ViewSonic PJ452 Service Manual - Page 29

6-9 Notice of AUTO adjustment Use of AUTO adjustment with the image through RGB input optimizes V_POSI, H_POSI, H_SIZE and H_PHASE automatically. In case that projected image has dark tone around its peripheral, AUTO operation sometimes makes artifacts in the image, shifts capture area and so on. Those failures are caused by period of image data is not exactly distinguished to period of blanking on signal processing. To avoid such phenomena, AUTO function should be used with the full size picture that has bright tone on its peripheral. Image when AUTO operates correctly Image when AUTO fails. Noting image of top or bottom lines. Shift of the image to East or West. Artifacts on image. Etc. Note 1) The phenomenon at the failure of AUTO adjustment depends on resolution of input source, scene of pic- ture etc. 2) There is no failure above in AUTO with video source through VIDEO, S-VIDEO or COMPONENT input. The reason is why recognition of input signal's standard does not need to search the capture range from input signal itself. ViewSonic Corporation Confidential - Do Not Copy PJ452 26