On 17/01/2019 11.17, Whisky-dave wrote:
On Wednesday, 16 January 2019 15:55:48 UTC, nospam wrote:
In article ,
Whisky-dave wrote:

It is two separate exposures on the same frame. Which is what a digital
camera does not do, so it is not double exposure.

it's two separate exposures in the same memory, before it's written to
a raw or jpeg image, thereby making it a double exposure by any
definition.

No it wouldn't, as it would be in the same 'memory' as that would require
complety overwriting the information from the previous exposure.

no.

yes, you obviously dont know much about electronics down to that level.
Itls digital remmeber either a 1 or a 0 unlike film.

That's correct. Each memory position, corresponding to a pixel, has to
be read, its value added to the new value from the sensor or other
memory map, then written back to the memory, or to another memory map.
The CPU has to intervene.

That's not much different from adding to images on file on the card, and
thus not much different from doing it on the home computer.

And of course, it can be added or any other more complex operation the
programmer puts there.


Very different from exposing the sensor twice before reading it, which
would be similar to what is done on film. I don't know if that is
doable, the sensor could lose the information in the interval. And
anyway, pointless, except for the sake of saying "I did it!". Better
use digital cameras in new digital era methods.


--
Cheers, Carlos.