Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-25-2014, 02:11 AM   #1
Site Supporter
The Madshutter's Avatar

Join Date: Mar 2014
Location: San Ginesio
Posts: 256
645D dead pixel after 275 exposures - solved!

Well, it had to happen I guess - I went to Cappadocia for a 4-day shooting, and after coming back home and starting to work on the photographs I found a very nice looking, very bright red line in any image taken after exposure _6450275: since my first image of the trip is _6450263, basically all the 300 images I shot over there got it. Once I got home and I found out, I immediately run a pixel mapping which thankfully solved the problem the first time over. This things happen of course, and I am glad Pentax included a pixel-mapping feature in the 645D which immediately fixed the issue for me. I wasn't expecting it to happen so soon though, which is why I wasn't checking pictures at 100% in the field - sadly so, if I did check now I'd have many less ruined pictures. Oh well, lesson learned: now, all I have to do is fix the red line in the ~60 keepers from the trip...

So I guess the point of this story is, no matter how new your camera is, keep checking for dead pixels - they can creep in when you less expect them!

04-25-2014, 03:18 AM   #2
Site Supporter




Join Date: Apr 2011
Photos: Albums
Posts: 3,511
Sounds like you should be taking this up with the supplier. Warranty type situation. There must be a fault with a sensor to have failure so early.

The pattern with electronic stuff is that they have a high very early failure rate, followed by an extended high reliability interval and then failures increase as they start to get old. The 'bathtub' curve. Warranty is to protect the buyer from the burn in period failures.
04-25-2014, 04:55 AM   #3
Site Supporter
The Madshutter's Avatar

Join Date: Mar 2014
Location: San Ginesio
Posts: 256
Original Poster
Tim, you are of course right about the failure pattern with electronics - however, in this case, since:

- the issue was just one dead pixel that I could fix with the pixel mapping thing (camera now works perfectly again);
- having Pentax taking care of it will mean for me to be without camera for a while (months perhaps if they'll have to ship it to Japan);
- the camera has 8 more months warranty on it;

I think I'll keep using the camera and see what happens, and eventually send it in later on if more dead pixels will pop up. If not, and if the incident will be confined to the one dead pixel, the better, since otherwise the machine is perfectly fine.
04-25-2014, 01:21 PM   #4
Pentaxian
johnyates's Avatar

Join Date: Aug 2011
Location: Saskatoon, SK
Posts: 1,192
Just had a look at your web site--your pictures are AWESOME!

04-25-2014, 01:36 PM   #5
Site Supporter




Join Date: Apr 2011
Photos: Albums
Posts: 3,511
QuoteOriginally posted by The Madshutter Quote
Tim, you are of course right about the failure pattern with electronics - however, in this case, since:

- the issue was just one dead pixel that I could fix with the pixel mapping thing (camera now works perfectly again);
- having Pentax taking care of it will mean for me to be without camera for a while (months perhaps if they'll have to ship it to Japan);
- the camera has 8 more months warranty on it;

I think I'll keep using the camera and see what happens, and eventually send it in later on if more dead pixels will pop up. If not, and if the incident will be confined to the one dead pixel, the better, since otherwise the machine is perfectly fine.
Thanks. All said in goodwill.

I had interpreted that you had whole rows/columns that showed trouble, which was rather more disturbing to me.
04-25-2014, 02:14 PM   #6
Site Supporter
The Madshutter's Avatar

Join Date: Mar 2014
Location: San Ginesio
Posts: 256
Original Poster
QuoteOriginally posted by johnyates Quote
Just had a look at your web site--your pictures are AWESOME!
Thank you John, I really appreciate it, am glad you enjoyed the site!

---------- Post added 04-26-14 at 12:16 AM ----------

QuoteOriginally posted by tim60 Quote
Thanks. All said in goodwill.

I had interpreted that you had whole rows/columns that showed trouble, which was rather more disturbing to me.
Hello Tim,

you are absolutely right, had I had whole rows or columns off I'd have sent the camera back as fast as I could Thankfully, I could manage with the (very useful) Pixel Mapping feature. Thanks again!
04-26-2014, 04:34 AM   #7
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,400
Just as a note, there are many third party processors that deal with dead pixels also
04-26-2014, 06:03 AM   #8
Site Supporter
The Madshutter's Avatar

Join Date: Mar 2014
Location: San Ginesio
Posts: 256
Original Poster
QuoteOriginally posted by Lowell Goudge Quote
Just as a note, there are many third party processors that deal with dead pixels also
This is interesting, do you mind expanding on the topic a bit? Thanks!

04-26-2014, 11:00 AM   #9
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,400
QuoteOriginally posted by Lowell Goudge Quote
Just as a note, there are many third party processors that deal with dead pixels also
QuoteOriginally posted by The Madshutter Quote
This is interesting, do you mind expanding on the topic a bit? Thanks!
There are plug-ins for dead pixel correction, that are compatible with any adobe (photoshop) compatible program. I forget the one I use linked in with Corey's PSP X but if you do a search on dead/hot pixel correction it is there. I looked for this when my *istD started showing some hot pixels, because there is no pixel mapping to correct this in camera on early DSLRs

Not that I am promoting I but it is just the first entry when I googled hot pixel correction adobe plug in

http://oneslidephotography.com/download-photography-software-hotpixel-adobe-photoshop-plug-in/
04-28-2014, 06:54 AM   #10
Inactive Account




Join Date: Jan 2013
Posts: 17
My understanding is that every digital camera has numerous dead pixels. They are mapped out as part of the manufacturing/assembly process, so you never know about them. As time goes on, more will die, requiring eventual remapping or some form of post-processing correction.

I don't know how many dead pixels the manufacturers allow to be mapped out in production before the sensor is considered a "dud", but I expect the number is surprisingly high.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
645d, 645d dead pixel, camera, home, image, line, medium format, pictures, pixel
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Multiple exposures with 645D FrankC Pentax Medium Format 3 10-13-2013 08:05 AM
K5II preview monitor has dead Pixel & moisture in viewfinder and LCD screen Amante Troubleshooting and Beginner Help 16 09-04-2013 09:09 AM
What's more annoying than a hot/dead pixel? larryinlc General Talk 10 06-06-2013 06:02 AM
dead pixel on kx mustangjoey Pentax DSLR Discussion 7 01-13-2011 11:36 AM
Dead Pixel on *istD Zarkon Pentax DSLR Discussion 2 05-24-2009 08:50 PM



All times are GMT -7. The time now is 10:40 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top