then they are also much higher spec.

Also, cameras are calibrated post assembly for 2 or 3 standard lenses. There is a tolerance and margin for error involved especially if you are using wider focal lengths.

If your camera is focusing well in good light, then I suggest there is nothing much Pentax can do. If its out in good light, then they may be able to adjust it.

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Steve
Pixel peepers miss the big picture.
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Brett St Pierre
Brett St Pierre Veteran Member • Posts: 7,033
Re: Sinan, Brett

JeffJS wrote:

Brett St Pierre wrote:

JeffJS wrote:

Brett, Yes, I'm aware that contrast is required for AF to work
reliably. Your description though Might serve to explain why it is
that the kit lens (f3.5) and the Tamron Di 70-300 rarely fail. That
is, if I understand what you're saying correctly.

Yes, you are understanding me correctly then but my proposal is
still speculation that gets debated here as I said. On the other
hand, a night bright viewfinder from a fast lens with small DOF is
a better way to manually focus!

This theory and discussion has me wondering... The FA 50 is meant,
or designed to be used, on a film camera. Whereas the DA Kit lens
as well as the Tamron Di are both meant for digital (using examples
from my own camera bag). What I'm wondering, is if the larger image
circle on the FA has stray light bouncing around inside the camera,
tending to confuse the AF system on the camera. These 3 are the
only autofocus lenses I own at the time so I can only go by what
I'm seeing (or not seeing)..

Nope, don't think so. I have a number of fast lenses for 35mm film format and I haven't had an issue with them (and very rarely the 50/1.4) but all of them a more contrasty in themselves wide open (e.g. 31/1.8 and 77/1.8)....

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(unknown member) Senior Member • Posts: 1,807
Re: 2 Important K10 Issues - Excellent Thread!

Congratulations to all participants!

This is the BEST forum I have seen.
Very objective and helpful.
At this writing, everyone seem to focus on the issue.

A pleasure to read everyone's contribution.
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OP SFT007 Veteran Member • Posts: 5,912
Daylight experience and observations about FF

Thanks for the extensive reply Steve - I appreciate it very much.

Well I just threw my FA50 on the K10 and took some shots on this very overcast day (so nice even flat lighting) at f1.4 and f2 and it is absolutely spot on perfect. Couldnt focus any better.

So its obvious the problem is low artificial light only. I found this article concerning the AF accuracy of Pentax SLR's with regards to color temp, etc. interesting by RiceHigh: http://www.geocities.com/ricehigh/DS_AF_Dependency_on_KEV.html

As for the 18-55 - it also managed to focus just fine at the wide-end and I didnt have to zoom in fully lock focus and then zoom back out to 18mm. So there isnt anything wrong with any of the lenses - I am certain of this. Its amazing though just how bad the 18-55 was at the 18mm end last night - a huge difference between last night and today shooting in flat natural outdoor light. I wonder if it gets worse as you shoot WA and better as you do tele in the low-light artifical lighting situations. I guess that may make sense as the wider the angle the more the aritificial light is going to be coming in from all directions and the more it may put the AF off.

So are you imlpying that all other cameras like the D80, Xti, 30D, A100, etc.. will, have the same problems I encountered above. Of course a fast lens (like a f1.4 or f2) must be used to really pinpoint the degree of accuracy. I cant see how a $1000 camera cant focus in anything but natural light? I would love to be able to be compare it to my Fuji F30 but of course even at f2.8 with the F30 - we have HUGE DOF so a direct comparison cant be made unfortunately. If I stop the K10 down to something like F8 or so (which is still less DOF than the f2.8 of the F30 I believe) I also get good focus - but thats hardly desirable.

So I know for a fact now that with all my lenses (FA50, DA18-55 and DA50-200) I am getting good focus outdoors in natural light but bad focus in artificial low-light. What to do? Will Pentax not consider this faulty? I certainly think its faulty and I would expect a $1000 camera to not require so much work to get a good shot indoors. I am going to call them on Monday and see what they say - I will explain to them my exact experience. I wish I had a D80 with a 50mm f1.4 or f1.8 lens to compare to side by side - that would reassure me. If the D80 did better than its just pure fact that the Pentax's cant focus in artificial light and that would be very dissapointing for me, if the D80 acted the same way - than all is good and I would know its a universal problem for all consumer dSLR's.

*isteve wrote:

Sinan Tarlan wrote:

I did similar tests and the DA18-55 is terrible at the wide-end -
terrible! I can however zoom in fully - lock focus and zoom back
out and it does much better. Its however good at the tele-end but I
am sure this is no doubt due to the DOF of f5.6!! All in all - Im
not sure what to think - can I expect this level of FF from all
K10's? Can I expect this level of FF from other brands in similar
lighting and similar large apertures of f2, etc.?? Or is my K10 in
need of being sent in to Pentax? Sorry for the long post.

Well mine is less than perfect in low light too unless I use an "AF
friendly" focus target. I have a mosiac tiled worktop which all my
lenses focus perfectly on all the time, even of they have trouble
with "standard" focus targets.

Same was true of all my film cameras (Nikon, Minolta) but I didnt
have the luxury of testing them exhaustively. Same was also true of
the *istD and DS, and my friends that shoot Nikon and Canon
low-midrange systems report similar issues even in good light (the
Canon 10D was notorious). However these cameras tend to report a
good lock even when not in focus. I have read many threads on the
Canon forums about focus misses too and some have posted here.

AF simply is not foolproof especially if the level of contrast is
low. I also thing AF sensors are more sensitive in the middle of
the spectrum (green) which is not as prevalent in incandescent
light (so contrast is even lower than it looks from the scene). I
have NEVER had a camera that had perfect AF, though you will find
the pro bodies (D2X, 1D etc) are generally much better, but then
they are also much higher spec.

Also, cameras are calibrated post assembly for 2 or 3 standard
lenses. There is a tolerance and margin for error involved
especially if you are using wider focal lengths.

If your camera is focusing well in good light, then I suggest there
is nothing much Pentax can do. If its out in good light, then they
may be able to adjust it.

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Sinan

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photogerald Senior Member • Posts: 1,798
Re: Update - 2nd day and lots of samples

Sorry I can't comment on the AF issues, but I was wondering if you could comment on how easy it is to manual focus with the K10D? Because judging from the samples you posted it appears you don't have any problems at all! Are you using the Kats-Eye screen by any chance? If not, what's your secret? Do you have very good eyesight? Or does the large viewfinder play a big part?

I remember that back when I had my PZ-1p, when using manual focus lenses I would rely on the focus indicator most of the time.

OP SFT007 Veteran Member • Posts: 5,912
Re: Update - 2nd day and lots of samples

I use the focus indicator and VF as a guide and then since I know it FF's a little I tweat the focusing a little to compensate for the FF. With the FA50mm its easy using the VF as its bright and big - its very difficult however with the DA18-55 at the wide-end.

photogerald wrote:

Sorry I can't comment on the AF issues, but I was wondering if you
could comment on how easy it is to manual focus with the K10D?
Because judging from the samples you posted it appears you don't
have any problems at all! Are you using the Kats-Eye screen by any
chance? If not, what's your secret? Do you have very good eyesight?
Or does the large viewfinder play a big part?

I remember that back when I had my PZ-1p, when using manual focus
lenses I would rely on the focus indicator most of the time.

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Sinan

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Alfisti Veteran Member • Posts: 6,649
Told ya a week ago

Under that lighting it appears Pentax has a clear weakness that to me, is very hard to argue with.

I'd ask for a recalibration and if that does nothing then return it and go a D80 if youy can afford the price of Nikon glass and the extra size and weight.

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