[JimmyL]

I just bought my K5 iis in Oct. Some sunset pictures showed a bright spot in the darkness - as i zoomed in it appeared to be 9 pixels (3x3) were extremely bright. a group of pixels around them were glowing somewhat brighter. I used Pixel Mapping and they disappeared. My question - I see "dead pixels" discussed here - is a 3x3 group of them normal?
Thanks JimmyL

[Adam]

I just bought my K5 iis in Oct. Some sunset pictures showed a bright spot in the darkness - as i zoomed in it appeared to be 9 pixels (3x3) were extremely bright. a group of pixels around them were glowing somewhat brighter. I used Pixel Mapping and they disappeared. My question - I see "dead pixels" discussed here - is a 3x3 group of them normal?
Thanks JimmyL

I've seen multiple adjacent hot pixels before, but it's not likely for 9 pixels to die in the same area. Could you post an example developed from a raw file?

[JimmyL]

I took the pictures in "best quality" 16mp jpg - then I pixel mapped and it fixed the problem - so I don't have a RAW sample. Is the jpg version not a valid way to evaluate the problem? Is it possible that there were not 9 pixels and the jpg interpreted the data that way?

[JimmyL]

Here's a screen shot:

Attached Images

 

[PPPPPP42]

My K20D did that right after I got it used off ebay a long time ago, even in first short exposures so it wasn't an overheat or something. I have heard of large burned spots on other cameras in various forum threads. It was an intermittent huge hot spot that clearly showed up in all the pictures. The pixel mapping darkened the bunch, and now if you pixel peep in just the right area of my pictures you will see what looks like a tiny (actually massive from a pixel count standpoint) faint cigarette burn. Its in every single picture in my album that isn't a scanned film image but good luck finding it in almost all of them even when you know where it is.
It may seem like the end of the world, but its pretty easy to fix in photoshop on the very few pics where it lands in a highly visible spot which is much more rare than you'd think. If its under warranty send it in, it won't get better if your issue is the same as mine though it might be intermittent. Make sure you have a lens cap pic clearly showing the burn spot before you send it in just in case it temporarily goes away. Don't pixel map fix if you are going to send it in.

This is before the pixel map fix (lens cap pic):
https://www.pentaxforums.com/forums/members/46390-pppppp42/albums/4594-pictures/picture68037.jpg

This is after:
https://www.pentaxforums.com/forums/members/46390-pppppp42/albums/4594-pictures/picture68038.jpg

EDIT: mine in after fix pictures in original resolution when pixel peeping shows up as a line of blacked out pixels almost 9 pixels long with a flare around it of blur. Yours is much smaller in the pic you posted so you will likely be just fine with the pixel map fix. Most of the glitch is flare usually and I misunderstood and thought the actual dead spot was 9 pixels not including flare.

[lister6520]

That image represents one hot pixel. It is the de-bayering, noise reduction and jpeg encoding that spread the effect to the adjacent pixels.

[Adam]

That image represents one hot pixel. It is the de-bayering, noise reduction and jpeg encoding that spread the effect to the adjacent pixels.

Exactly!

Adam
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[JimmyL]

As I posted the picture I noticed that it could possibly just be the brightest pixel in the center
with the problem. Thanks for the replies.
JimmyL