is there something wrong with my camera?

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williamsboldon

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short but sweet, hoping someone can help?!?!

shot a few long exposures t'other day and when i get the images on my pc im happy with the results until, i slightly zoom into the images only to find a lot of red blue and green dots alll over the place, is something a miss with my camera? i fear there may be :(
thanks in advance
 
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^this or dead pixels.
 
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Dead pixels may occur with long exposures, I remember having them with a Fuji S2 some years back after doing long exposures, but only 2 or 3 here and ther if you get me.

Although camera/sensor technology is improving all the time, small sensors, like the one on your Oly will probably produce more noise than say a FF sensor when using L. Exp's or high ISO's
 
Hot pixels, not dead.

Will happen when you do long exposures.

I get 3 or 4 on my 5D mk1.

Get handy with the clone tool or don't do long exposures.

Don't panic that your camera is going wrong, they should only appear on long exposures and not on standard daylight ones, you might be able to find the cut off point for them but this might change as you do them ie it takes a 5 second exposure for them to show up at first but after you've done a few shots the sensor is warm and they appear after 2 seconds. Let the camera cool down a bit and yo go back to getting them after 5 seconds.
 
Maybe chroma noise from long exposure/high iso. Can be removed or dampened in PP, in lightroom there are 2 sliders for noise control.
 
I may be wrong, but I think the OP is talking about noise rather than dead/hot pixels, maybe an image from the OP will help? :)
 
williamsboldon said:
short but sweet, hoping someone can help?!?!

shot a few long exposures t'other day and when i get the images on my pc im happy with the results until, i slightly zoom into the images only to find a lot of red blue and green dots alll over the place, is something a miss with my camera? i fear there may be :(
thanks in advance
Click to expand...

It's long exposure noise, which gets even worse at higher ISO. The smaller sensor of your Olympus is not as good as some, but they all do it.

Did you have noise reduction on? Or reduce it in post processing.
 
heres the image, when put into live photo gallery or PS and zoomed into there are dots everywhere

6226745997_f4d911a0b1_z.jpg
 
Could you do a crop so we can see the dots?

It sounds like hot pixels to me, chroma noise can also be apparent in long exposures but when you get individual dots of very bright colour, that's hot pixels.

Your camera should have a setting for long exposure noise reduction. This isn't like normal noise reduction that just blurs smooth areas to get rid of noise, instead the camera will take a second frame over the same exposure length immediately after the picture is taken but with the shutter closed (that frame will be purely black with only hot pixels and noise), then subtracts it from your picture to remove the hot pixels and pattern noise.

It's very effective and you should always use this setting for long exposures (or do a DIY frame with the lens cap on, then subtract it on the computer for the same effect but without doubling the time it takes to take a pic every time).
 
Faulty / dead / hot pixels.

Clone brush I think
 
Apologies, my mistake in post #8 - that's hot pixels.
 
It's nice being right!

That does seem pretty bad, what was the shutter speed?
 
it's a 4 year old Olympus E-400

it was a long exposure so no shutter speed,with this pic I had the shutter open 60secs
 
williamsboldon said:
it's a 4 year old Olympus E-400

it was a long exposure so no shutter speed,with this pic I had the shutter open 60secs
Click to expand...

I have heard of people running in camera sensor to try and resolve hot/cold pixels, but I've no idea if it really works :shrug:
 
Make sure to turn on your long exposure noise reduction, it really does work for getting rid of things like this.

There's really no reason not to use it.

For a 60sec exposure, that doesn't look much worse than what I'd expect from my 40D without long exposure NR
 
Yeah, 60 is pretty long, when I said I get some on my 5D I don't really go much over a couple seconds ever, I expect if I did a minute exposure I'd get similar.
 
HoppyUK said:
Apologies, my mistake in post #8 - that's hot pixels.
Click to expand...

Me Too!! ;)

But I did say a piccy would help to clarify. :p

Hope you're sorted with an answer now,
Regards.
 
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