more about K10D Debug Mode

[no see]

excuse me, if some of the following details are old stuff. I searched the threads and blogs and found many valuable hints - thanks.

Short introduction:

I have used analog Pentax gear since my first SLR (Spotmatic), then LX and Super A. I switched to digital early with some Olympus 1.3 MP cam up to the Camedia 5050. Then I switched to Panasonic (FZ30, FZ50, TZ1, TZ5).

I've tried a Pentax *ist D about 2004, but could't get sharp focus with my old K-lenses - so I gave it back. In Nov. last year I bought a used K10D and learnt, that there are still focus problems with DSLRs.

My K10D had severe BF problems, which where mostly fixed by Pentax service (under warranty). Then I tried the SMC 50mm 1.4 prime and found, that it has bad BF. The general tendency is: My DA lenses have slight FF and my manual lenses have slight to bad BF.

Two days ago I have switched on the Debug Mode' on my K10D for the first time(engl. version of the russian prgr).

Surprise: All four focus correction values were zero (after the BF fix by Pentax).

Then I wanted to know: does the focus correction offset the sensor distance to the lens?

The 50mm at 1.4 was mounted, K10D on tripoid, man focus, SR off, cable release. Then the K10D was visually focussed and focus was not touched during the following test:

2 shots with 0um, in Debug Mode settinng to -100um then 2 shots, in Debug Mode setting to +100um again 2 shots. Result: All shots show exactly the same sharpness resp. sharpness area.

Conclusion: The focus correction does not influence the sensor position! I.e. no correction for manual lenses.
Then it must be an offset for the SAFOX.

Another observation (I didn't find elsewhere till now):

In Debug Mode you can select the strength of SR for manual lenses in the menu for focal length selection after switch on. Strength can be selected between '- , normal, +'.

Next I will try to improve visual focussing for my manual lenses regarding possible screen and sensor distance difference.

Any hints and critics are welcome. Thanks for reading.

--
no see (resp. ][.Kerusker)
we don't see that we don't see (eye's blind spot)



my albums: http://picasaweb.google.de/Kerusker

 

[MikeChip]

Bookmarked

Mike

 

[il_alexk]

Pentax service doesn't use the Debug mode to correct focusing issues. You may find more information on what Pentax (or Samsung) is doing in the GX10 Technical Service Manual.

http://forums.dpreview.com/forums/read.asp?forum=1036&message=27877338

--
Cheers,
Alex

 

[no see]

Pentax service doesn't use the Debug mode to correct focusing issues.
You may find more information on what Pentax (or Samsung) is doing in
the GX10 Technical Service Manual.

http://forums.dpreview.com/forums/read.asp?forum=1036&message=27877338

Alex,
thanks a lot for the link.

I scrolled through the manual - very interesting (although there's a lot of adjustment software handling and setup, which doesn't explain much to me).

Most interesting is the 'AF shift adjustment' (pages 119-121). But again, I'm not shure what it does. It's very similar to the 'Focus correction' of thee K10D 'Debug Mode'.
The wording in the manual is strange:
--snip--
3-4. AF shift adjustment
＊This chapter is for checking the Focus in the A/S center.
＊After taking a picture, you can check the focus position synthetically.
＊You can apply this adjustment to each lenses.
....

• You can't improve the focus with this adjustment even though there are no reasons, do the Focus adjustment

--snip--
The most enthusiastic way to read this would be:

"You can't improve the focussing of the body with AF shift adjustm., but you can adjust the focussing of each lens (beeing capable of AF shift adjustment)."

Please help - there are some members on this forum which should know (payd by Pentax, but not for beeing a member of this forum

--
no see (resp. ][.Kerusker)
we don't see that we don't see (eye's blind spot)



my albums: http://picasaweb.google.de/Kerusker