An apparatus and image reconstruction method for use in an apparatus including a digital camera are provided. The apparatus and method include driving an image sensor during a short exposure time in an image reconstruction mode, driving the image sensor during a relatively-long exposure time in the image reconstruction mode, and acquiring first and second frame images having different illumination degrees; assigning substantially identical image data of the first and second frame images to local images each having a predetermined size; calculating local variance values of image data of each of the local areas; comparing a local variance value of the first frame image with a local variance value of the second frame images, assigning a high weight to one local image having a high local variance value, and assigning a low weight to the other local image having a low local variance value; applying the determined weights to image data of individual local areas of the first and second frame images, performing image reconstruction, and displaying a reconstructed image.