K-5 1.03 versus K20D AF tests

OK folks, here's today's tests between K20D and K-5 V1.03. I tested both cameras both my FA50/1.4 and Sigma 30.1,4. Aperture for all tests was F/1.4. I first tested in daylight, around

EV9 and made sure the AF for both lens was properly calibrated on Both cameras. Interesting to note that I needed to recalibrated both lenses on the K-5 following the V1.03 update. I also tested in brightish tungsten ( around EV6.5)

The three lower light tests were done in a dim room with natural light, with a combination of tungsten light and the computer monitor, and with a combination of tungsten light and the

light from the little portable TV on in the background. Hopefully covering a range of common scenarios. Everything was exported from RAW with absolutely no PP whatsoever.

The last test had each lens and camera focussing on the Phones 1 jack plug of my Studio monitor controller. The K20D/Fa50 nails it at EV0.5, but the K20D/Sigma30 back focusses. K-5 FF's with each lens.

Some may remember I posted a test between the K-5's Contrast live view AF and the regular phase AF by shooting a car license plate ( FW1.02). I repeated that tonight with the K-5 FW1.03. unfortunately no better. I'll post the pics later. Hope these tests help .




First the Pentax FA50/1.4 lens wide open at 1.4
























Second the Sigma 30mm/1.4 lens wide open at 1.4
















With both lenses at EV1.5 in the room with tungsten/computer monitor light the K20D nails it and the K-5 severely front focusses. The Sigma on the K-5 slightly Front focusses in natural light at EV1.5

Interesting. What I would do with this is to use QuickShift to make the slight adjustment in these circumstances. Of course this is only possible with DA lenses, but for those who do use those lenses it would solve the problem.

A final test with a DA lens would be interesting to see if thesre is also a problem there.

However, in real world photography it will dpend on what a photographer shoots as to whether it's a problem at all, or not. In the photography I do I would never come across this as an issue.

Heavens...

It's not a solution. It is a workaround.

And it's a rubbish workaround if the subject is moving and not giving you time to mess about with QS.

And if your eyesight is so good that you can QS accurately, reliably and quickly enough - down at EV 1.5 - then you're a better man than most of us that believe that a thousand pound camera should work.

Honestly, John, I know you're a Pentax fan, but to be so indifferent to this problem suggests an almost other-worldly attitude to expensive technology.

It might sound strange but how does it preform with a slower lens?

I intend to try the same test with my DA* 50-135 Stephan. but not tonight. I'm all tested out.

Good question Stefan, and of course we don't have a result for a DA lens yet either.

It would be ironic if it were to be spot on with the kit lens...which is possible because other photographers don't have a problem. I wonder what lenses they use?

EDIT: It will be interesting to see thew results from the 50-135mm. Come on Smeggypants, it's only coming up to mignight!

Manual focussing is certainly NOT a solution to a faulty £1000 camera!!

I'm a Pentax fan but in the real world my K-5 is not performing to spec and my next step is to talk to Chris@SRS about getting a replacement. I waited very patiently for the Firmware fix as I didn't want to waste mine and SRS's time when the FW could have fixed it.

So while some copies of the K-5 have been fixed by this FW update mine has not.

If true that the firmware update fixes some K-5s but not others, that would suggest there's more wrong with it than just the firmware, and the firmware update is merely compensating for some physical flaw that affects different K-5s to varying degrees.

I haven't tested the focussing on mine 'properly' yet but this has convinced me to do it this weekend.

I did do some informal testing using an 'ad-hoc focussing chart' (stripy wallpaper :lol and they seemed to come out okay.

Are you sure you're not ballsing the whole thing up in the first place by 'recalibrating' your lenses.

Seems like a huge opportunity to bias your tests to me. A little knowledge is a dangerous thing and all that.

I'm not sure what to make of this post.....


Firstly it makes perfect sense when installing a firmware update that makes changes to the AF system to make sure the calibration of the lenses is still correct. As it happened they were not.


"opportunity to bias my tests? Are you suggesting I'm deliberately posting tests to show a problem when there isn't one?


And what do yo mean by 'a little knowledge' ? Seems an uncalled for assumption on the level of my knowledge there don't you think?

Hmmm??

Hey Smeggy, been following you and your "K5 story" for a while now though I've not said much, here and at the other forum. Just wanted to say I really feel for you and I'm really gutted that this FW update doesn't seem to have fixed yours.

Pentax is lucky to have users like you still devoted to their system despite the stain, FF issues, and their (IMHO) poor handling of both.

IMO i think you should contact your dealer (think it was SRS?) and see if you can arrange a replacement.

Hope that you'll be able to find a fix soon.

Best wishes

Easy Graham, having followed Smeggy's K5 story and previous tests (though I've not commented much), I can assure you he has no bad intentions and know's how to go about testing neutrally.

From what I've seen here and in other forums, that some cameras are fixed completely and some not, it's looking more likely that hardware quality variances are the culprit here.

Hope pentax sorts all the quality issues out once and for all, and ASAP.

Thanks Vince

I've held off getting a replacement as I didn't want to waste SRS's and my time if the FW was going to fix the fault. Certainly looks like I've got a defective copy in the AF department. I shall contact SRS on Monday and see what the score is.

I'm waiting to buy a 2nd body as well, but have to sell some stuff to fund that at the moment

Very thoughtful of you.

I have every confidence that SRS will be able to help you, they've always been very polite and helpful to me in the past.

Back in Jan, when i bought my K5, i had to wait 3weeks due to short supply, completely not SRS's fault. But i desperately needed a camera by Sat 29th Jan, so they offered to lend me another Pentax FREE (less shipping). Luckily they received stocks on thurs 27th and then upgraded my standard delivery to next day before 9am FREE! Talk about top quality service, you won't get that elsewhere.

Smeggy, unfortunately the tests I did last night with my fast lens showed a similar FF still. I think not as pronounced but still there. LV however will still nail it spot on.

Let me know (by PM if necessary) how your discussions with Chris go.