K-7 / Missing Pixels / Dropouts

PropFan · 01-02-2010, 06:04 AM

Hope I'm posting in the correct forum. I'm a new K-7 user, and the attached photo excerpt is one of my first attempts. I am wondering about the cause of the missing pixels or dropouts in the areas I have circled. Any thoughts/explanations? This occurred on at least two other photos. I used the Green setting with a new Kingston 16GB SDHC Class 6 card. I had just brought the camera outdoors, so I don't think low temp is an issue.

Attached Images

ytterbium · 01-02-2010, 06:14 AM

You say it occurred in at least two other photos. So its not in all pictures - or it is, just less visible. In the same exact places?
Looks more like a SD problem. Have you tried any other SD card, preferably non SDHC.
Can you post the full exif of all those shots with this problem and some (images and exif) without this issue.

bymy141 · 01-02-2010, 07:24 AM

This does not look like hot or black pixels.
You can only see such pixels when zoomed in on a picture and your camera has a facility to map them out (see manual).
Such stripes I've never seen or heard of.

You can try the dead / stuck pixel mapping, but the SD card suggestion may be another thing to explore.

PropFan · 01-02-2010, 08:27 AM

Just took some more photos with this card, and I'm seeing the same thing on those pictures. The missing pixels are in different locations in each picture. I'm starting to suspect a bad (or counterfeit) SD card. I bought two of these on eBay from a seller who had a lot of positive feedback. I'll try the other card and see what happens. The write time on these cards seems to be slower than the 4GB Class 4 SanDisk card that came with the camera.

ytterbium · 01-02-2010, 09:05 AM

Even if it occurs only with those new cards, keep in mind that card issue is not necessary card related. Because of this, you should take a look at all involved variables (image content, camera settings, other configuration - lens, flash, batteries).

I remember reading that once bad card writes were caused by something other than card defect (i believe it was incorrectly formatted card or something like that). If you have the chance you could also try the card in different configurations (USB image transfer, card reader, using different camera - for both transfer and capture).

dragonfly · 01-02-2010, 09:47 AM

Did you initially format the card with your camera?

PropFan · 01-03-2010, 08:25 AM

Dragonfly: I thought maybe you had hit on something because I actually didn't format this card in the camera initially. I just popped it in and started shooting. But, after formatting it in the camera, the problem persists. I have, however, isolated the problem to just this one card. So, I'm virtually certain I have a bad card.

DonP · 01-03-2010, 09:05 AM

Originally posted by PropFan

Just took some more photos with this card, and I'm seeing the same thing on those pictures. The missing pixels are in different locations in each picture. I'm starting to suspect a bad (or counterfeit) SD card. I bought two of these on eBay from a seller who had a lot of positive feedback. I'll try the other card and see what happens. The write time on these cards seems to be slower than the 4GB Class 4 SanDisk card that came with the camera.

Ebay is rampant with counterfeit flash memory cards as are flea markets. No manufacturer is immune from the problem of having their cards counterfeited by cheap, unreliable manufacturers. ALWAYS buy from a reputable source. Memory is cheap but your images can't be replaced.

PropFan · 01-04-2010, 05:44 AM

Don: lesson learned. As I indicated, the seller had a lot of positive feedback, and the packaging (if these are fakes) is very convincing. But, I now notice there is no serial number on the card, unlike the authentic SanDisk card that came with the camera. I'm going to try to call Kingston to see if they can confirm whether these are the real deal or not.

PropFan · 01-04-2010, 11:17 AM

Update: Kingston confirmed the cards are not authentic. I emailed the eBay seller and received a full refund in my PayPal account within one hour. Maybe I should go buy a lottery ticket today.

01-02-2010, 06:04 AM	#1
PropFan New Member Join Date: Dec 2009 Location: Kansas Posts: 22	K-7 / Missing Pixels / Dropouts Hope I'm posting in the correct forum. I'm a new K-7 user, and the attached photo excerpt is one of my first attempts. I am wondering about the cause of the missing pixels or dropouts in the areas I have circled. Any thoughts/explanations? This occurred on at least two other photos. I used the Green setting with a new Kingston 16GB SDHC Class 6 card. I had just brought the camera outdoors, so I don't think low temp is an issue. Attached Images

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01-02-2010, 06:14 AM	#2
ytterbium Veteran Member Join Date: Jan 2008 Posts: 1,076	You say it occurred in at least two other photos. So its not in all pictures - or it is, just less visible. In the same exact places? Looks more like a SD problem. Have you tried any other SD card, preferably non SDHC. Can you post the full exif of all those shots with this problem and some (images and exif) without this issue.

01-02-2010, 07:24 AM	#3
bymy141 Veteran Member Join Date: Aug 2007 Photos: Gallery Posts: 1,563	This does not look like hot or black pixels. You can only see such pixels when zoomed in on a picture and your camera has a facility to map them out (see manual). Such stripes I've never seen or heard of. You can try the dead / stuck pixel mapping, but the SD card suggestion may be another thing to explore.

01-02-2010, 08:27 AM	#4
PropFan New Member Join Date: Dec 2009 Location: Kansas Posts: 22 Original Poster	Just took some more photos with this card, and I'm seeing the same thing on those pictures. The missing pixels are in different locations in each picture. I'm starting to suspect a bad (or counterfeit) SD card. I bought two of these on eBay from a seller who had a lot of positive feedback. I'll try the other card and see what happens. The write time on these cards seems to be slower than the 4GB Class 4 SanDisk card that came with the camera.

01-02-2010, 09:05 AM	#5
ytterbium Veteran Member Join Date: Jan 2008 Posts: 1,076	Even if it occurs only with those new cards, keep in mind that card issue is not necessary card related. Because of this, you should take a look at all involved variables (image content, camera settings, other configuration - lens, flash, batteries). I remember reading that once bad card writes were caused by something other than card defect (i believe it was incorrectly formatted card or something like that). If you have the chance you could also try the card in different configurations (USB image transfer, card reader, using different camera - for both transfer and capture).

01-02-2010, 09:47 AM	#6
dragonfly Veteran Member Join Date: Jun 2009 Location: on the wall Photos: Gallery Posts: 715	Did you initially format the card with your camera?

01-03-2010, 08:25 AM	#7
PropFan New Member Join Date: Dec 2009 Location: Kansas Posts: 22 Original Poster	Dragonfly: I thought maybe you had hit on something because I actually didn't format this card in the camera initially. I just popped it in and started shooting. But, after formatting it in the camera, the problem persists. I have, however, isolated the problem to just this one card. So, I'm virtually certain I have a bad card.

01-03-2010, 09:05 AM	#8
DonP Inactive Account Join Date: Nov 2009 Location: Indiana Posts: 101	Originally posted by PropFan Just took some more photos with this card, and I'm seeing the same thing on those pictures. The missing pixels are in different locations in each picture. I'm starting to suspect a bad (or counterfeit) SD card. I bought two of these on eBay from a seller who had a lot of positive feedback. I'll try the other card and see what happens. The write time on these cards seems to be slower than the 4GB Class 4 SanDisk card that came with the camera. Ebay is rampant with counterfeit flash memory cards as are flea markets. No manufacturer is immune from the problem of having their cards counterfeited by cheap, unreliable manufacturers. ALWAYS buy from a reputable source. Memory is cheap but your images can't be replaced.

01-04-2010, 05:44 AM	#9
PropFan New Member Join Date: Dec 2009 Location: Kansas Posts: 22 Original Poster	Don: lesson learned. As I indicated, the seller had a lot of positive feedback, and the packaging (if these are fakes) is very convincing. But, I now notice there is no serial number on the card, unlike the authentic SanDisk card that came with the camera. I'm going to try to call Kingston to see if they can confirm whether these are the real deal or not.

01-04-2010, 11:17 AM	#10
PropFan New Member Join Date: Dec 2009 Location: Kansas Posts: 22 Original Poster	Update: Kingston confirmed the cards are not authentic. I emailed the eBay seller and received a full refund in my PayPal account within one hour. Maybe I should go buy a lottery ticket today.