Focus Correction on Pentax K-x

[Monkeytail]

Hi Pentaxians,

I was wondering if anyone using a K-x may have experience taking pictures which are never sharp focus?

This is especially obvious when using a shallower DOF (eg, f1.7, using tripod and spot focus).
I finally realise this after a few months of fustration not getting sharp photos from credible lens like F-50mm f1.7 and Tamron 17-50mm f2.8 SP.

After doing the debug (refer to the below link) with adjustment to +160um, I am finally getting sharp pictures from my F-50mm.

http://www.clubsnap.com/forums/showthread.php?p=6117456


I hope this information may be helpful to the newer k-x owners.
(Note : Only do this if you are comfortable with the debuging process.)


Cheers!

 

[airconvent]

Hi Monkeytail
Thanks for sharing again. Is this a global setting or need to be done for individual lenses. How do you test the result systematically (as opposed to looking at your photos) ?
Regards

 

[orlyandico]

I think the focus correction on the K-x is exactly the same as that in the K10 -- it is a global setting. Which means if you're corrected for one lens, all the rest of your lenses will be out. It's one reason I upgraded from a K10D to a K20D! one of my lenses (16-45) needed a huge amount of correction, which screwed up the rest of my lenses.

 

[Monkeytail]

Hi airconvent,

I can see the sharpness difference on f1.7 and f2.8 setting with this adjustment. It improved on 2 autofocus lens which I tried. (The F-50 f1.7 and Tamron 17-50 f2.8)

(FYI, i mount the k-x on tripod using high ISO to eliminate camera shake, didn't care about the noise. I was focusing on a silvery philip-screw on my black speaker, this may not be a "proper" test, but I can lock focus easily and check sharpness looking at the "+" of the philip-screw.)

However, using my kit lens 55-300mm f4 setting, I cannot tell much of a difference between +0 um or +160um setting anymore.


I am writing this thread to seek others who may have similar experience the same as me.

BTW, I am not sure how it will affect manual focus lens.


Best Regards
Monkeytail

 

[macrob]

I think the focus correction on the K-x is exactly the same as that in the K10 -- it is a global setting. Which means if you're corrected for one lens, all the rest of your lenses will be out. It's one reason I upgraded from a K10D to a K20D! one of my lenses (16-45) needed a huge amount of correction, which screwed up the rest of my lenses.

I doubt that.
Maybe I am out for a while, did not notice the news, but from what I have learnt before, K10D and K-x can remember the individual adjustment for 4 lens.

I have been doing this for 16-45 and 50-135 on K10d, also s70-200 and 43ltd on k-x. So far no problem.

 

[flowerpot]

K-x can do up to 4 lenses.. ?

 

[tsammyc]

I noticed my KX is a bit off with my FA31, but is fine with the rest of the lenses. My K5 seems spot on with the same FA31

 

[seafone]

K-x can do up to 4 lenses.. ?

Er, can any bro confirm this?
Or is it a global setting adjustment? I thought it's global.

After using k5, I notice that some of my lenses somehow need some adjustment.

 

[macrob]

K-x can do up to 4 lenses.. ?

I am not sure about this also, I have heard it since the K10D era.

From my own experience, I can not confirm whether its global setting or not.

But, it seems all the adjustments of every individual lens works well so far..

 

[ramukavis]

I too would like my K-x to have more than one adjustment, but AFAIK, it is global (applicable to all lenses).
BTW, any one knows what is the 'AF Area Test' and 'AF Area Number' mean?

 

[orlyandico]

K10D cannot do 4 lenses, I'm 100% sure of that.

 

[timo]

K10D cannot do 4 lenses, I'm 100% sure of that.

Actually I think it can (more than 4, IIRC), but it has to be done the official way by the service guy.

The unofficial hack is a global adjustment, you're right.

Tim

 

[clownpo09]

Actually I think it can (more than 4, IIRC), but it has to be done the official way by the service guy.

The unofficial hack is a global adjustment, you're right.

Tim

have you tried it? who are these service guys that you are refering to?

 

[banana0ne]

have you tried it? who are these service guys that you are refering to?

Just send the camera to emjay...

 

[clownpo09]

Just send the camera to emjay...

ah ok. that settles it

 

[orlyandico]

hm. If I had known...! I wouldn't have gotten a K20D! which is slower than the K10D.

Oh well...

 

[felixcat8888]

I think the focus correction on the K-x is exactly the same as that in the K10 -- it is a global setting. Which means if you're corrected for one lens, all the rest of your lenses will be out. It's one reason I upgraded from a K10D to a K20D! one of my lenses (16-45) needed a huge amount of correction, which screwed up the rest of my lenses.

The K20D can correct more than 1 lens. Think it is up to 20 IIRC. The K20D is much better than the K10D though . . .