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

Mine is focusing just fine - in fact its fast and sure in its lock even wide open at F1.4. Are you sure there isnt something wrong with yours?

My DA18-55 kit lens is by far the worst at the wide-end (and I would expect it to be) and my DA50-200 is also very good just like the FA50 with the freshly charged battery.

In fact my DA18-55 is front focusing quite slightly at the wide-end but not by much- but now I know its not a camera problem - though I have found a workaround which is to zoom in fully to 55mm lock the focus at that focal lenght and zoom out to 18mm - works like a charm - and I definetely get better results that way than at locking focus at 18mm - though it is also much much better than before - so it seems it really was a battery issue and not a camera issue - the 18-55 FF at 18mm is due to the lens I am sure (or I hope!) I will see how my Sigma 18-50 f2.8 fares compared to it once that arrives.

JeffJS wrote:

you get a little more exposure with that FA 50 1.4.. Being one of
the first lenses I purchased after deciding to go Pentax Dslr (see
sig for which one), I was very anxious to try it out. I've noticed
several situations, particularly dark room lighting, where this
lens Hunts A LOT for a focal point. Sometimes gets it right,
sometimes not. I doubt it's the camera because the Kit lens, that's
right, the 18-55 slow, cheap, kit lens nails it almost everytime.
The Tamron 70-300 Di also nails it almost everytime. Not only that
but the exposure is right with the kit lens. I'm not knocking the
FA 50 per say, but for what it cost, I did expect better from it.
I've noticed too that it seems to consistantly underexpose by a
full stop, full battery or not. That's using autoexposure modes,
viewing the histogram after the photo is taken. Again, this isn't
really to knock the lens because I do get nice results from it, but
I can match or better the performance with my SMC-M 50 f1.4. I'd
gladly trade the FA 50 1.4 and some change for a nice SMC-M 50 f1.2.
--
http://photobucket.com/albums/v285/jjmel
Still happy with the K10d (in spite of the pixel peepers)

Trust me - the battery life made a HUGE difference. A difference like night and day in fact - I also read that the SR is not as effective once the battery life is close to being diminished so I guess its important with an SLR to keep your battery healthy - this wasnt the case with my little compact F30 so I always used it until the battery died - I wont be doing that with the K10 and I will probably order a spare battery sometime soon then.

Thanks Rupert - glad to see that the Green button in M mode is not very reliable - that wasnt my major problem since It always acts in the same way I know how much to compensate it by when shooting with the M - it was the focusing issue that was getting to me and Im very glad that having a fully charged battery made a world of difference and now my FA50 is focusing like a champ!

Rupert60 wrote:

No focus problems.
The Green button when used in M mode is absolutely worthless.
Worked perfect on my DS. I expect Pentax to repair this one way or
another, probably firmware?
--
'This is more serious than I thought.....but it is still fun!
http://www.pbase.com/rupertdog Take a look- It's Free!

I see what youre saying - that was exactly what was happening when my battery was low - I couldnt even tell what the hell it was trying to focus on.

Im actually curios as to the size of the AF point. How big is it? Is it exactly the size of the red box that lights up - is exactly there - or is it a little bigger than that?

JeffJS wrote:

I may not have explained it as clearly as I could have.. When the
lens focuses, it focuses just fine. In fact, they all do. I've not
noticed any front or back focus issues with any of them. Either
they are dead on, or I can't figure out what spec of dust in the
air they chose to focus on. Because when the autofocus photos are
out of focus, they are WAAAAAY out of focus. Not just a little bit
but focused at infinity on a closup subject. It seems to happen
more with the FA50 than the rest. It may be because that's the one
I paid the most for. This is only in certain conditions however,
dark indoor room, as stated previously. I haven't had a lot of
chance to try it outside. With respect to the exposure, I actually
prefer a little underexposure. Coming into DSLR from B&W film,
expose for shadows, process for highlights.

I will freely admit that I'm still learning how to use this new
medium (to me) called DSLR and many of my problems could be user
error. In my mind, I'm sometimes the first to accuse (though I
rarely put it into writing) someone of blaming the equipment rather
than the operator when problems pop up with our beloved Pentax
gear. No, I don't think there's anything wrong with my copy, I'm
probably expecting too much from it. Quickly Autofocus on my black
lab in a dark room for instance. Like I said, Some situations......
--
http://photobucket.com/albums/v285/jjmel
Still happy with the K10d (in spite of the pixel peepers)

JeffJS wrote:

you get a little more exposure with that FA 50 1.4.. Being one of
the first lenses I purchased after deciding to go Pentax Dslr (see
sig for which one), I was very anxious to try it out. I've noticed
several situations, particularly dark room lighting, where this
lens Hunts A LOT for a focal point. Sometimes gets it right,
sometimes not. I doubt it's the camera

here is a comment that gets debated occassionally and I am not convinced but it has some merit...

.. AF rwquires a degree of subject contrast for the AF system to get enough data to process a lock, you see this when you try to focus on a flat object like a plain wall, it just won't do it. The FA50/1.4 images at f/1.4 produce very low contrast, it doesn't start to get normal lens contrast until stopped down f/2 or more (but not as bad as say the 50/1.2) - it's just the nature of a very fast aperture lens. What is the very low contrast of the lens (because at AF time it is wide open) disadvantages the cameras AF system to get sufficient contrast in certain conditions?

Just an idea... would the out-of-production FA50/1.7 be better in that regard? (don't know, I sold mine to get the f/1.4 version and I had had no trouble with either but then i don't put them under any AF stress, i MF in tricky conditions)

There'd been speculation before that the poor AF performance in lower light might be happening when the batteries are low... and now you've nailed it down. That's good to know. We've also heard that the SR gets weak when the battery is low. So I guess the battery life statement should say, like, "300 shots with full performance, 400 more shots with reduced performance".

I would say thats a very fair assestment - the AF performance seems to go down quite rapidly actually and I woudlnt be surprised if your figures are dead on!

Ive already taken like a few hundred test shots since I charged the battery and already I can see the AF starting to be more hit and miss! It was very sure when I first took it out the charger with the battery full but now its not as good and I bet if I take another 100 shots it is going to keep on getting worse. Its interesting though that it affects it in indoor lighting - shouldnt this in theory also affect it in good outdoor lighting too? I am going to throw my battery in the charger again now and leave it overnight and after I get back from work tomorrow see again how it does with the full charge - I think this theoruy may be correct though - up to around 300 shots and then from there it starts to be hit and miss and then by the end of the life completelly miss! I wonder if it starts missing if the battery is almost dead in daylight too? I havent tested this.

paulkienitz wrote:

There'd been speculation before that the poor AF performance in
lower light might be happening when the batteries are low... and
now you've nailed it down. That's good to know. We've also heard
that the SR gets weak when the battery is low. So I guess the
battery life statement should say, like, "300 shots with full
performance, 400 more shots with reduced performance".

does the amount of underexposure depend on the aperture set? I was just thinking it could be that the camera is taking the reading before the aperture has completely stopped down.

Nick

Thanks Xavier - I was aware of this and I did all the tests in average and not matrix.

XavierP56 wrote:

Beware : In A Mode on the aperture ring, you can use MATRIX metering.

With M Lens (or A Lens but not on A on aperture ring),
CENTRAL-WEIGHT is used, whatever the exposure mode switch is on.

So, if you want to comapre things with a lens in A setting on the
aperture ring, please set the metering to CENTRAL-WEIGHT !!!

If not, you are comparing apples to oranges.