Lab Mode for Noise Reduction :-)

[wll]

My new method for removing noise seems to work better than anything I've tried so far.

I'm using Lab Mode and separating the color channel from the luminosity and getting great results.

Anyone else use this method ?


wll

[Quension]

What is Lab Mode?

[song_hm]

I've read of using Lab Mode for sharpening, but not for noise reduction. Care to explain the process?

[thazooo]

I process in LAB. I'm curious about how you're doing this. Which channel (s) and who's noise plug-in are you using.

[jeffkrol]

Originally Posted by Quension

What is Lab Mode?

A colorspace in which to work in. It has 3 "channels" L= lightness" a= green to red
b= blue to yellow
Lab color space - Wikipedia, the free encyclopedia
Really more than anyone needs to know......
http://www.fho-emden.de/~hoffmann/cielab03022003.pdf

[jpzk]

I would also be interested to know how your Lab work for noise reduction ... works! I use Lab Colour for sharpening purposes, then back to RGB. It does a great job with keeping the colours intact once processed that way.
JP

[wll]

Here it goes:

Image>Mode>select Color Lab
Then go to
Window>Channels

Select a channel

Go to Filter>Noise>Median
Examine a Channel and then blur

Select b channel

Choose Filter>Noise>Median
Examine b channel and then blur

Choose lab composite channel at top of channels palette to return to regular color view

Examine image and save.

If you blur just enough to blur noise, color and image sharpness will be saved and you will have very good low noise reduction (within reason) image. I found this better and easier than the noise reduction software on the marker today.

This info was from PhotoShop CS for Digital Photographers by Colin Smith.

Hope this helps my fellow shooters.

wll

[tlwyse]

A pretty common method of reducing noise in Lab mode is to apply Surface Blur only to the a*/b* channels but not L*. Since the a/b channels are only color (not Luminosity or "detail") you can be pretty heavy-handed with Surface Blur and not affect the image. This technique mostly reduces color or chroma noise but not luminance noise.

Regards,
Terry Wyse

[Quension]

Originally Posted by jeffkrol

Originally Posted by Quension

What is Lab Mode?

A colorspace in which to work in. It has 3 "channels" L= lightness" a= green to red
b= blue to yellow
Lab color space - Wikipedia, the free encyclopedia

Thanks, and the following posts finally made it clear this was (mostly) about using Photoshop. I was trying to figure out if "Lab Mode" was the name of a software package or something...

[thazooo]

Thanks for the info.

[jeffkrol]

Originally Posted by Quension

Thanks, and the following posts finally made it clear this was (mostly) about using Photoshop. I was trying to figure out if "Lab Mode" was the name of a software package or something...

16bit L.A.B. is also available in Corel Photopaint (cheap plug for my favorite PC software and a minor blow against the Adobe juggernaut)

[thazooo]

Originally Posted by jeffkrol

16bit L.A.B. is also available in Corel Photopaint (cheap plug for my favorite PC software and a minor blow against the Adobe juggernaut)

Another Corel User, cool . I'll ditto on the 'minor blow' against adobe :-)

[jeffkrol]

Originally Posted by thazooo

Another Corel User, cool . I'll ditto on the 'minor blow' against adobe :-)

Pentax brand (underdog) users should use underdog software. Only logical..
Interesting site:
Graphics Unleashed - CorelDRAW and Corel PHOTO-PAINT - Tutorials, Training, Books, Videos

[thazooo]

Originally Posted by jeffkrol

Pentax brand (underdog) users should use underdog software. Only logical..
Interesting site:
Graphics Unleashed - CorelDRAW and Corel PHOTO-PAINT - Tutorials, Training, Books, Videos

Thanks for the link. It's good to see some independent sites showing up
for Corel Graphics. When I need some info or just to browse I go here:

Home - CorelDRAW.com

It sure beats the old news group

[Parallax]

I use that method also. I have the Neat Image plugin and it works great.