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berujung
01-12-2005, 03:05 PM
I just purchased Canon 20D about one month ago. Yesterday, I noticed there's already a dot on the LCD screen. Is that a common problem with Canon or any digital camera?

jeisner
01-12-2005, 05:46 PM
I have one dead pixel on the screen of my *ist DS since new, I am not going to endure the stress of trying to return it under warranty unless it gets worse, one dead pixel isn't that noticable, and it doesn;t affect the pics, so I can live with it!

judge9847
01-12-2005, 06:22 PM
I just purchased Canon 20D about one month ago. Yesterday, I noticed there's already a dot on the LCD screen. Is that a common problem with Canon or any digital camera?
That's a bit odd because one dead pixel on the LCD is unlikely, in normal circumstances, be noticed ... are you sure it's what you say it is?

D70FAN
01-12-2005, 07:19 PM
I just purchased Canon 20D about one month ago. Yesterday, I noticed there's already a dot on the LCD screen. Is that a common problem with Canon or any digital camera?

You must have really good eyes. Picking out one pixel in 118,000 is pretty good. Guess I should check my D70...

jeisner
01-12-2005, 09:56 PM
To see mine on a normal photo is impossible but take a photo with the lens cap on so the image is pure BLACK, you can now clearly see the dead pixel. For this reason I first noticed it when navigating the menus....

judge9847
01-13-2005, 04:03 AM
To see mine on a normal photo is impossible but take a photo with the lens cap on so the image is pure BLACK, you can now clearly see the dead pixel. For this reason I first noticed it when navigating the menus....
... that it's an urban myth ... it doesn't prove a thing.

To quote Nikon - who I assume know a thing or two about cameras - it's a "common mistake in testing for Dead or Stuck pixels is to cover the lens with the lens cap and set the camera to AUTO. Setting to Auto will cause the camera to lower the shutter speed thus resulting in taking a long exposure. This produces some red, greenish and sometimes white pixels. This is a normal state and it is referred to as Christmas Tree artifacting. In addition, a dead pixel is dead all the time and would not show up with this test since the pixel is black."

Here's what they suggest you do:

STEP 1 : Take some shots of of normal indoor environment such as a portrait.

STEP 2 : Compare two shots using a photo editor such as Photoshop where it allows you to compare two images side by side. If you notice there is a bright pixel occurring on one image, do the comparison on the other image; both should have the bright pixel on the same location. If it is on the same location it can be considered as a HOT pixel."

If that's the case, and it really brasses you off - take the camera back but for ONE pixel on the LCD that you can see I personally wouldn't bother. What I might bother about is the ones you can't see ... and it's almost a certainty there are others that aren't causing you grief, especially if there's nothing on the images you take. It's something that affects almost every LCD there is.

Now you know ;)

jeisner
01-13-2005, 06:34 PM
whatever they reckon. ;)

But if I do what I said (and on slow shutter) I get just one white pixel, on the LCD but NOT on the photo once on the computer. Also if I browse the menu (I said that before) which is mainly black I can always see one odd whitish pixel....

Make what you will of it.

I did already say I couldn't be bothered returning over such a minor issue ;)

Alnath
01-13-2005, 06:44 PM
That's a bit odd because one dead pixel on the LCD is unlikely, in normal circumstances, be noticed ... are you sure it's what you say it is?

My mates Ixus IIs has one stuck blue and very iritating pixel on the TFT.

ktixx
01-18-2005, 11:15 PM
Dead pixels don't always show up as black, I have seen red dead pixels, and this is on 32" lcd screens where there are ALOT more than 100,000 pixels. I know someone who got rid of their $5,000 32" sony LCD screen because it had 1 dead pixel so it is noticable. LCD (Liquid Crysal Diods) have 3 boxes inside each pixel, one housing red liquid, one blue and one green. By applying voltage to the pixels, they can turn "on" of "off" to form a variety of colors, or they can even be darkened to prevent the backlight from showing through, creating the appearence of black. Basically what I am saying, is there are tons of variations of dead pixels, they can be red, green, blue or even black. From my experiences I have seen pixels not working from day 1, so yes this can be normal, but as said in a previous post, it will not affect the picture quality, so the only reason to return the camera is if you want to.
Ken

D70FAN
01-19-2005, 06:31 AM
Dead pixels don't always show up as black, I have seen red dead pixels, and this is on 32" lcd screens where there are ALOT more than 100,000 pixels. I know someone who got rid of their $5,000 32" sony LCD screen because it had 1 dead pixel so it is noticable. LCD (Liquid Crysal Diods) have 3 boxes inside each pixel, one housing red liquid, one blue and one green. By applying voltage to the pixels, they can turn "on" of "off" to form a variety of colors, or they can even be darkened to prevent the backlight from showing through, creating the appearence of black. Basically what I am saying, is there are tons of variations of dead pixels, they can be red, green, blue or even black. From my experiences I have seen pixels not working from day 1, so yes this can be normal, but as said in a previous post, it will not affect the picture quality, so the only reason to return the camera is if you want to.
Ken

Just for clarity: LCD=Liquid Crystal Display.

ktixx
01-19-2005, 10:07 PM
Yea my mistake, I have read a few reviews and some of them say "diode" but the dictionary defines it as "Display", my mistake.

Rex914
01-25-2005, 10:48 PM
Yea my mistake, I have read a few reviews and some of them say "diode" but the dictionary defines it as "Display", my mistake.

You are probably confusing it with the similar term LED (light emitting diode).

Dead pixels are very common an any devices using LCD's. One product in particular comes to mind - laptops. Laptops are notorious for having dead pixels. When you have those big 17" laptops with 1920 x 1200 WUXGA (2 megapixel) display, there's a good chance that 1 of those will be a dud, and worse yet, most companies don't let you return it unless there are multiple dead pixels.