Weight of digital pictures

[little B]

Does your camera weigh a different amount when you have taken pictures? 2 things to answer here - does the change in data storage affect weight, and does the battrery lose weight.

[Clanad]

Interesting question, but, no, the camera or, more accurately, the storage device does not increase in weight. Through a system within the camera called a CCD, Charge Coupled Device which converts photons into electrical charges (photons have no mass, but do have momentum that is not proportional to its mass but, rather, to its frequency) and the process continues digitizing the electrical energy into the usual series of "1''s" and "0's" common to all computer processors. These are, in the final analysis, what's stored on th eflash drive...

[matt_london1]

I would say that it does lose weight due to the energy used up in the battery. e=mc^2 and all that!

[beso]

matt is absolutely correct. Einstein's energy to mass relationsip applies universally. A discharged battery has a lower mass than a charged one.

If the battery holds say 5 Watt hours (18 KJ) the difference in mass between charged and discharged states will be 20 nanograms. One thousand millionth of a gram. ie not much.

The change in randomness due to information contained in the memory does not affect mass.

However the information is stored as electric charge on the gates of transistors in the memory. There is a change in mass as the electrons are added or removed to store the bits. The mass increases or decreses depends on the how the information is written and the "blank" state of the memory. (Rather like the difference between black writing on a white background or vice versa.)

The technology of flash memory is quite well described at
http://en.wikipedia.org/wiki/Flash_memory

[Clanad]

However, computers use binary systems, in which data is stored as "zeros" and "ones". A "zero" is simply represented as a different voltage than a "one", and
there is no change in mass or weight of a computer system depending on the number of "one's" and "zeros" in the data. The storage device in the camera is utilizing the same type of voltage differential to store the "ones" and "zeros" representing the photograph...