Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate FujiFilm S2800HD and Sigma SD1 Merrill side-by-side from the front, back and top in their relative dimensions. FujiFilm S2800HD has external dimensions of 110 x 74 x 82 mm (4.33 x 2.91 x 3.23″) and weighs 437 g (0.96 lb / 15.41 oz) (including batteries). Sigma SD1 Merrill has external dimensions of 146 x 113 x 80 mm (5.75 x 4.45 x 3.15″) and weighs 790 g (including batteries).
Below you can see the front view size comparison of FujiFilm S2800HD and Sigma SD1 Merrill. FujiFilm S2800HD is 36mm narrower and 39mm shorter than Sigma SD1 Merrill but it is also 2mm thicker. As you can tell, actually this is not a fair size comparison since FujiFilm S2800HD has a built-in lens but Sigma SD1 Merrill doesn't. Once you put a lens on SD1 Merrill, its thickness will increase significantly.
Here is the back view size comparison of FujiFilm S2800HD and Sigma SD1 Merrill.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
FujiFilm S2800HD is significantly lighter (353g ) than the Sigma SD1 Merrill which may become a big advantage especially on long walking trips.
Again, this comparison may not be very useful in real life as we are comparing the weight of a camera with a built-in lens to the body-only weight of an interchangeable lens camera. Once you put a lens on SD1 Merrill, the total kit will weigh much higher.
Thanks to the weather sealed body of SD1 Merrill, you can use this camera with more confidence under conditions where there is risk of exposure to water and dust compared to S2800HD.
LCD Screen Size and Features
FujiFilm S2800HD and Sigma SD1 Merrill's LCD screens has the same diagonal size of 3".
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.