[luma]

I have been playing with my new K-S2 trying to set the best AF fine adjustment for my half a dozen of AF lenses. What I have noticed, there is much better sharpness looking at LCD in Live View compared to actual recorded picture from play back. It is most noticeable when zooming in to maximum (16x) in both Live View and play back. I have noticed the same thing with my other, K-50 body. I did try to disable some of the on camera picture processing/correction features but nothing makes a difference? I would assume, if a lens itself was a culprit, it would affect Live View as well?
Has anyone else noticed this, could you comment?

[Adam]

16x is overzoom, so the image will never be perfectly sharp at that magnification. I believe live view zoom caps out at a lesser degree of magnification, hence the difference.

Around 8x should be 100%.

[luma]

16x is overzoom, so the image will never be perfectly sharp at that magnification. I believe live view zoom caps out at a lesser degree of magnification, hence the difference.

Around 8x should be 100%.

I am pretty sure that even at 8x magnification on both recorded playback and live view, the live view is much sharper...

[luma]

So I have found, in my opinion, fairly accurate, efficient and quick method to do AF Fine Adjustment for my Pentax lenses. It is a slight variation of a method I found on dpreview.com, here it goes:

Find on the web one of those camera/lens test charts, preferably the bar graph type that has a various scale resolution patterns (I used the one attached). Use the highest resolution JPEG or PDF you can find and print it landscape on letter size paper. Tape the chart to wall or door, same level as your camera on a tripod, in a well lit space. I used distance about 5 feet between camera and chart, but feel free to experiment, depending on your lenses. On camere, I used AV mode and fixed ISO 200 for all measurements.

1. Go to menu with AF Fine Adjustment and check what is your current setting. Go to ‘Apply one’ and start with initial setting 0.
2. Set lens zoom in the middle (say 35mm), open the aperture fully (lowest number) and manually put lens out of focus (say infinity). Switch the camera to AF mode and autofocus with viewfinder.
3. Turn on the Live View, hit OK and with the rear E-dial set magnification/zoom to maximum (10x). Take a mental or paper note of the LCD picture sharpness (here a defined resolution on the chart comes handy).
4. Hit OK again to step out of the zoom and autofocus again this time in Live View (either shutter release half way or AF/AE-L button). This is the correct/best focus the camera can obtain while in Live View.
5. Hit the OK again to get the magnified detail on the LCD. If the picture sharpness is about the same as per 3., your viewfinder AF is working correctly and you are done for this particular lens.
6. If the LCD picture sharpness in 5 is better than in 3 (most often the case), you have to start experimenting with the AF Fine Adjustment setting. Go back to item 1 and adjust setting tentatively by about +3 and then follow items 2 to 5. If you improved the viewfinder autofocus sharpness, your setting is in a right direction, otherwise you have to go in opposite direction.
7. Try different settings, interpolate, until your viewfinder autofocus is as good as the Live View autofocus. Repeat for all your AF lenses.

I strongly suggest to do the AF Fine Adjustments for all your lenses, you will be surprised by the results. For illustration, here are results for some of my lenses:
The kit lens DAL 18-50mm DC WR RE required the maximum +10 points adjustment. The DA 35mm AL required +7 points, the DA 18-135mm ED AL DC WR +2 points, while the DA Fish Eye 10-17mm ED required 0 setting.
On my K-50 body the settings for the same lenses were different. BTW, this method works much better with K-S2 than K-50 due to sensor resolution. As well, with K-50 you need to be in M focus mode to get the Live View zoom, with K-S2 it works in both M and AF focus modes.

Attached Images

 

[SnapperDaddy]

So I have found, in my opinion, fairly accurate, efficient and quick method to do AF Fine Adjustment for my Pentax lenses. . . .

Thanks for this, I will try it after my newly purchased K-S2 arrives tomorrow.

My 1980-vintage builder-grade house isn't from the set of The Cabinet of Dr. Caligari, but I don't think I have a level floor or a true vertical wall in it, so I must pursue leveling both the chart and the camera. Using a bubble level with the camera would be easy. I'll have to think about verifying that the chart is level and on a flat plane.

But, wait, I have a better idea: the easy means of guaranteeing the correctness of the angle between camera and chart would be to use a copy stand. Since I have a K-S2 with a flippy rear LCD, I could borrow the stand from work, mount the camera upon it, then adjust the camera's rear LCD to allow me to work without needing to position myself above the stand or impaling myself upon it.

I gather that control of the K-S2 via Wi-Fi is less than wonderful, but I might try that, too; exploring the Wi-Fi control with a fixed subject would be a test of the camera without time pressure. . . .