How to test for dead pixels

Can some one tell me the best way to test for dead pixels.

Thanks

I was going to do a search on the subject but the search engine is down again. So here goes: For LCD or EVF bad pixels can either be always on or always off.

As I understand it, in CCD or CMOS, bad pixels wouldn't capture data and the pixel will show us as a dark spot.

To test LCD or EVF just point your camera at a white sheet of paper and inspect closely if there are any black spot that doesn't move as you move the camera. Then cover the lense to see if there are any light spot that is always on.

To test CCD or CMOS, take a few photos of the sky or out of focus white paper and on you computer monitor, see if there are any dark spots that remains at the same spot. I am not sure if the test where you cover the lens and take a longer exposure of .5 or 1 second is for always on pixels on the CCD or CMOS or if it is a test with 5 to 10 seconds to check for noise.

May have to wait for the search engine to be back up to see what has been posted by people who really know what they are talking about!

Chas said:

Can some one tell me the best way to test for dead pixels.

Thanks

Click to expand...

--Tony

Hi Chas,

try this link:

http://home-4.worldonline.nl/~t800373/

On this site you will find a small program and information how to test.--Leif http://www.pbase.com/ltobias/

Hi Chas,

try this link:

http://home-4.worldonline.nl/~t800373/

On this site you will find a small program and information how to test.--Leif http://www.pbase.com/ltobias/

Here is a program to test files for dead pixels: http://www.starzen.com/imaging/deadpixeltest.htm

Tony said:

Chas said:

Can some one tell me the best way to test for dead pixels.

Thanks

Click to expand...

--
Tony

Click to expand...

Duane Steiner said:

Here is a program to test files for dead pixels:
http://www.starzen.com/imaging/deadpixeltest.htm

Click to expand...

I'd be surprised if an expensive camera like the D7 didn't map out any bad pixels. It wouldn't take much firmware to record the locations of the few bad pixels, and set them to the average of the nearby pixels of the same color. In which case the program wouldn't find anything.