Specifications

target temperature is displayed in cyan color on the graph. The current chip

temperature is displayed in red. Also notice the blue line, which displays the

cooling utilization – it starts to grow from 0% to higher values.

Also notice the yellow line in the graph – it displays camera internal

temperature. This temperature also somewhat grows as the cooling utilization

grows. The hot air from the Peltier hot side warms up the camera interior

slightly.

How fast can be the chip cooled? Can be the chip damaged, if it is cooled too

fast? Unfortunately the maximum speed of temperature change is not defined

for Kodak CCD chips (at last the author does not know about it). But in general

slow temperature changes cause less stress to electronic components than rapid

changes. The SIMS temperature change speed default value is 3 °C per minute.

It is usually no problem to switch the camera earlier and to provide time for

slow cooling. However, if it is necessary to cool the camera rapidly, alter the

“Max. dT” value.

It is also easier to achieve higher temperature differences if the temperature is

changed only slowly. Switching the Peltier cooler from zero to 100%

immediately provides a lot of heat and, especially in the case of air-cooled

Peltier, the overall camera temperature can raise more than necessary. The

result is the chip temperature is higher in absolute numbers, because the hot-

side temperature is also higher. It takes long time before the hot side slowly

settles.

What is the best temperature for the CCD chip? The answer is simple – the

lower the better. But the minimum temperature is limited by the camera

construction. The G2 CCD cameras are equipped with two-stage cooler, which

can cool the chip up to 50 °C below ambient temperature with air cooling. But

it is not recommended to use maximum possible cooling. If the environment

conditions change, the camera may be unable to regulate the temperature if the

environment air temperature rises. Set the target temperature, which requires

approx. 85% of the cooling utilization. This provides enough room for e.g.

environment temperature changes etc.

The power supply voltage is also displayed in the “Cooling” tab. Especially

when the camera is powered from 12 V battery, this information can be used to

estimate when the battery should be replaced and recharged. Note that working

with less intensive cooling can significantly prolong the battery life.