Refer to post #3 directly, ignore the following crap...


This post has been edited by AlamakLor: Aug 1 2007, 01:55 PM

oh man... you're scaring me

I found a few on my new camera, I'm contemplating sending it in to get the pixels remapped.

Ignore the first post and use this guide to test the sensor:

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 )
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.

If you want to find out starting from what ISO the crapped pixels manifest, do the same shot and slowly lower the iso. Mine start showing @ iso800.

I was reading A100 review on dpreview....apparently same case with sony....why am i not surprised....sony sensor...

OT a bit. a new cam? d200 ah? wah lao rich fellow

D200? in my wish list lar.....using D40 like you only...had to downgrade from D50. Checked the D50 I sold, that one had perfect sensor....well probably mapped out la

can view the dead pixels through the cam's lcd itself or need the software you posted?

u dont need any software, just take the test picture, then look at it on ur pc. Upload it here so that I can double check for you too

ok... i see those things you're mentioning about... hmmm

wait for my upload

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Added on August 1, 2007, 1:20 pm

counted 4 of em little buggers....

This post has been edited by wlcling: Aug 1 2007, 01:20 PM

yeah I found 4 on yours (circled):

But your sensor seems to have lots of dusts.....might wanna check that too.

This is mine:


Try to use 30sec exposure and see if you can find more. If your cam still has warranty, drop it off nikon service centre and get them remapped.

This post has been edited by AlamakLor: Aug 1 2007, 01:44 PM

4 seems to be the common number!....

u mean those grey specks are dust... i thought that was long exposure noise... lol

yah... still has warranty.... i'll get it cleaned at the same time too.... thks mate...

This post has been edited by wlcling: Aug 1 2007, 01:47 PM

hell yeah they are dusts....lots and lots of them...u see any in my pix? lol
when u drop the cam in, they will clean eveything, just tell them you need "defective pixel remapping & sensor dust cleaning" check it before warranty expires too, they are like monitor pixels, can die or go faulty with more usage.

I found program leaked from nikon where u can diy remapping pixel but its only good for D100

This post has been edited by AlamakLor: Aug 1 2007, 01:59 PM

i almost wonder if you change lenses in a vacuum...

I never change lens in public, and when i change lens...i do it quickly 1

1) prepare lens to be changed
2) remove rear cover
3) unmount lens
4) blow the camera chamber with blower kau kau
5) blow lens rear element kau kau
6) lock!

i havent seen a single speck of dust in my sensor both old D50 and new D40

alamak , yours got 5

Champion mar not a good thing to be proud of

i'll check my d40 also. maybe mine got more le.

Here's mine. I never notice any.

Help double check pls.

saw a few at the bottom region.. but i'm not too sure...

yeah, zoom in edi, can see quite a few.

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Added on August 1, 2007, 8:48 pmHmm, my cam so new also got a lot quite a few hot pixels.

Should I fix it asap?

Would the problem come back again?

Should I even panic or get worried?

Is this problem common amongst DSLR?

I have zoomed in and circled whatever i can find.

Quite shocking!

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Added on August 1, 2007, 9:54 pmActually 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?

This post has been edited by calvin_gsc: Aug 1 2007, 09:54 PM

Calvin, send it it, there's too many of them. Don't count on the noise reduction to "fix" the problem, some of mine can't be fixed even with nr on. I called nikon and they say of there's over 20 dead.hot pixels, they will replace the sensor and remap the new one.

I'm gonna send mine in, and gonna be 3 weeks without camera

Actually, how often is one gonna take a photo with ISO3200 and 10 seconds exposure and with NO NR at all?

alamaks....my warranty over dee

oh well... u can always get a free cleaning with that anyway....

Dont worry lor.

What are the settings u normally use for your photo?

Got ISO3200 often? and 10seconds exposure? no NR?

I usually shoot at 1600 MAX, but even at iso800, some are already visible. No harm getting it fixed.

mine got over 20 dots




hahahahah. just joking

At 800x600, you wont be able to see any hot pixels.

I took my larger sized picture with significant hot pixels and resized it to 800x600, and I can't find any hot pixels also.

see for yourself



Maybe you should upload a picture with higher resolution with at least 3MP.

And I also noticed, your shot above with a D200 has so much less noise!

not that my eyes can really see the hot/dead pixels
but things meant to be fixed are meant to be fixed

my warranty....

eh wait...mine is unfilled warranty

post up a pix, ill check for you, unless u scare there's lots and lots of them Nikon over here dun even bother with seeing the warranty paper...they just want proof of purchase...im gonna send mine camera in next week, play a little more first. They say they will be replacing my sensor.

serious? means the receipt more important than the waranty card???

grey color and green color .. is also a dead pixels? Omg... i have so many leh H!H!HH! HELP ! i already circled it out .. just need help to double check. Thank you

May I know how old is your camera?

yup, there's no need for the warranty card. Just a photocopy of the receipt, description of the problem, and send the cam in. Don't even in RA#. I called to check again today and this time they told me a week. I told them i found 20+ dots, each of them consist of 4-6 pixels together...that's over a hundred of them. The girl on the phone said "oh my god" Ah well, seems like D80's sensor is even more kay

bbtat, yes, really lots of them, more than twice the amount of what i have....almost the same level like those D100 liao....get it fixed. Tell nikon you take lots of long exposure shot, over a min, and you see lots of these pixels. You want them to map out everything see up to 2 sec, @ high iso.

Dead pixel can be fixed? And what's remap?

Actually there's no sensor that has 0 dead pixel. Camera manufacturer usually mapped the problem pixel out before sending it out, olympus camera has automatic maintenanance system that will map out dead pixels during certain time. Basically the camera will check for the dead pixels, then take the data around the surrounding pixels, interpolate the data, and clone the closest pixel to the dead pixel. This is done at the firmware level, the firmware level.

Another solution is to replace the sensor, but even replaced, there will still be dead pixels, and they will map it out. IIRC nikon can only map out 200+ pixels, if there's more than that, they will replace the sensor, then remap the new one.

wow, i didnt know about this....
but if my lcd got dead pixels also, then very hard to see?

If you know particular part of your lcd got dead pixel, look for other part of the screen lor.

enlarge the picture n move around with mouse lo...

Erm
2 months old. .. omg.. what happen.. u help me to checkeeD?

Well, I wouldn't want to scare you or anything.

Maybe can bring to Nikon for checkup and tell them about it.

Get it fixed asap lor.

green and white.. and the red and blue .. all is dead pixels? or it is just a dust? Ermmm .. i m so scare !

they're not dead pixels, apparently hot pixels. can be fixed. Dust is not colored.

Erm.. if i send back to warranty .. how should i said? and will they try to avoid for my claim? ty

I envy DSLR users. The blank pictures are so clean compared to mine.

Gosh, my S3 IS has terrible amount of hot pixels. Should non-DSLR users be concerned about this?

This post has been edited by mengsuan: Aug 3 2007, 11:20 PM

how do they actually remap those pixel on the sensor?

disable that pixel and share its value with neighbour pixel?

Exactly. They interpolate the surround pixels, not just the one that is next to it though.

@bbtat
check previous page, I've mentioned the exact phrase you need to tell them to get this fixed.

Urrgh.. I feel that I'm in trouble. There is over hundreds(or probably thousands) of hot pixels, even at ISO200. I hope this is normal for non-DSLR cameras.

Addon: And I don't think those are noise. It's a distinctive white/blue/red pixel.

This post has been edited by mengsuan: Aug 3 2007, 11:26 PM

over thousand? you serious?
I just checked my old SD400, there's less hot pixels than my nikon:

Okay, maybe a thousand is a little exaggerated. But I still doubt the reliability of my camera. There are quite plenty on the bottom left; Blue, red and lots of white pixels.

The picture:




Zoom to 100% and you'll see more hot pixels.

wah lau....i didnt need to resize already can see dots as kau as ur avatar

Then how ah? I'm going to write to Canon already!

This is mine, S3IS, 10sec, iso80

ISO80 wor, of course nothing lar.

Ohh... I shall post up shot with the highest ISO?

Here is it, looks very noisy:



ISO800

This post has been edited by kelvinyam: Aug 5 2007, 10:42 AM

yes, claim warranty....no need "give face" to canon 1. maybe if u complain enough they will replace it with a 350D

wah.. my 350d, counted got 19 dead pixels.. mostly blue,red and white. got one purple one also @.@

AlamakLor, what ISO shall I use to create this test shot? I tried it with ISO800 and it's terrible.

lol there is a similar thread here.. i see a lot of people confuse between hot pixel and dead pixel..

Q: What does a 'dead pixel' mean ?

A: Dead pixels are elements on the CCD that do not work at all. This is determined by checking the RGB and luminance value of the pixel. In case of a lens cap shot this should be close to black. If the pixel is instead white or almost white it is a dead pixel.

Q: What does a bad or hot pixel mean ?

A: A bad or hot pixel is determined by checking the luminance of the pixel. If the luminance falls above the threshold it is added to the bad pixel list. Depending on the length of exposure and other circumstances bad pixels may not be that bad but noise that can be considered to be ok.


In normal human terms..it means :-

dead pixel can be seen at any exposure taken with any setting.

hot pixel can be seen at long exposure only.


This is how i do my test..

1. warm up the sensor..(take few shots)
2. set iso 100
3. turn off Noise reduction
4, turn off Noise filter
5. set exposure to 20seconds
6. F8
7. close the viewfinder and lens cover
8. take picture in highest resolution..for mine is 10megapixel
9. view the pic on screen and use the deadpixeltest.exe to view the dead pixel or hot pixel

As for my case..damn sad case..1200 hot pixel taken at 20 s exposure iso 100, f8 at 10megapixel

This post has been edited by hellfire8888: Aug 27 2007, 04:11 PM

olympus? IIRC, u can map it out with olympus slr, check the manual...i believe the feature is still there with newer slrs.

LOL!!
this is funny

btw, how to test compact camera for hot pixel?
same method?

pixel mapping can map out dead pixel not hot pixel...both of them are not the same..

i m done the test on my panasonic fz20 with iso400 8sec F8 and the DeadPixelTest.exe reported :

0 hot/dead pix at hot pix threshold:60, dead pix threshold:250

but
51640 hot pix / 7274 dead pix at hot pix threshold:6, dead pix threshold:6

I just wonder, what does the threshold mean?

sticking back to hot pix threshold:60, dead pix threshold:250 should be just fine?

phwoar...

10 sec shutter @ ISO 3200 1 hot pixel only
30 sec got around 28 hot pixels :S can see quite a bit of dust summore

2 week old D40x only nia... last week I went to the service centre @ PKNS to get my pop up flash tightened and the stupid lady took my lens off and took the body to the back without putting a cap on. Tomorrow gonna go back there and fuk them up kau kau.