Sensor size is most noticeable in low light (without flash).
It shows up as noise (a grainy appearance most noticeable in dark areas).
When comparing it is also important to know the shutter speed, f-stop and ISO setting.
f-stop determines the depth of field.,
a high ISO (ie 1600) setting is usually noisier than a low setting (ie 100).
Shutter speed is important if you have movement of something in the picture. The higher the shutter speed the more light is needed.
Here is a one-to-one comparison of the two cameras.
To see the specifications of each, click the specifications title.
To compare images on the computer screen, show the image at full size.
For scenery check the grass leaves and tree leaves.
Poor resolution will show up as blurry, smudged or soft leaves.
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I own a Panasonic FZ35 for a few years. Recently I bought a Sony NEX-5T, since I noticed the sensor used in NEX-5T is about 10 times large as the sensor used by FZ35. I tried to compare two cameras. I tried low lights, near distance, far distance, etc. Most time I used a tripod with 2 or 10 seconds delay so that there was no hand movement involved. I tried automatic, P, A, S, M options. I was surprised that there were no noticeable differences between two sets of pictures. I even showed my co-workers those two picture sets (blindly). They also said the difference was minimal. Anybody here can help me how should I compare those two cameras, or just tell me the sensor size does not really matters and why. Thanks.

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