Size and weight are big decision factors when you are trying to find the ideal camera for your needs.
In this section, we are going to illustrate the Panasonic TS20 and Nikon D90 side-by-side from the front, back and top in their relative dimensions. Panasonic TS20 has external dimensions of 101 x 58 x 19 mm (3.98 x 2.28 x 0.75″) and weighs 142 g (0.31 lb / 5.01 oz) (including batteries). Nikon D90 has external dimensions of 132 x 103 x 77 mm (5.2 x 4.06 x 3.03″) and weighs 703 g (1.55 lb / 24.80 oz) (including batteries).
Below you can see the front-view size comparison of the Panasonic TS20 and the Nikon D90. Panasonic TS20 is clearly the smaller of the two cameras. Its body is 31mm narrower, 45mm shorter and 58mm thinner than Nikon D90. As you can tell, actually this is not a fair size comparison since Panasonic TS20 has a built-in lens but Nikon D90 doesn't. Once you put a lens on D90, its thickness will increase significantly.
Here is the back view size comparison of the Panasonic TS20 and Nikon D90.
Now lets look at the top view comparison of Panasonic TS20 and Nikon D90.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Panasonic TS20 is significantly lighter (561g ) than the Nikon D90 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 D90, the total kit will weigh much higher.
Weather Sealing
Thanks to the weather-sealed body of the TS20, you can use this camera with more confidence under conditions where there is risk of exposure to water and dust compared to the D90.
LCD Screen Size and Features
Nikon D90's 3.00" LCD screen is slightly larger than Panasonic TS20's 2.7" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.