Please help! "New" used K-X hast BF-problem - Debug mode?

[babha]

My second post here.

Last week the used but almost new looking K-X plus 18-55 were delivered.

Not expecting too much from the kit-lens, I also got a DA 18-135 WR and DA 1,8/50.

DA 55-300 and Tamron SP 17-50 2,8 came on saturday.

Although we experience a real November, gray and gray almost every day around the clock, I was excited to take first pictures.

And was shocked to find out, that it looks like there is more or less some amount of BF in most images. First I thought, I perhaps had expected to much of the 18-135 ... but unfortunately it wasn't just this lens.

Very strange though, if I take pictures inside of an open book, at different distances and zoom-settings, most of the results are tack-sharp!

Outside it's quite the opposite. For instance I take the picture of a tree, focussing at the trunk, the leaves a bit behind will be in focus - the trunk itself will be soft.

I did a lot of research before I decided for getting the K-X. Strange enough I haven't found what seems quite common with this camera. Focussing is just so-so. Not extremely reliable. Perhaps the focus-point is just too big.

I use back button focus, shutter button will not focus, only the focus point in the middle is enabled, AE is disconnected from focussing. I use AF-C for this method, but just to explore I tried AF-S too. No difference.

Reading the forums I found out, it's only possible to correct focussing for ALL lenses, so only one setting is possible, plus it is necessary to enter "debug mode".

But here comes the thing: I don't understand what exactly to write into the root directory of the SD card.

Yes, I found the very helpful site https://ricehigh.blogspot.com/2010/01/k-x-debug-mode-tutorial-af-adjustment.html where there is a good explanation.

But "if you don't know how to create the file, simply download here ..." just doesn`t work anymore. The page was published 2010, when K-X was pretty new.

What can I do?

These days it hasn't been clear, if it was only possible to enter debug mode having firmware 1.0.

The latest firmware is 1.03, which is on my K-X. So perhaps I am out of the game anyway?

Just forget the K-X and move on to K5 for example?

 

[robbo d]

I bought a new kx in 2010 with no problems, sold that and now have 5 different coloured Kx... yes 5.

No back focus issues on any of them...

My current thread was using sports ( auto af-c) and landscape mode (af-s)

Using sports mode with af-c the focus point occasionally picked up someone in the background.... yes the af point is probably quite large.

With ANY fixed or stationary subject like landscapes, buildings or portrait I use af-s.

It is an inherent problem of the af point not being visible, an entry level camera that the Kx may pick up the odd strange focus point but:

I also took a tree trunk image with some vines growing, using landscapes mode at close range and it was tack sharp.

Maybe if you show us your images, then we may comment with better hindsight.

I find that while the technology is now old and the AF system would now be considered archaic that my recent triathlon sport shoot was 90+ % successful regards AF.

It may be your camera but as I said above, show us your images first.

Yes, k5iis and k3 would be an upgrade. Images from the k5iis were the ultimate from that superb 16mp sensor without the AA filter and AF points with directional change will help plus K5iis I believe can micro adjust for different lenses

 

[flektogon]

O.K., shoot with the other lenses to see, if they backfocus as well. But I doubt that there is a problem with the camera/lens if it focuses correctly indoor. Are you using just the one, central AF point? And is the subject "of interest" in the centre? You know, as the K-x camera doesn't show where it focuses, setting (and using!) the central AF point is the safest way.

Now, if the user's errors are eliminated, concentrate on the camera. Do you know that the K-x cameras suffer from the "mirror slap" problems? It's happening at the shutter speeds between 1/80 up to 1/160. The pictures very often turn to be soft/shaken. But this will be seen across the entire frame.

My K-x camera behaves weirdly regarding the auto focusing as well. It really BF, but I see it only with my DA 16-45/4 lens. It AFs perfectly when zoomed out (45mm), but as I start to zoom in, it starts BF. At the 16mm setting almost twice. I mean that if 45mm setting focuses at a subject 2m away correctly, when I zoom in to 16mm, and refocus, the lens ends up at the 4m distance. O.K.potentially there might be a dirt on the PDAF sensor! I am not sure how "dirty" your camera is, but if there is (was) a lot of dirt on the main sensor, this PDAF sensor could be dirty as well. You can try to blow out the dirt from both sensors with a dedicated blower. But you have to be careful, if not very skilled, leave it to clean to a specialist.

--
Regards,
Peter

 

[babha]

Thanx to Robbo and Peter ,

highly appreciated and interesting answers.

Sorry for coming back after quite some time - but I was knocked out by heavy cold foe a couple of days and still not completely back to 100 %.

I will post some examples soon.

By going through these first images I have to admit that I am perhaps a bit picky.

On the other hand I honestly have never experienced something like this - even if I have a go for dated gear.

I do use the center AF point only and focus by pressing the AE/AF button ... shutter button AF is deactivated.

More or less this is how I work with all my cameras.

A few days ago I got a really great offer of a used K5ii, I couldn't resist - even if this wasn't my plan.

Really wanted to like the K-X and did if it came to shape and size of the body.

So far though I haven't done much more than to chase an in focus image.

I expect my experience to be better using the K5ii in a couple of days when it will be delivered. Weather Protection will be just one highly appreciated plus under actual weather circumstances.

Well, size and weight will be more, that's a downside I will have to cope with.

Not much of a difference to my Canon 5D classic I just sold, because the whole package wasn't fun to lug around for many hours.

At least the lenses for Pentax I have so far are significantly smaller and lighter than the FF EF-lenses (only exception of course: the really tiny and great 2,8/40 stm pancake)

But I will not give up on K-X either ... see if I can make it behave to my liking.

It still looks like new, just 11.000 actuations. So it has deserved to be used much more

 

[babha]

All are converted from PEF using Raw Therapee. I have to admit though, I haven't found the "perfect" settings so far ... jpegs come out with more detail but pretty "grainy". I am posting them anyway, as the oof-areas are easily visible.

Just yesterday evening I downloaded Pentax DCU 5 and did a few first trials. Not disappointed so far. My experience using silkypix products is pretty limited though.

I gave up on Adobe products after they changed to their abo system. LR 4.5 was the last version I used on my Thinpad these days when it still worked.

Raw Therapee has become much more complex, and complicated I would call it, in it's newer versions.

It used to be my converter to go in the old days, when my pre pentium Notebook took a whopping 10-15 minutes !! "run" to develop any Raw File from my first digital, Fuji S9600

Not to mention that the Fuji used 6 seconds to record each file to it's CF card. Without buffer

At least made me really be patient for "THE moment" and use the shutter button carefully ... just like in the old film days.

Well ...



hardly anything really "sharp"



focus was on the front wall ... side wall seems to be IF



hardly anything sharp



the first day, focus point middle tree, not really sharp



live view, sharp exactly where I wanted it (about the center)



once in a while perfect: trunk as sharp as focused

I set to Auto-ISO. Wasn't aware though that lowest ISO is 400 if not expanded (making it to 200). Light was poor in all shots, very cloudy, grey, with rain occasionally.

--
my pictures: http://www.flickr.com/photos/batuk_bhagwan/

 

[flektogon]

Actually very nice pictures. Definitely no problem with the BF, or any other focusing problem. What I see is a little bit of noise. Pity that your EXIF doesn't show applied ISO setting. Why is it so? Btw. the minimum ISO is 200, after expansion it goes to 100. Keep it expanded as you need it if you have the Highlight Correction enabled. And enable it, it is helpful, even when shooting RAW.

Here is one of my typical pictures. It shows ISO 200, what in such a sunny situation means that the highlight correction has been engaged.



--
Regards,
Peter

 

[RiceHigh 22]

Hi, just drop me an email and I shall send you the debug file that you need.

 

[babha]

That would be great

I sent you a pm ...

Thank you!