[bjdavey]

Yes, so long as the lens design includes an ID chip (which all the newer Pentax lenses have). It is the same ID code that is used in the EXIF data to identify the lens for software and PP lens corrections.

[geezer52]

The 1.03 update was supposed to help fix the front focussing in low light.

.... however it would make a lot of sense to recalibrate your lenses in normal light levels following an update to 1.03

Understood, but before going about the recalibration process to begin with it makes sense to me to first confirm that things like the firmware version are up to date.

[Thesorus]

First I tried various adjustments and nothing changed: Discovered you have to turn off the camera and/or take off the lens.

Do I really have to power on/off to see the result of the adjustment ?

Thanks.

Max.

[awaldram]

They all appear to need a +2 or +3 adjustment. Seems I can do a +2 for ALL, and override with +7 for my macro lens.

Hi no-one seems to have mentioned this is not a valid configuration.

+2 for ALL is just that there is no overide it you've set +2 for ALL thats what you get.

The +7 will be ignored as the manual correctly states.

if you want +2 for every lens then set them indiviually then +7 for the macro.

I wonder though as I keep reading folks using these invalid configurations just how repeatable their test methods are ??

My body is also +3 off the same as my previous body so I'm not sure if they really are +3 out or if its the 1/3-2/3 DoF setting from Pentax.

Though I prefer the +3 so have that set for every lens.

My Bigma is -3 out and is the only lens I own that requires adjustment so for this lens the camera is set @zero (or in reality not set at all)

---

Last edited by awaldram; 06-05-2011 at 11:24 PM.

[HenrikDK]

Hi no-one seems to have mentioned this is not a valid configuration.

+2 for ALL is just that there is no overide it you've set +2 for ALL thats what you get.

The +7 will be ignored as the manual correctly states.

I don't think you are right, but not 100% sure. See this thread: Multiple people claim the single lens setting will override the ALL setting.

https://www.pentaxforums.com/forums/pentax-k-5-forum/136384-apply-all-apply-o...djustment.html

Yesterday I took quite a few pictures and and focus had improved noticebly with my 55-300 at 300. Also some shots with my 50mm Macro were much better. If what you are saying is correct, I would see the benefit from the 55-300 (+2), but the Macro (+7) would still have been off. I'll re-read the manual - sometimes it can be difficult to interpret these types of "layered" rules

[Class A]

Any other guidance you can give me?

You received some good tips, but also incorrect information.

It is for instance not true that getting AF right for one distance implies that it will be correct for other distances. You'll have to optimise for a particular distance / shooting situation.

The same applies for f-ratios as lenses may show "focus shift".

My AF adjustment hints are pretty comprehensive.

P.S.: As has been said, Macro and AF don't go together well. You are better off doing manual focus. Use the focus setting to get the right framing and then gentle move forwards and backwards to get the right spot into focus. If you are using a tripod, you'll have to use the focus setting to set the focus which can be more difficult (depending on the lens).

[Class A]

if you want +2 for every lens then set them indiviually then +7 for the macro.

I don't have a camera with that capability to test it, but note that manual only says that an "Apply All" will override all individual settings.

It is quite possible that you can set a value (+2) for all lenses and then do an individual override (+7) for some, retaining the original value (+2) for the rest. That would be reasonable behaviour.

I'm assuming that there is an individual correction value for up to 20 lenses and that "Apply All" simply sets all these correction values to the same value (e.g., +2). There is no cumulative effect and individual adjustments shouldn't override other correction values. It really should be that simple.

[HenrikDK]

+2 for ALL is just that there is no overide it you've set +2 for ALL thats what you get. The +7 will be ignored as the manual correctly states.

Awaldram - you appear to be correct - at least partly: here is what the manual states in a note:

"Even when an adjustment valiue has been saved using [Apply One], if you press the OK button with [Apply All] selected in step 3, the [Apply Value] is used instead of the [Apply One] value."

This seems to confirm what Class A says: The [Apply All] probably overrides all 20 lenses (registers) with the same value, and you can then override those with [Apply Single] values.

Here is the weird thing: The camera remembers both the camera setting and the lens setting (I have my 50mm macro set at +7 and the camera at +2). The +7 does not go away when i use [Apply All]. In other words either the camera DOES indeed keep and use the +7 (and the manual is wrong), or the actual stored value is what ever you applied last, but the value is not visible anywhere?! The latter would be a real weird implementation: Why would you have two different sets of registers for the 20 lenses, and then not show the actual used one?

I got a new 35mm DA-L two days ago, and that lens show <Unset> for the lens.

The logical answer would be that there is ONE camera register, and 20 lens registers, and if the lens register is not set, the camera register is used, otherwise the lens register is used. If so the manual would be wrong.

Anyone have any idea? I guess I can start testing, but surely someone has figured this out before?

[HenrikDK]

My AF adjustment hints are pretty comprehensive.

I read through your hints, and they are indeed very comprehensive. Some of this I was somewhat aware of, but your write up certainly helped clarify. Thank you.

I think Tim jackson changed his chart, but either way I appeared to have very little problems with the focus, and over multiple shots appeared to generate fairly consistent results - +/-1 on the fine adjustments. I.e. resonably certain I should use +7 rather than +8 or +6. My ability to judge what was in focus vs out of focus, especially on the slower lenses with higher DOF, seemed a far greater limiting factor than the focus area. Another chart may make it easier to determine the in-focus areas. Guess I need to do more testing, but I do believe the relatively simple adjustments I did improved my results greatly - certainly more than I had expected.

My point is that probably any of these tests are a lot better than nothing, especially when you have a lens like my D FA 50mm that was way of at +7.

[Kerusker]

My finding (which has been approved by PENTAX support) is simple:
Look at the 'AFAdjustment' value in EXIF data of the shot - that is what was actually applied to the shot.
Read the 'all' as 'all except the lenses with individual setting'.

Will post some more about the difficulties of 'AF Fine Tune' as experienced with my K-5 and lenses.

[Kerusker]

I read through your hints, and they are indeed very comprehensive. Some of this I was somewhat aware of, but your write up certainly helped clarify. Thank you.

Class A has set up a very good set of rules, but rules don't contribute much for understanding what's going on.

My ability to judge what was in focus vs out of focus, especially on the slower lenses with higher DOF, seemed a far greater limiting factor than the focus area.

That's what I have observed also and there are some reasons for it.
Falk Lumo has set up a paper 'Low light focus accuracy with the Pentax K-5 camera' on his blog LumoLabs
Chapter 3 'General remarks regarding normal focus accuracy' does contain some of the reasons:
'In other words, focus tolerances df of up to 100 µm are normal (for non professional cameras) even if this is probably shocking news for pixel peepers '
I don't know what the adjustment value of one AF-FA increment is, but it seems to be less than the normal focus tolerance of the K-5.

' It is a pitty that Pentax didn't include at least an f/2.8 wide center AF sensor as it is needed really to exploit the K-5's high resolution. With its current phase AF accuracy, f-stop figures around f/8 to f/11 are required to bring b defocus down to about 1 px.'
Now this is an explanation why the K-5 is a pro-sumer camera and no pro-camera. It's optimized for slow consumer lenses like the kit lenses.

Till now I don't own expensive fast AF-glass and may be I never will. For me the K-5 is adequate but AF-FA is problematic.

Thanks

[RobG]

Is there a documented process for lens calibration somewhere?

[SlickYamaha]

Do I really have to power on/off to see the result of the adjustment ?

Thanks.

Max.

Is there an answer for this? I have tried to adjust, and see no results. Should I power cycle each time? Change out the lens?

[txborn]

Just finished experimenting with the FA 31mm Limited. Tried AF Fine adjustments from 0 to +6 and saw no difference. Used several different focus distances. Focus acceptable between F5.6 and F11; any other value looks out of focus at 100%. I had a Sony Cyber Shot that images still looked reasonable at 200%.

So there are 11 focus points on this camera but I have only seen one red dot, usually in the center when I depress shutter half way. Is this normal? I'm set to Auto AF/11 points. Other cameras I have used in the past would show multiple focus points when pressing the sutter half way. Am I missing something?

On a different note, the DA 18 - 135mm shots look great at 100% and very reasonable at 200%.

[Eruditass]

Use this method:
autofocus - What is the best way to micro-adjust a lens? - Photography - Stack Exchange