CCD sensitizing ( how operates long time exposition ? )

[andre_luis]

CMOS Camera module sensitizing ( how operates long time exposition ? )

hi all


When we change shuttler value fom miliseconds to seconds, how it works digitally ?
Frames acquisition occurs at a constant rate, or the exposition time to sensitize camera cell really is higher ?
My doubt is know if it is done digitally ( adding acquired sucessive frames ) or if sensibilization occurs at shuttler time.

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[jpanhalt]

Check here under "architecture" :Charge-coupled device - Wikipedia, the free encyclopedia

Apparently shuttering is done in different ways depending on the type of CCD.

John

 

[andre_luis]

Ok,

But what I did not understand is if all frames are added digitally.

"...To counter such effects, astronomers take several exposures with the CCD shutter closed and opened..."

The application in wich I´m refering will need some seconds to exposure.
However I did not found explanation about word magnitude of A/D converted pixel read (8bits ? /12bits ? / etc...).
I believe this method off adding stacked frames inserts a small ratio SIGNAL/NOISE, due each acquired values are not high.