underexposure/noise?

[holland]

In so many of my images I get this pattern, particularly in skies. Is it underexposure and the noise that results from the dark areas? Or is it something to do with the white balance? Or RAW processing (I always take in RAW and use Canon software to convert to 8-bit tiffs).

Would be grateful for any suggestions how to prevent this and rectify images containing this. When printed out on a professional inkjet it can't be seen (something to do with continuous tone?), but when done on glossy fuji archive paper it is printed like this and it looks bad.

It's a Canon 10D and taken almost 40,000 photos - is the sensor getting tired?

Any help gratefully received (particularly practical advice on how to correct it for printing and how to avoid it in the future). Many thanks, Alex.

[tim]

That looks like luminence noise to me. What ISO was it taken at?

[robertwgross]

You know that you will get some degree of color noise or luminence noise in every image. The higher in ISO you go, the more of it you will see.

If you convert RAW to 16-bit TIF, it might be somewhat smoother. Alas, many editing tools will not work fully on 16-bit-per-color-channel stuff. Some do, though.

There are many tools for smoothing that image problem.

---Bob Gross---

[holland]

Taken at ISO 100 - I always shoot on the lowest to avoid noise, but get this instead!

Which tools would you recommend using to smooth the image?

Many thanks for your responses.

[foxbat]

Imagenomic Noiseware Professional. It really is like having a "make this photograph look great" button in PS.

[PhotosGuy]

RawShooter has noise reduction tools built in.

[holland]

Wow! Imagenomic Noiseware Professional is very good. That's just the thing to correct all my images. Many thanks foxbat.

[drisley]

I wouldnt think you would need any noise removal on an ISO100 image

[holland]

I think it is more to do with underexposure as it appears as a grainy texture in the sky and darker areas.