Problematic behavior when image size not in Exif #58
Description
In some cases, image size is not included in the Exif. If Image is called without an image size specified, it will fetch it from Exif.imgsz but not check whether the result is None. Setting Camera.imgsz to None results in the bizarre [-9223372036854775808, -9223372036854775808] due to casting to integer data type, which then causes other issues.