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Cooling e2v EV76C661 sensor

Limiting noise in EV76C661 based machine vision - planetary camera

I reviewed IDS Imaging UI-1240ML-NIR-GL camera equipped with EV76C661 sensor. When using high gain and longer exposures around 30 ms for Saturn dimmer channels the noise - hot pixels were quite apparent. On rolling shutter the noise (at least read noise) should be low. So most of the visible noise should come from dark current. To check that I've cooled the camera using a fridge to few deg below zero. Below you can see how the noise lowered when the camera cooled from ambient 20C to around 0C (39.46ms exposure, gain 355 - max).

Cooling effect on Ruby EV76C661 sensor total noise

A Peltier cooled camera would be very desirable. It would allow easy Neptune and Uranus imaging at much longer exposures (or Jupiter methane band) without overwhelming noise. Saturn would like that too. Plus maybe some DS imaging if it would handle ~5 min exposures at low noise.

As global shutter gives a lot of noise even when cooled we can look at EV76C660 which works only with rolling shutter and offers on the paper even higher sensitivity and only ~3e read noise. However those sensors aren't available in machine vision cameras - either due to rolling shutter or they are just unavailable on the market. I would really wan to see a cooled camera with such sensor. Even for planetary imaging the shutter isn't perfect but it seems to work if the conditions aren't bad.


25 August 2013;

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