# The ASI294MM-Pro

##### Properties of my ASI294MM-Pro

For an upcoming Echelle spectrograph I bought a new detector, an ASI294MM-Pro. This is my first CMOS chip. I want to present my observations on this detector to show the effect of technical progress.

Please find a more extensive evaluation of the asi294mm-pro at Christian Buil's site.

The ASI294 is operated under Linux on an INDI server. indi_asi_ccd is used as the driver. The client is ccdciel. Gain was 200, offset 8. I have reproduced all measurements also with my old Atik460EX with the driver indi_atik_ccd.

###### Bias

I took 30 bias shots with an exposure time of 0.00032 sec at a temperature of -20°C. The arithmetic mean of these frames give the particular meanbias. The results in the meanbiases and the particular single biasframe bias004.fits are

Frame ASI294 Atik460
Num Pixall116943686045051
Meanmeanbias561320
Std Devmeanbias3.93.2
Meanbias0004572320
Std devbias00041617

I show you the 10th column from the right border.

##### Darks

I took 30 dark frames of 600s exposure time at a temperature of -20°C with my ASI and 23 with my ATIK. 29 rsp. 22 of them were mean averaged and also also a median average of these frames was computed. See the meandark:

There is a light in the dark to better find your way home at night.

The two mean darks are not very different.

Property ASI294 Atik460
Mean 570 321
Std Dev 41 104
ADU ≤ xxx ≤400: 0px ≤300: 0px
ADU ≥ xxxx ≥1200: 735px ≥1000: 463px

I made a simple data frame to see what the unwanted lantern does to weak data. My weak signal is 4096 ADU all over the chip. $\mathrm{sim\_data} = 4096 + \mathrm{remaining\_dark}$ $\mathrm{pure\_data} = \mathrm{sim\_data} - \mathrm{meandark}$ This simple data reduction removes the glow of the amplifier leaving some noise that comes with every signal. See characteristics of the resulting frame $$\mathrm{pure\_data}$$ in the table below and following a plot of the 10th rightmost column in $$\mathrm{sim\_data}$$ and $$\mathrm{pure\_data}$$ from the asi cam. At last 10th last column of $$\mathrm{pure\_data}$$ from cmos vs. ccd.

Property ASI294 Atik460
mean 4087.020 4095.983
median 4086.483 4095.958
std dev 31.66 19.59

-> comparison of flatfields.