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$499 for the 100-400!

Started 5 months ago | Discussions thread
Mike Engles Senior Member • Posts: 2,573
Re: Links to multiple Canon Lens Discounts in the US
1

All texture is in bands of detail, coarse medium and fine. Noise has all all three components and a lot of noise will add it self to all the existing bands of detail in the image.The fine detail is obliterated first and then the mid detail. NR will remove all this mid and fine detail and fills the void with a synthesised false detail (interpolation), that tricks the eye, for a while. What is left is coarse detail, a skeleton of the original, in essence just the bones with no flesh. Once you recognise it, you see it for what it is. Excessive sharpening will just accentuate this.It is a curious thing that adding a small amount of noise will actually trick the eye into thinking that noise is detail. It is called dither and is used a lot in signal processing, both audio and visual.It also obviates the need for sharpening.

The AI Noise reduction programmes look at the image and then try to fill in the gaps with a imagined 'texture'. I had a picture of someone who after I used DXO has a much more hairy nose than they had in real life.

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