[Elphel-support] Global Shutter

[Andrey Filippov]

On Sun, Nov 28, 2010 at 7:30 PM, Abe Bachrach <abachrac at mit.edu> wrote:

> One other question for Andrey/someone else is:
>
> - How much time elapses between when the first and last row are read-out?
>
> from looking at the datasheet, it says that the maximum datarate is 96Mp/s,
> which would mean that for full resolution, the time gap would be at least
> 0.052488 seconds.
>

Abe,

It is somewhat longer than that because of the large "margins", the average
data rate of the sensor running at 96MHz is ~75MPix/sec. There are formulae
in the datasheet that allow to calculate line readout time for different ROI
and decimation

>
> - is the sensor being run at the full 96MHz clock rate? Is that time gap
> number correct?
>

96MHz - yes, correct, but the "gap" is wrong - at full resolution readout
time (and so the delay between the first and last line exposure) is ~1/15
sec

>
> also,
> - How does the subsampling mode effect this. If we put the sensor in
> binning/skipping mode, and downsample by 4x, ideally, this would mean that
> there it takes 0.0032 seconds to read out a frame.
>

Yes, that is correct. Just keep in mind that there is a large "dead" time
(horizontal blanking)  added to each scan line, but small on top and bottom
(vertical blanking)

Andrey
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