Image noise

[stavroshamster]

Hi,
I have been taking some photos today at ISO400 and seem to be getting quite a noisy picture - more than I would expect...
Can image noise increase as a CCD gets older? My 300d is about 4.5 years old now...

[CAT-THE-FIFTH]

I don't see why your sensor should be any noisier than when you first got it!! I would look at using Neat Image or Noise Ninja if you want to reduce the noise in the image.

[Bobster]

post a RAW here and i'll take a peek

i happily took shots @ ISO1600 on my 300D back in the day

[brammers]

Have you changed your post processing software? Especially if you're converting from RAW, this has a massive influence. Going from LR2.5 to LR3 for me is like getting a new camera.

Are your shots underexposed? Noise shows up first in the shadows - highlights hide noise very effectively.

Have you just been looking at too many D3s images lately?

[stavroshamster]

Originally Posted by Bobster

post a RAW here and i'll take a peek

i happily took shots @ ISO1600 on my 300D back in the day

Okay, here are three RAW files.
The first one is taken at ISO400, the second at ISO800, and the third at ISO1600

http://rapidshare.com/files/301307298/CRW_0365.CRW.html
http://rapidshare.com/files/301308917/CRW_9216.CRW.html
http://rapidshare.com/files/301310290/CRW_9233.CRW.html

Originally Posted by brammers

Are your shots underexposed? Noise shows up first in the shadows - highlights hide noise very effectively.

It's definately the noise in the shadows that is bothering me the most. I expect some noise, but what I am getting seems excessive. What do you think??

[Bobster]

ok, so your ISO400 is pretty much spot on exposure wise (you're going to get noise in the shadow - thats just a given, i doubt you'll notice it in print)


the ISO800 is 2 stops under exposed, you could possibly get away with under exposing that much @ ISO400 just, but when shooting ISO800+ on the 300 you need to nail that exposure..


ISO1600, again 2 stops under exposed..


the frist 2 should print fine 9x6, to an untrained eye, you'll get away with the last..

you're shooting a little too fast for motor sports.. 1/125-1/200 is where you should be aiming for..

[stavroshamster]

Thanks.

I guess I should be expecting that much noise then.

It was a really horrible overcast day when those photos were taken and I needed a high shutter speed as I didn't have my tripod and was getting too much camera shake at lower shutter speeds.

Out of interest, how did you know how many stops underexposed the shots were? Does it display that information in the metadata somewhere?

[Bobster]

Originally Posted by stavroshamster

Thanks.

I guess I should be expecting that much noise then.

yes you should expect that much noise when underexposing a shot and then recovering it on a 300D.. ISO800 2 stops under = ISO3200 | ISO1600 2 stops under = ISO6400.. (ISO3200 and ISO6400 coming out of the 300D isnt going to look pretty)

Originally Posted by stavroshamster

It was a really horrible overcast day when those photos were taken and I needed a high shutter speed as I didn't have my tripod and was getting too much camera shake at lower shutter speeds.

you dont need a tripod when photographing motorsports, it takes a smooth panning technique (lots of practice..) and an overcast day will help keep the shutter speed low, i prefer overcast to sunny days when shooting slow shutters (helps keep the aperture low)

Originally Posted by stavroshamster

Out of interest, how did you know how many stops underexposed the shots were? Does it display that information in the metadata somewhere?

i strongly advise that you learn how to read the histogram information that can be displayed on the LCD in your camera, this will help you when shooting

[Blastuk]

Nah, just pull the exposure up until it looks "right"