What is this?

Paul870

Paul870

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Edit My Images
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Out shooting tonight on the dock front in Liverpool, and it seems on pretty much all of my images has these two red dots in exactly the same place. Can anyone shine some light on to what it is?

Picture showing it:

 
I thought it was my monitor at first, but theyre not on my screen on an all white image.
Can camera bodys get dead pixels? Abit worrying as im not sure what it is! Images I took last night did not have them, although today they do?
 
How long was the exposure, long exposures can show up this far more than short/standard exposure times
 
Having said that they are lovely sharp photos, I cant even see the spots youve circled
 
For that image the exposure was 30 seconds, however these red dots have appeared in shots that were 3.2 seconds, but on a few shots that were 1/5 - 1/6 they are not there.

Thank you Tony :) my first night of shooting full manual!
 
They could be 'hot pixels' ?

There's lot's of info if you google it for when and why they might be visible/more visible.
 
They're Hot Pixels, which is why they are only appearing on long exposures.
 
It's not just the 'length' of the exposure that will bring them out - increasing the ISO will make them visible/more visible. Dark backgrounds don't help either and by all accounts temperature too.
 
from a quick google in seems a hot pixel is in fact a defect of the camera body, my 500D is still under warrenty, is this something that is permnament, or will it go away?

Camera has only done 3000 clicks!
 
It's to do with the sensor and they may come and go depending on the factors mentioned above (Exp length, darkness, temperature, ISO)

When you're pushing these factors a lot of cameras will 'show' hot pixels yet not show them at other times.

If you're getting them under 'normal' conditions then I guess it could be a pain. Do you shoot RAW ?. I think the RAW conversion will wipe them out but I could be wrong.
 
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Try putting your camera into sensor cleaning mode with the lens on for a few minutes. Usually fixes it.

If it doesn't work the first time, try it again. :)
 
I think it's quite common to have hot pixels with cameras, especially in lower lighting conditions where the darker image is more likely to show them and where the camera has to expose for a longer period. My camera has them and I removed them by putting the camera in manual cleaning mode with the camera cap attached for 30 seconds. This should map out the worst ones.
 
Given that most cameras these days have sensors that contain more than 12 million pixels, even with the best quality control possible, it's not entirely unusual to have a couple of hot pixels on even a brand new camera.

As others have said they will usually only show up on certain types of pictures, or pictures taken under certain circumstances i.e. long exposures and/or dark areas in the image. One saving grace is that quite a few cameras have the ability to map these pixels out so that you don't have to do it manually in PP. Have a look through your camera manual to see if you can do this on yours.
 
Advice taken thanks all!been out today and no pixels have appeared, suppose that was the only benefit from today as the weather has been so dull all my images were for the bin!
 
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