PBase

Please help me...
I took this picture on a shutter speed 60sec ... ( Blub)... by the Nikon D300 ... with ISO:100
What are these dots that are showing in this picture? ? is it just dust ?? or another thing??
So is the sensor damaged? or its just dust?
http://img375.imageshack.us/my.php?image=dsc69561jw9.jpg

I vote for dust... If you had shot a longer exposure I would change my vote to noise generated by the long exposure time.

With a shutter speed of 60 seconds they look like hot pixels IMHO, not too surprising for a long exposure. Check your camera manual and see if you have an option for dark frame subtraction or noise reduction using second frame subtraction - not another noise reduction mode. Most DSLRs have this to eliminate what you see. Basically a second frame is exposed with the same ISO & shutter speed but the shutter stays closed, this is then subtracted from the photo. This can do a good job correcting some types of detractions, the downside is it takes the same time for the dark frame as it does for the photo, so it takes longer, and it will only correct for hot pixels, etc. that are consistent & repeatable from shot to shot.

Oh jeez, I hate those blasted pop-up ads the shack has, but anyway...

I agree 100% with Doug. Dust shows as dark spots, usually on lighter areas, and not colored pixels. I'd imagine prinothcat was thinking 1/60th.

prinothcat wrote:I vote for dust... If you had shot a longer exposure I would change my vote to noise generated by the long exposure time.

OOH I'm in need of reading lessons it appears... I miss read 60 sec for 1/60... duh....
So can I change my vote to noise? The hot pixel idea has merit as well.

LOL - The only reason I might have gotten it right is because I was wearing my reading glasses....and read it a few times. My replies can be rather comical when I don't wear my glasses. Your new vote has been duly recorded Chris

If they are hot pixels then you should return your camera under warranty - 60 secs is not long.

If you want to check it:

Leave the lens cap on, Switch to Manual, expose for 60 secs. You will end up with a black exposure and the hot pixels will stand out. If there are just one or two, this is common, but if there are lots, you should definitely get it checked.

It's common for hot pixels to appear with shutter speeds below 60 seconds, it's a question of how many and if the manufacturer will exchange the camera or remap the defective pixels. You can try the test cmit described and visualize the results.

dougj wrote:LOL - The only reason I might have gotten it right is because I was wearing my reading glasses....and read it a few times. My replies can be rather comical when I don't wear my glasses. Your new vote has been duly recorded Chris

I made my first concession to be not young this am...
Yep reading glasses. I turn 45 in about a week.... wish me luck.

Definitely "Hot Pixels." Google the term and you can get a pretty good explanation of the anomaly.

I agree with the above... hot pixels!
Easy enough to clone out - but I would take camera back to retailer.

These are HOT pixels.

When you go for long exposures then turn NR on.

....maybe hot pixels caused by cosmic radiation.

Call Nikon themselves. I have always found them to be helpful. I have the same camera and have never had those spots. They do seem like mistake.
Caryl

I'd say hot pixels.

Also, the EXIF says it was 76 seconds -- not that should make a huge difference, however.