Thanks John.
David's suggestions above are excellent. I too wondered if the wall shots could be a bit sharper, so worth checking that.

John K

I doubt anyone uses it, it doesn't work (which is actually a shame!)

When it comes to the K-5 Horizon correction feature, it might have helped if Pentax had tried some hand held test shots to make sure that works properly, and provide an adjustment for when it doesn't. I believe most users just turn that feature off.

John K

Sorry John, I'll have to beg to differ. We take a photo of something and the AF is missing the correct focus point. We just make a simple quick adjust so that it does it correctly! It can be reset right afterwards as quickly as changing any other menu setting. To solve the issue in the field we would have to use a rough and ready solution as we do not carry round test equipment, charts, rulers or even tripods to set up to do it precisely. If a hand held solution works, why make it more complicated.

If someone wishes to adjust it scientifically then I have no issue with that, but that might not help in another lighting condition, remember the front/back focus issue when used in say, tungsten lighting which was a reported problem some had with the early firmware on the K-5.

What isn't stated is what the increments represent and there appears to be no formal guidance on the subject.

I wish to point out that I've only ever found the need to adjust that one particular lens. Others may benefit I suppose but I haven't had an issue with them.

John K

Just to go back to that software solution. If it doesn't have a dedicated Pentax output, it would still need a trial and error method to determine what actual adjustment is needed unless I'm missing something.

Mostly many put up without making any adjustments to their lenses, if indeed it is provided for in the camera settings. So if an error is suspected it only needs one to determine if it is front or back and experiment. Say put it half way to + or - 5 and see what effect that has had. If it has gone too far, bring it back a bit. If not enough go a bit further. It's the real world results that matter, not those obtained from calibration charts/software designed for other camera systems. If another time it seems wrong it can easily be reset and start again, it could be something changes with the camera so the adjustment needed might change in other conditions. Remember, with the K-5, the change can be made to just the suspect lens (though a universal adjustment is available.)

John K

John, some of my macro shots were missing the point of focus, like the stamens in a bloom and similar. By experimenting with the settings I worked out which setting put the matter right (by using that newspaper and the wordsearch.) Re-taking them after the adjustment they were much better, indeed spot on. I hear what you are saying but it isn't rocket science; it really isn't difficult to see whether the focus point is right or not. I cannot see how would your method would come up with a different result, it is either OK or it isn't.

John K

They were just two of a number of real world hand held shots taken over 10 minutes or so because I suspected back focusing. On others in between I dialled it in the wrong way and made it worse! It appears cured now.

Double checked the adjustment with a wordsearch on the back of a cornflake packet.

John K

Just a thought. If the previous owner was using it on an early pre SDM Pentax it could appear faulty to them?

I haven't got one so not sure if it is screw drive compatible but I've presumed it isn't.

John K

Focus point was the letter 'H' in the word 'However'

John K

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