This is a tip which was posted by Papa.
I thought it would be good to kick off this new thread.
I hope you don't mind Papa,let me know if I have got anything wrong.


NOISE REDUCTION PHOTOSHOP

Prepare your image to its full potential, leaving sharpening to the very last.
Resize ready for web display.
1...On the very top of your Photoshop page select LAYER then flatten image.
2...On the very top again select IMAGE mode,8bits?channel.
3...On the very top again select Layer, duplicate layer. It will save as Background Copy.
On the LAYERS PALLET on the right hand side you will now see 2 small images labelled Background and Background Copy. The Background Copy will be highlighted.
4...On the top go to FILTER,blurr,surface blur.
A new box for the Blur will come up ,make the radius 100 and the Threshold 5.
Look at the panel showing your 2 layers on the right hand side, above these you will see OPACITY click the drop down box and use the slider whilst looking at the main image and adjust to suit your particular shot.
You will notice that only the out of focus areas of the image will be affected as this is where the noise is.The subject which is in focus will have very little or no noise.
In the LAYERS PALLET To the left of your background copy you will see an eyeball, click this on and off whilst looking at the main image and you will be able to see if your main subject is affected by the blurr.
If it is affected you can paint over this to rub out the blurr affecting your main subject.
5...If you look at the Layers pallet on the right, at the very bottom, click the 3rd icon from the left.
A square with a dot in the middle.
This will bring up a white box next to the picture on your Background copy.
Next look at the vertical tool bar on the left and 3rd from the bottom you will see 2 squares which should be black and white.
Put the black square on top, select a paint brush and at the right hand side click on the white square which is showing in your background copy.
Go over the areas on your main image with the brush that you don't want the blur to affect.
The area you paint will show up on the white square on your background copy layer at the right hand side as black.
6...At the very top go to Layer, flatten image....JOB DONE


FINALLY SAVE YOUR IMAGE

Alan