[wombat2go]

Old thread. The ist ds had the AF trim available in the firmware, a slider in the DeBug mode.
Only one adjustment for the body, not for individual lenses.
However 2 lenses tested both needed the same setting
I used a 1 metre long carpenter's straightedge and sat a focus hash at 500 mm
One well used body needed to be set - 80 um, a newer one was OK at 0.
The tricky bit is the slider reverts to 0 after the adjustment is saved.
I am about to take the sensor out of a broken ist ds, mabe make one good
body out of 2, so the adjustment will be needed if I get that far.
(The sensor and the dsp/cpu board have to stay together)

[gp1806]

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[savcom]

Well, I had a go yesterday morning at adjusting the focus. I have a Pentax DA 18-250mm lens which came with the camera but have not been entirely happy with shots taken with the lens wide open. It always struck me that the focal point was just in front of the subject rather than at the centre of the object.

So I set up three pencils and a plastic ruler on the kitchen worktop and, with the camera on a tripod, I went to work. All shots were taken by manually setting the focus to be as close as possible, and then auto-focussing to take the shot. This way, focus is not the same each time but relies on the camera having to re-focus on the same spot before taking the picture (Highly scientific, but there we are.)

The first picture shows the focus set without adjustment:


The focal point here was the tip of the central pencil. However, the shot shows that the focal point of the shot is actually set around 5.6" rather than 6" (the pencil tip).

I adjusted the AF setting by -50um and took another photo:


This time the focal point does seem to be at the 6" mark and ruler markings between 6" and 7" do appear sharper (especially when the two photos are viewed side-by-side)

So this has made a discernable difference, so may I add my thanks to the others here for your work setting up the guide.

Interestingly I tried two of my other zooms and noticed that my Pentax-F 35-135mm zoom looks decidedly soft in comparison. Here are the three pencils in Macro mode:


And here is the same picture through the DA 18-250mm set at 250mm:


Much better. And both were focussed the same way.

I've not had a chance to play outside as the batteries decided to die on me during this work, but I have got one photo from this afternoon that shows that focus looks about right....



Thanks again. Well worth the time and effort.

Cheers

Savcom

[Adam]

This should probably be re-formatted and then posted in the articles section!

Adam
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[savcom]

This should probably be re-formatted and then posted in the articles section!

Happy to help - I'll take a look over the weekend and see if there are any guidelines I should follow. Is the OP happy with this?

[kmac1036]

I'm in desperate need of help. my firmware is 1.01 & cannot get debug mode to work, only displays my firmware version for a few secs then screen goes dark. I have a back focus issue. PLEASE HELP! I need my camera, just started a new job, can't afford a new camera right now :-(

[cbaytan]

I'm in desperate need of help. my firmware is 1.01 & cannot get debug mode to work, only displays my firmware version for a few secs then screen goes dark. I have a back focus issue. PLEASE HELP! I need my camera, just started a new job, can't afford a new camera right now :-(

Try pk_tether it takes camera to debug mode with one click on and off without messing with text file to memory card or anything, but since my camera stil has FW 1.00 please let us know if it worked out for you too.

PK_Tether | Tethering and remote control software for Pentax DSLR cameras

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Last edited by cbaytan; 01-21-2012 at 06:58 PM.

[kmac1036]

just tried it, didn't work either. all of this got squelched in the firmware update works on the K7 I bit the bullet on & picked up today. $820 OTD with 3 yr pentax extended warranty. couldn't pass it up.

[Jonathan Mac]

just tried it, didn't work either. all of this got squelched in the firmware update works on the K7 I bit the bullet on & picked up today. $820 OTD with 3 yr pentax extended warranty. couldn't pass it up.

The focus adjust is still there in firmware 1.01, and accessed in exactly the same way. Why don't you tell us exactly which instructions you're using and we can spot where you're going wrong?

[kmac1036]

took one more look at it. put a [CR] in it to make sure it was registering the line return I checked the file info (under OS X. tried this on Win 7 too, both actually were appending the .txt on the file!!!). once I opened the Get Info pane (same as right click > Properties on Win), I deleted the .txt from the filename & the icon changed... debug popped right up! I even tried the PK Tether, it has a button that enables/disables the debug menu but it wasn't seeing my camera. used the AF adjust, needed a +70 to get it back close. I also had a problem a couple weeks ago: it froze up to the point I had to pull the batteries.
wish I'd figured this out sooner, but I really like the K7. Having a really hard time parting with it.
thanks for the help!!!!!

[cbaytan]

OS X !! I would try once more with pk-tether on a 32 bit windoze, mine is Win XP x64. My steps just in case=

-I connect the cam off with USB without turning on.
-I open pk-tether
-I turn on K200D,
-pk tether sees the camera
-just one click to debug mode off, that all,
-disconnect from pk tether, wait for discconnection
-disconnect from USB
-turn off cam
-turn on cam -- ta-daa.

[mconwxdr]

Old post, but just wanted to pass along a thank you. I've had my K200D for almost three years now and I had no idea this was possible. I just dealt with inaccurate focus all that time. I just bought a DA70 and it was backfocusing pretty bad. A +100 adjustment did the trick (I just had to make sure I removed the ".txt" from the file that OSX automatically appended to it). Thanks again!

[Jonathan Mac]

Yes, it's a bit tricky getting it right and removing the .txt isn't mentioned anywhere in the instructions I used.

Really, all DSLRs should have a system for proper AF adjustment for at least a dozen lenses as a basic feature. DSLRs are more sensitive to focus errors than film cameras, or at least we're more aware of them due to the ability to pixel-peep.

[nutkasse]

hi all, i also have a k200d & i have windows 7 pro. i don't have a "new" when i right click on the sd card. i have a "open in new window".is it the same thing??

[savcom]

hi all, i also have a k200d & i have windows 7 pro. i don't have a "new" when i right click on the sd card. i have a "open in new window".is it the same thing??

Hi Nutkasse.

No, unfortunately this is not the same thing. Open in new window lets you browse the contents of the SD card in a new explorer window.

I suspect you're clicking on the SD card in the My Computer view.


Try double-clicking this and then try right-click then New...


Let me know if this helps.

SavCom