20D Hot Pixels

Archived from groups: rec.photo.digital.slr-systems (More info?)

Robert R Kircher, Jr. wrote:
> Is it common to have a couple of hot pixels with long exposure shots?
> I was out tonight playing with my new 20D and took a few long
> exposure shots and I see 2 green pixels in the same place on every
> shot. Is this to be expected?

Yes this is quite normal for all digital cameras.

Make sure custom function 02 "Long exposure noise reduction"
is switched on.

-Mike

Archived from groups: rec.photo.digital.slr-systems (More info?)

"Mike Warren" <miwa-not-this-bit@or-this-cairnscarsound.com.au> wrote in
message news:430421ae$0$66795$892e7fe2@authen.white.readfreenews.net...
> Robert R Kircher, Jr. wrote:
>> Is it common to have a couple of hot pixels with long exposure shots?
>> I was out tonight playing with my new 20D and took a few long
>> exposure shots and I see 2 green pixels in the same place on every
>> shot. Is this to be expected?
>
> Yes this is quite normal for all digital cameras.
>
> Make sure custom function 02 "Long exposure noise reduction"
> is switched on.


I figured that it was normal. I thought I had CFn 2 turned on but it
wasn't. Does it make a big difference? and is it something I should just
leave on or only turn on when I'm doing night shots?

--

Rob

Archived from groups: rec.photo.digital.slr-systems (More info?)

In article <430421ae$0$66795$892e7fe2@authen.white.readfreenews.net>,
miwa-not-this-bit@or-this-cairnscarsound.com.au says...
> Robert R Kircher, Jr. wrote:
> > Is it common to have a couple of hot pixels with long exposure shots?
> > I was out tonight playing with my new 20D and took a few long
> > exposure shots and I see 2 green pixels in the same place on every
> > shot. Is this to be expected?
>
> Yes this is quite normal for all digital cameras.
>
> Make sure custom function 02 "Long exposure noise reduction"
> is switched on.
>
> -Mike

Or shoot RAW and use Adobe's RAW processor. Does a great job mapping
out hot pixels.

No one believed me in the past, so here you go:
http://www.pbase.com/image/47865781

But yeah, turning on the custom function noise reduction probably works
better, even if it takes a bit longer.
--
http://www.pbase.com/bcbaird

Archived from groups: rec.photo.digital.slr-systems (More info?)

"Brian Baird" <no@no.thank.u> wrote in message
news:MPG.1d6df25099ceb39698988f@news.verizon.net...
> In article <430421ae$0$66795$892e7fe2@authen.white.readfreenews.net>,
> miwa-not-this-bit@or-this-cairnscarsound.com.au says...
>> Robert R Kircher, Jr. wrote:
>> > Is it common to have a couple of hot pixels with long exposure shots?
>> > I was out tonight playing with my new 20D and took a few long
>> > exposure shots and I see 2 green pixels in the same place on every
>> > shot. Is this to be expected?
>>
>> Yes this is quite normal for all digital cameras.
>>
>> Make sure custom function 02 "Long exposure noise reduction"
>> is switched on.
>>
>> -Mike
>
> Or shoot RAW and use Adobe's RAW processor. Does a great job mapping
> out hot pixels.
>
> No one believed me in the past, so here you go:
> http://www.pbase.com/image/47865781
>
> But yeah, turning on the custom function noise reduction probably works
> better, even if it takes a bit longer.


Actually, I processed these pics through Capture One and the final JPG
didn't show the pixels so I assume C1 also maps out hot pixels as well.

--

Rob

Archived from groups: rec.photo.digital.slr-systems (More info?)

In article <YbudnXR66_N_sZneRVn-vA@giganews.com>, rrkircher@hotmail.com
says...
> > No one believed me in the past, so here you go:
> > http://www.pbase.com/image/47865781
> >
> > But yeah, turning on the custom function noise reduction probably works
> > better, even if it takes a bit longer.

> Actually, I processed these pics through Capture One and the final JPG
> didn't show the pixels so I assume C1 also maps out hot pixels as well.

I would imagine so. It isn't too hard to find and map out hot pixels in
RAW conversion. Just find the pixel that has significantly higher input
values than its neighbors and just average the input.

Why the in-camera processor can't handle that is beyond me - probably
have to wait for DIGIC 5 or something.
--
http://www.pbase.com/bcbaird

Archived from groups: rec.photo.digital.slr-systems (More info?)

Robert R Kircher, Jr. wrote:
> I figured that it was normal. I thought I had CFn 2 turned on but it
> wasn't. Does it make a big difference? and is it something I should
> just leave on or only turn on when I'm doing night shots?

The camera has to take a second exposure for the dark frame
subtraction noise reduction so it takes longer to take the picture.

The user manual should tell you how slow the shutter speed needs to
be before it activates.

-Mike