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 Sony NEX-5T and Panasonic ZR3 side-by-side from the front, back and top in their relative dimensions. Sony NEX-5T has external dimensions of 111 x 59 x 39 mm (4.36 x 2.31 x 1.53″) and weighs 276 g (0.61 lb / 9.74 oz) (including batteries). Panasonic ZR3 has external dimensions of 98 x 55 x 26 mm (3.86 x 2.17 x 1.02″) and weighs 159 g (0.35 lb / 5.61 oz) (including batteries).
Below you can see the front-view size comparison of the Sony NEX-5T and the Panasonic ZR3. Panasonic ZR3 is clearly the smaller of the two cameras. Its body is 13mm narrower, 4mm shorter and 13mm thinner than Sony NEX-5T. As you can tell, actually this is not a fair size comparison since Panasonic ZR3 has a built-in lens but Sony NEX-5T doesn't. Once you put a lens on NEX-5T, its thickness will increase significantly.
Now lets look at the top view comparison of Sony NEX-5T and Panasonic ZR3.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Panasonic ZR3 is significantly lighter (117g ) than the Sony NEX-5T 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 NEX-5T, the total kit will weigh much higher.
Weather Sealing
Unfortunately neither the Sony Alpha NEX-5T nor Panasonic Lumix DMC-ZR3 (Lumix DMC-ZX3) provides any type of weather sealing in their bodies, so you have to give extra care especially when you are shooting outdoors. If weather sealing is a must-have feature for you, check these sections: Top Mirrorless Cameras with Weather Sealing Top Compact Cameras with Weather Sealing
LCD Screen Size and Features
Sony NEX-5T's 3.00" LCD screen is slightly larger than Panasonic ZR3's 2.7 screen.
In addition to the size advantage, Sony NEX-5T LCD screen also has a
Tilting feature where you can change the angle of the screen to make it easier to shoot from waist or over-the-head levels. On the other hand, Panasonic ZR3 has a fixed type screen which provides less flexibility in shooting positions compared to NEX-5T.