Techniques for Removing Noise

[Dizzy]

A few weeks ago I posted a photo which contained lots of noise due to the time of day (close to midnight) and the need for ISO 400 setting. The photo can be seen at http://www.trekearth.com/gallery/photo282867.htm

Jeppe introduced me to Neat Image for reducing noise and I experimented with it on the photo. I found it to be very effective but it will take me a while to be able to use it properly.

This particular photo has all the ingredients for anyone wanting to practice, or demonstrate, their noise reduction techniques and I would welcome any comments or workshops on it.

Thanks.

David.

[Imran]

What kind of noise was there in the picture

[Dizzy]

Sorry, I don't know how to describe the noise. Are there different sorts?

It was mainly in the water but also in the sky. I gave a link to the photo - perhaps you could take a look at it?

[kajenn]

David,

I saw your request some time ago and made a WS using NeatImage on your image. Unfortunately I didn't have time to upload it until now, as the process needed a thorough description.

But now it's there - go have a look...

Best regards,

Kaj

[Aido]

Hi David,

As well as Neat Image you might want to take a look at the jpeg repair function of Alien Skin's image doctor. It's great for removing noise from digital images without degrading the image too much.

Adrian

[Dizzy]

Thanks to both of you, Kaj and Andrew.

Kaj, I've now studied your workshop. You have brought back some life into some of the waves, the sky and the on-shore rocks. On the other hand, I think the USM (which I am just starting to get the hang of in PSE2) may have given a little too much sharpness to the lights and their reflections in the water, also to the "ColorLine" on the side of the ship.

Of course, I have the advantage of being there at the time and remembering the scene quite vividly. We don't get night light like that in the UK!

The other thing I notice is that what I thought was noise in the sea, especially on the left hand side, is still there. It was this noise that I had unsuccessfully tried to eliminate without ruining the rest of the image. Perhaps this is asking too much of image managing software?

The bottom line is that I very much appreciate your workshop and notes and will study these in more depth in the next day or two. It is now midnight here and my bed calls!

Many thanks.

David.

[AdrianW]

The problem with your image is that it contains both fine detail and fine noise - there's no way for the software to readily determine which is which.

So, that's where the human element comes in :)

In this image I'd load the NeatImage/Noiseware/NoiseNinja picture in as a new layer on top of the un-edited one - and then use a soft-edged eraser at (say) 15% opacity to gradually knock out the areas of the image you don't want to apply noise-reduction to.

Looks like the areas most in need of cleanup are the sky above the ship, and the pebbles on the foreground - so use the eraser least there.

Hope that helps!

[PixelTerror]

From the example it seems to me the noise is resulting from shooting at high ISO with the Panasonic FZ20 camera, on the Neat Image web site there is a profile specific to this camera that could possibly have improved the view a bit.
A lot of profiles are available for a wide range of cameras.

[Dizzy]

Jean Yves, thank you for the tip. I had spent a long while in the Neat Image website but managed to miss the page about the Profiles!

[Dizzy]

Thanks, Adrian. I'll try that technique. It's all useful experimentation.