XL1s White Pixel? at DVinfo.net

ronluc8667 · January 19th, 2002, 10:53 PM

With the lens cap on my XL1s camera, and the shutter speed slowed down, I can produce a brite white dot on an external monitor. It's not very obvious under normal lighting conditions, but I was testing this camera out in low light when I first discovered it.

I have a second XL1s (purchased both brand new at the same time), and it does not experience this problem. I'm using the same cable between to the monitor when testing both cameras. Also, I've switched the lenses between both chasis and the problem follows the chasis.

I've done some research on the internet about 'white pixels' and have heard other people with the problem on the XL1. Is there a way to correct this other than taking it back for a new one? This camera is only 1 week 5 days old.

Thanks,
Ron

Chris Hurd · January 19th, 2002, 11:54 PM

Check to make sure it is not actually a tiny bit of schmutz on the back element of the lens or the glass covering the CCD prism on the camera body lens mount. I had this problem once, it would only show up when the electronic gain was cranked up. Sent it in to Canon and it turned out to be a little speck of dust.

If it actually is a hot pixel, it'll have to go back to Canon in order to get masked out electronically. Only they can do that.

Ozzie Alfonso · January 20th, 2002, 01:03 AM

Sounds similar to my problem except that my white pixel is seen, in varying degrees of prominence, under any light condition except when over a white part of the picture.

In my case I suspect, in fact I'm almost sure, that it's a bad pixel. I've had this problem before with other cameras and the problem are bad pixels. When chips are made there is a certain maximum number of bad pixels allowed before QT rejects the chip. More often than not the bad or missing pixels fall outside the field of view. Once in a while they fall right smack in the middle of the picture such as in my case and my camera is only a day old.

Of course, Chris could be right and it's just some schmutz. Hey, schumutz happens.

Nathan Gifford · January 20th, 2002, 08:45 AM

Check real, real good too. I found specks on the lens and CCD prism.

Nathan Gifford

Ozzie Alfonso · January 20th, 2002, 10:29 PM

Would a speck of dust in the lens or the prism show up as black or white? I don't understand why a white speck would be dust. I'm just asking. I stand to be corrected if there's something I don't know about this matter.

Chris Hurd · January 21st, 2002, 12:39 AM

When the shutter or gain is cranked, a dust speck appears white. Don't know why.

What you described sounds like a bad pixel, what Ron described sounds like lens schmutz on the back element. Just gut feelings, not a competent diagnosis, not by a long shot.

January 21st, 2002, 02:04 AM

Chris is as usualy absolutely right.
I Had exactly the same problem with my cam right out of the box.
If I remeber rightly it was a blue speck, which is even more perplexing, but I tool the lens off, and there it was. A tiny bit of dust.... Easy to fix really.
I thought it kind of rude that a brand new assemble would be soiled though.

Paul

January 19th, 2002, 10:53 PM	#1
ronluc8667 Regular Crew Join Date: Jan 2002 Location: Colorado Posts: 31	XL1s White Pixel? With the lens cap on my XL1s camera, and the shutter speed slowed down, I can produce a brite white dot on an external monitor. It's not very obvious under normal lighting conditions, but I was testing this camera out in low light when I first discovered it. I have a second XL1s (purchased both brand new at the same time), and it does not experience this problem. I'm using the same cable between to the monitor when testing both cameras. Also, I've switched the lenses between both chasis and the problem follows the chasis. I've done some research on the internet about 'white pixels' and have heard other people with the problem on the XL1. Is there a way to correct this other than taking it back for a new one? This camera is only 1 week 5 days old. Thanks, Ron

January 19th, 2002, 11:54 PM	#2
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	Check to make sure it is not actually a tiny bit of schmutz on the back element of the lens or the glass covering the CCD prism on the camera body lens mount. I had this problem once, it would only show up when the electronic gain was cranked up. Sent it in to Canon and it turned out to be a little speck of dust. If it actually is a hot pixel, it'll have to go back to Canon in order to get masked out electronically. Only they can do that. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

January 20th, 2002, 01:03 AM	#3
Ozzie Alfonso Major Player Join Date: Nov 2001 Location: New York, NY Posts: 355	Sounds similar to my problem except that my white pixel is seen, in varying degrees of prominence, under any light condition except when over a white part of the picture. In my case I suspect, in fact I'm almost sure, that it's a bad pixel. I've had this problem before with other cameras and the problem are bad pixels. When chips are made there is a certain maximum number of bad pixels allowed before QT rejects the chip. More often than not the bad or missing pixels fall outside the field of view. Once in a while they fall right smack in the middle of the picture such as in my case and my camera is only a day old. Of course, Chris could be right and it's just some schmutz. Hey, schumutz happens. __________________ *Ozzie Alfonso* www.ozziealfonso.com

January 20th, 2002, 08:45 AM	#4
Nathan Gifford Wrangler Join Date: Sep 2001 Location: Tickfaw, LA Posts: 1,217	I had the same problem as Chris. Check real, real good too. I found specks on the lens and CCD prism. Nathan Gifford

January 20th, 2002, 10:29 PM	#5
Ozzie Alfonso Major Player Join Date: Nov 2001 Location: New York, NY Posts: 355	Would a speck of dust in the lens or the prism show up as black or white? I don't understand why a white speck would be dust. I'm just asking. I stand to be corrected if there's something I don't know about this matter. __________________ *Ozzie Alfonso* www.ozziealfonso.com

January 21st, 2002, 12:39 AM	#6
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	When the shutter or gain is cranked, a dust speck appears white. Don't know why. What you described sounds like a bad pixel, what Ron described sounds like lens schmutz on the back element. Just gut feelings, not a competent diagnosis, not by a long shot. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

January 21st, 2002, 02:04 AM	#7
Paul Robinson Posts: n/a	Chris is as usualy absolutely right. I Had exactly the same problem with my cam right out of the box. If I remeber rightly it was a blue speck, which is even more perplexing, but I tool the lens off, and there it was. A tiny bit of dust.... Easy to fix really. I thought it kind of rude that a brand new assemble would be soiled though. Paul