Uh oh... Red Pixel ???

[dschwartz69]

Can anyone suggest what might be causing the red pixel in the photo, below:

http://members.cox.net/dschwartz/redpixel.jpg

It is a crop of a 100% jpg.

Any ideas? anyone seen something like this before? It appers to be in every photo at the exact same spot, no matter what the zoom focal length - so it is not something on the lens itself, I don't think?

help?

[drisley]

That is a hot pixel.
Hot pixels are fairly common on cmos sensors, but are usually only visible at high ISO and/or long exposures.
Was that the case with this shot?
If so, it's nothing to worry about. If it shows up on ALL pictures, even faster than 1 second exposures, then you might want to have it looked at.

[dschwartz69]

This shot was:

ISO 100
F/8
30 sec. exposure
48mm

Canon 10D with 28-135 on tripod

[defordphoto]

Use the heal tool.

Hot pixel gone.

[dschwartz69]

Sorry, I'm a newbie to this forum - 'heal tool'?

If referring to a software to remove pixel, I can do that in Photoshop CS; I'm more concerned about a possible hardware issue with the camera itself?

[tpinchback]

Yes photoshop will have the heal tool.

The hot pixil is very common on all digital cameras. I have about 8 on my digial camera. When you are talking about 6,000,000 pixels, to have a few that are dead will no hurt anything, but you will need to spend an extra minute in the digital darkroom.

[dschwartz69]

Thanks for the tip on the heal tool - I'd always used the stamp tool in the past but was never very pleased with the result; now I know why.

[drisley]

Is that a crop?

For a 30 second exposure, it is not at all uncommon to get atleast 1 hot pixel like that. It's normal, don't worry.
Temperature will affect hot pixels as well, as they usually show up more in hot weather.

If you go to almost any camera review site on the web, and look at full-size pictures of longer exposures, you will often see atleast one or two red or blue hot pixels.

[dschwartz69]

yes, it is a crop, but I thought I left it at 100% (i.e. not enlarged at all). At home when looking the original (not the webified version) you can see the red spot is exactly one pixel (I have also just noticed a blue one near the bottom of the same pictures).

It was also warm out (i'm in Phoenix, AZ - it was probably about 100 or so when I took the photo.)

[drisley]

yup, that's totally normal.
I have one hot/red pixel on my exposures longer than a few seconds.
However, sometimes if it's cool, it doesnt even show.
I was just looking at some 300D samples from DP Review, and I can spot atleast 3 hot pixels in their long exposure tests.

[robertwgross]

It was also warm out (i'm in Phoenix, AZ - it was probably about 100 or so when I took the photo.)

Yes, but isn't that a dry heat?

In the future, if you have to take another 30-second exposure, try to rig up some way of keeping your camera cooler, just to see if that will make any difference.

---Bob Gross---

[BearSummer]

Hi dschwartz69,

Next time you are using the long exposure settings, when you have just about finished, put the lenscap on and shoot a blank frame with the same settings as you have been using. If you do this at the end of the shoot when the camera has "warmed up" then you will easily be able to see which pixels are hot against the black background. This means that you will know where to look on your pictures and it will be easier to rotouch the hot pixels.

best regards

BearSummer

[Penguin_101_1]

Now that you have answers to get rid of it why not use it.

Showing picture to people at work:
" I was taking this picture and then this UFO came. It was just like the one on the movies, little and red with little green people. See it there on the picture." :wink:

[dschwartz69]

Everyone - thanks for the suggestions and reassurance. I was a bit worried by camera was on the fritz and was already envisioning a two-month round trip to some cold, sterile Canon service center somewhere.

Whew...