Sensor temperature: is optimizing / scaling of frames possible?

[Peter S]

Hello again,

as I am using a non cooled system (DSLR) the sensor temperature rises significantly when taking several frames (up to a difference of 20 C).

I understand when choosing  the option "optimizing" the duration of the (master dark) frame is scaled to that of a flat.
But when taking frames (lights, darks) of identical duration this doesn't help regarding noise related to rising temperature, from frame to frame and during each frame.

Is there a way to scale frames of identical exp. time in relation to sensor temperature = rising noise

..."evaluate noise" ?
... by fits header ?

Peter

[bulrichl]

PixInsight's dark frame optimization uses neither exposure time nor sensor temperature. It scales the MasterDark minimizing the noise in the calibrated light frame, see https://pixinsight.com/forum/index.php?topic=8839.0 In this way both a changing temperature of the light frames and different exposure time is compensated.

However, it is advisable to capture the dark frames at the same exposure time as the light frames and at constant sensor temperature, close to that of the light frames. My experience (Canon 600D) is that the sensor temperature rapidly stabilizes after 5 - 6 exposure if short pauses (some seconds) between frames are used and the ambient temperature is nearly constant.

With cameras that have no or low "amp glow", it is recommendable to use dark frame compensation. You will have to try which approach gives the best calibration result.

The criterion for the best calibration result is not the full removal of hot pixels. It is normal that some hot pixels remain after calibration. These shall be removed by applying CosmeticCorrection.

Bernd