Camera sensor for HOT/DEAD pixels

[calvin_gsc]

I have learnt how to look for hot/dead pixels from this thread in lowyat.

1) Set iso to highest sensitivity possible (H1.0 on D200)
2) Set to shutter priority, set shutter to 10s (more than enough..unless u really wanna do 30sec sweat.gif)
3) Set camera to manual focus, leave the lens cap on
4) Turn off ALL noise reduction, both high iso & long exposure NR
5) Set QUAL to Fine jpeg
6) Cover the viewfinder with ur hand and FIRE AWAY!

look at the black picture, if u have stuck/dead/hot pixels, u'd see them easily, they appear as a normal R/G/B/white dot...sometimes in a + sign.

http://forum.lowyat.net/index.php?act=ST&f=62&t=497343&st=0#entry12689668

I have found quite a no on my 4 month old D80.

Should I be worried about it?

The thread starter suggested to send to nikon to do defective pixel remapping.

This is my result
http://img523.imageshack.us/img523/5097/dsc1105copypu9.th.jpg (http://img523.imageshack.us/my.php?image=dsc1105copypu9.jpg)

Taken with 10second exposure, no ISO NR, no Long exposure NR.

[siew]

You should take it back to nikon. No sensors are perfect. Dead pixels are mapped before they leave nikon.

[calvin_gsc]

You should take it back to nikon. No sensors are perfect. Dead pixels are mapped before they leave nikon.

Nikon Malaysia would be able to remap the sensor pixels?

Would it take long?

I have to leave for US to pursue my studies, so donno got time or not.

[ND40]

maybe you can try this
CCD Dead Pixel Test (http://www.starzen.com/imaging/deadpixeltest.htm)

[calvin_gsc]

maybe you can try this
CCD Dead Pixel Test (http://www.starzen.com/imaging/deadpixeltest.htm)

Yeah yeah, can use to test, but can't use to FIX the pixels.

[ND40]

okay.... my bad... don't read ur msg carefully....

Pxiel remapping? never heard about that. I thought if dead pixel then have to change the whole CCD?

[calvin_gsc]

Actually hor, I have done a few more tests.

With ISO NR and Long Exposure NR, no hot/dead pixels can be seen at ISO400 and ISO3200.

Even Without ISO NR and Long Exposure NR, no hot/dead pixels can be seen at ISO400 photo.

So, actually if we print out photo, nothing to worry also right?

[siew]

Try taking a few frames to see if the coloured pixels are at the same exact location. Could be noise! BTW what is the ISO? I noticed that your exposure is very long 10 seconds. At that exposure you'll get digital noise. I just googled some info on the net http://www.isi.edu/~johnh/PAPERS/Heidemann01b.pdf Hope it helps. I guess your cam is working fine :D.

[calvin_gsc]

Try taking a few frames to see if the coloured pixels are at the same exact location. Could be noise! BTW what is the ISO? I noticed that your exposure is very long 10 seconds. At that exposure you'll get digital noise. I just googled some info on the net http://www.isi.edu/~johnh/PAPERS/Heidemann01b.pdf Hope it helps. I guess your cam is working fine :D.

Yeah, purposely set at ISO3200 and 10s exposure.

No ISO NR and Long exposure NR.

To see truly whether your sensor got hot pixels or not.

[mobbes]

maybe you can try this
CCD Dead Pixel Test (http://www.starzen.com/imaging/deadpixeltest.htm)
Shoot with cap on for various speeds & smallest aperture ... shoot RAW. Open in raw converter & set everything to flat / 0. Then open file & save into tiff format ... enormous file! Test the tiff file. good luck

[ykgen]

actually they wont affect the pix quality.. as our meat eyes wont notice them.. unless u shoot only pitch black..

[calvin_gsc]

Actually how often do we take a photo with ISO3200 and at 10s exposure with NO NR?? :?

[ShaolinTiger]

Hot pixels and dead pixels are different things, try not to confuse the two :D

You can take the camera back to nikon to map them out (the value for the dead pixels will be averaged from the surrounding 4 pixels).

But seriously in real life situations, you won't notice it.

Dust is something to worry about, generally dead/hot pixels are not.

A few out of 10 million pixels too, doesn't make much diff.

[calvin_gsc]

Hot pixels and dead pixels are different things, try not to confuse the two :D

You can take the camera back to nikon to map them out (the value for the dead pixels will be averaged from the surrounding 4 pixels).

But seriously in real life situations, you won't notice it.

Dust is something to worry about, generally dead/hot pixels are not.

A few out of 10 million pixels too, doesn't make much diff.

Is this bad?

Shot at ISO3200, 10s exposure, no ISO NR, no long exposure NR.
http://img523.imageshack.us/img523/5097/dsc1105copypu9.th.jpg (http://img523.imageshack.us/my.php?image=dsc1105copypu9.jpg)

@ISO3200 but with both NR on
http://img503.imageshack.us/img503/6112/dsc1136nriso32001600x12hb7.th.jpg (http://img503.imageshack.us/my.php?image=dsc1136nriso32001600x12hb7.jpg)

ISO400 with NO NR at all.
http://img339.imageshack.us/img339/4451/dsc1138iso4001600x1200ex6.th.jpg (http://img339.imageshack.us/my.php?image=dsc1138iso4001600x1200ex6.jpg)

[Kenshin-X]

I sent my D80 to Nikon a few months back for hot pixels I accidentally found. They were nice enough to change the entire CCD for me :D satisfied Nikonian!

[calvin_gsc]

I sent my D80 to Nikon a few months back for hot pixels I accidentally found. They were nice enough to change the entire CCD for me :D satisfied Nikonian!

Your hot pixels were seen at what settings on your camera?

Cause, my hot pixels only appear at high iso and long exposure.

ISO3200 +10s exposure.

Try using the above and see whether it still exhibits hot pixel problem.

Cover the lens with cap, set lens to manual focus. Turn off all NR (ISO and long exposure).

Take the shot.

[Kenshin-X]

Your hot pixels were seen at what settings on your camera?

Cause, my hot pixels only appear at high iso and long exposure.

ISO3200 +10s exposure.

Try using the above and see whether it still exhibits hot pixel problem.

Cover the lens with cap, set lens to manual focus. Turn off all NR (ISO and long exposure).

Take the shot.


I shot at 1.6 seconds, ISO 3200
Nope, no hot/dead pixels observed. Few months back I shot a pic in my room,if im not mistaken at ISO 1600 1/5 s and I saw a red dot on the left bottom quarter of the LCD screen. After taking a few photos, the red dot is at the same place everytime. Soon after, I brought it back to Nikon. They changed the entire CCD for me till now no problem.:D