A watermarking field is necessary to prove the copyright, ownership, authenticity and other related security aspects of the electronic data. Semi-Blind watermarking refers to need the watermark image during the extraction process. While, informed watermarking generates the watermark data from the original image itself. Moreover, Tamper detection is useful to discover the tamper zone in the image. In this paper, we propose a semi blind and informed watermarking approach. We build the watermark from the original image using Weber Law. Our approach aims to provide a high robustness and imperceptibility with perfectly tamper detection zone. We divide the original image into blocks and the main pixel is chosen for watermark insertion, where the embedding/extraction operates in the spatial domain. The tamper detection is tested by tampering watermarked image, and then based on the extracted attacked watermark; we can discover the tamper area. Also, the robustness watermarking aspect is proved against different kind of geometric and non-geometric attacks. Based on the experimental results, the imperceptibility and robustness of our watermarking approach are proven and showing perfectly the detection of the tamper zones.