Originally posted by subhuman
WHAT actually are hot pixels??? Hehehe..
also i understand Olympus DC has major noise problems... what's the cause of this?
http://forums.clubsnap.org/showthread.php?s=&threadid=7791
Because I am actually very tempted by C-730 if the Olympus promo for only $599.00 actually happens.
What is a hot pixel!!?? Ok you can either follow the first link on the post you have in your message or you might read on
As all electronic devices, the CCDs used in digicams also have what is called a leakage current. And when you expose the CCD to light or just keep in on for a few seconds, the leakage from some pixel or the other will be so great enough that it tells the picture processor that there is a brigh pixel. When a lot of pixles exhibit this phenoenon, your picture will be full of 'stars'. This is called hot pixel problem.
It is not exactly a defect but rather a shortcoming of digital cams.
That is the reason you will not find exposures as 4Hrs etc. on digicams which you can find on film cams. Most consumer digicams have a maximum exposure of a few seconds.
Now that we know this, it is not really difficult to remove those 'stars' with post-processing.
Considering the noise problem, ALL digital cameras have some amount of noise at higher ISO settings. Increasing the ISO setting is actually amplifying the CCD signals more and more. The more yu amplify, the more you distort the singnal and hence you have noise. This is smilar to te noise you hear when you hear at maximum volume of your 1980's tape recorder. More the amplification, more noise.
Noise IS an inssue with most consumer digicams but I am not really sure if Oly or canon or whoever else is better in this issue.
Can some experts comment on this?
