Question about acquisition rate

[Jean-Yves]

Hi,

I have a DFK31AU03.AS and am confused about its acquisition rate:

I set Video Format Y800, Codec Y800, FPS 30, Gain 600.

- If I set Exposure as 1/30 s, then the software acquires 27 images per second

- If I set Exposure as 1/15 s, then the software acquires 10 images per second

Why so few FPS at 1/15 s?
I image Jupiter in color at f30 and 1/15s is the rate that gives me the best results (Registax processing) but the frame rate is too low, what can I do?

Thank you

Jean-Yves

[Sascha Schmidt]

First of all, it is very possible that you have frame drops.
This explains the 27fps at a Exposure of 1/30 s.

If the exposure time is greater than the frame rate, the camera switches to 'long exposure mode' and does not parallel deliver and expose frames.
This means, that at 30fps and a Exposure of 1/15 s, the camera needs 1/15 s to expose and 1/30 s to deliver the frame.
Therefore you have only 10fps with these settings ( 1/15s + 1/30s = 1 / 10s ).
In order to avoid this, simply select 15fps and a Exposure of 1/15 s. Then you will have about 15fps.

[Jean-Yves]

Hi Sascha,

Thank you very much, it works:
- If I set 30 FPS at 1/15s, the system records average of 9.5 FPS
- If I set 15 FPS at 1/15s, the system records average of 14.3 FPS

Cheers

Jean-Yves