I am new to Drupal Commerce and having problem in retrieving product image from product object. I am doing commerce_product_load(product_id) for getting product object. Although I have stored image while creating the product but still the field_image array is empty.

I tried to get product object in two ways:
First, using line item wrapper I retrieved every line item object and using the line item object I retrieved product ids and finally their product object. In this case the field_image array was not empty.

Second, I used commerce_line_item_load(line item id) to create a line item object and retrieved product id from the line item object. Finally product object from product id. In this case field_image array was empty.

Does product object also depends on the line item object? Do I always have to load product object from line object obtained from line item wrapper?