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I'm using Canon 700d with 18-55mm and 55-250mm Kit lenses. Somedays my camera manual settings suits the environment and I'm able get some great shots.(Sea shore,Road,Terrace). But sometime I'm getting blurred, dark very poor shots, I tried with shooting many different setting but nothing helps.low-light(Indoor, using flash, evening). While I try to focus a subject it produces a brighter preview image but the resultant image is darker that it shown in preview. How to calculate the suitable aperture, shutter speed, ISO and white balance for the lighting condition and the subject. I do use tripod wherever necessary. Please advise.