K20D Banding Problem. Help Please

My K20D has the same vertical banding problem which has been discussed in another thread. It went for repair (circuit adjustment and firmware upgrade) but it came back with the same problem, so it's going back again.

Would some kind soul be willing to send me an unaffected K20D PEF file please so I can compare it with mine? Preferably something with a bit of light and shade. I can't tell whether the banding problem affects only certain shots or whether it introduces noise to all shots but is more pronounced in certain ones. There don't seem to be any unique conditions under which the problem is created. It would therefore help to see what a trouble free file looks like.

Thanks. I can PM with my e mail address.

I found one shot with banding in amongst a sequence of identical shots, it was most noticeable in an area of blue sky. It was immediately noticeable on the LCD. On a computer screen I had to zoom into 100% to see it.

Is it happening on every shot? I've taken 300 or so shots since it came back and the problen hasn't reappeared. Can you post a '100 %' crop that we can see?

Here's one. It doesn't happen on every shot. But it happens a lot - sometimes 10% or more. I can take one shot without banding and an identical subsequent shot with banding.

[IMG]http://i136.photobucket.com/albums/q185/adrianpmills/IMGP1384.jpg[/IMG]

That's pretty similar to what I got, the repair consisted of re-programming the camera which doesn't tell you very much. I suppose all you can do is send it back with a print and ask them to sort it properly. At least in my case the turnaround was very fast and the camera was back within a week.

Yupp, very similar to what I had. The service changed the sensor, if I remember correctly. It did help a lot to rectify the problem, though I had a re-occurrence in a shot recently.
The service was pretty quick, so it really is worth it.

Good luck,
Prieni

I sent it back once, together with a printout of the forum discussion here which lead mostly to sensor replacements and lots of samples. Slightly awkward for me as I live in France so I have to find someone to take it back to the UK then to Pentax then back to someone in UK then back to me. Can take ages.

Would someone be kind enough to send me a PEF file please so I can see what one should look like?

But Pentax have an international warranty. Any jpegs I have posted here look exactly like the PEFs. If you have shots without banding that is what they should look like but go here for a PEF of mine: link This may take rather a long time to download.

If you live in France you only deal with any customer services department as absolutely a last resort.

I can't open your link I'm afraid. My jpegs look quite different from my PEF's. In my Jpegs I can see individual pixels. In my PEF's I can identify larger squares each one containing 64 pixels, I think.

It might have something to do with your RAW program so what RAW program are you using and which version?

Looks to me like there is a hardware problem.

Meanwhile, you could try Silkypix Developer Studio. One of its noise reduction functions is designed to remove banding.

I'm using the software bundled with the camera which is Pentax Photolab 3.5 (based on Silkypix I believe). I can't afford Silkypix Developer Studio at the moment.

I'm convinced there is a hardware problem too. Other cameras with the same problem as mine have had their sensors replaced.

Yeah I heard something about the hardware before... no idea what the problem was though.
Could it be the video card maybe?

It might - I'm going to buy another one tomorrow on the offchance. But the banding is identical to that experienced by others here therefore most likely not.

Here's what my PEF file (one without vertical banding) looks like in Photolab. It would be good to hear that this is normal:

[IMG]http://i136.photobucket.com/albums/q185/adrianpmills/PEFExtract.jpg[/IMG]

your last photo is no banding though, here compare them.
https://www.pentaxuser.com/forum/topic/k20d-vertical-banding-8841

I'm not saying it isn't your camera though but it seems unlikely, how are they if you shoot in DNG?

That last shot is just how an unbanded pef file looks at 400% with Pentax Photo Browser. Someone sent me a couple of PEFs and they are consistent. So it's just how that particular software works. That's reassuring - it means that my photos come out either with banding or normal. It's good to know too that I can correct the banding with the appropriate software. Does anyone know how to do this in Lightroom?, which is what I will probably end up getting. But I do want the camera properly repaired.

Thanks for the link to the other thread. I did print it off and send it to Pentax at the time of the first attempted repair so they could see what was done with other cameras with the same issue as mine.

Thanks for the replies and the assistance. I have made progress with my understanding of this issue.