deffects of photos - how to remove artifacts

Artifacts are the little bits of digital noise that you can spot in magnified digital images in areas of shadow or large areas of even colours (a big blue sky for example). Below there are two photos. First photo have visible in magnification artefacts and second photo is after get rid artefacts. If we reduce them with the reduce noise filter in the Photoshop not only remove the noise, but also reduce details. There are many programs for reduce noise better or worse but all ones have this defect. How there can avoid of it I found on site of Dave'a - American photographer . There is link to this site Photos4u2c . I must admit that isn't too easy used his method but effect was admirable. Now I use his way very often even when artefacts aren't too visible.

You can see result when you peer at left side especially at left bottom corner. It will be more visible when you will copy photos and peer in your browser in magnification.