Subframe Selector process

[Alexis Jaldin]

Hello

Someone use SubframeSelector process?  Can  you teach me what parameters I have to use with Canon T5i Modified camera.

I found this tutorial,  but I'm still confuse

http://www.lightvortexastronomy.com/tutorial-pre-processing-calibrating-and-stacking-images-in-pixinsight.html

regards

Alexis

[John_Gill]

Hi,

These are the settings I use with my Celestron 8"EdgeHD Scope
Add Debayered files

System Parameters
Pixel Scale form nova.astronomy.net
(Canon 600d - 1.42 and with 0.7 reducer - 1.92

ISO      Gain     RN       DC*
-----------------------------------------------------------
100     8.79   15.5     0.146
200        4.40   8.1     0.081
400        2.19   4.8     0.048
800        1.12   3.2     0.039
1600     0.58   2.5     0.036
3200     0.29   2.2     0.041
6400     0.15   2.1     0.039
12800   0.07   1.9     0.035
--------------------------------------------------------
Gain = conversion factor, electrons per ADU
RN = readout noise, electrons r.m.s
DC* = electrons per pixel per second (bogus value, see below)
ISOs 6400 & 12800 are in fact digitally stretched ISO 3200

Camera Resolution - 16-bit
Scale unit - Arc seconds
Star detection
 - Star detection layers - 4
 - Noise reduction layers - 2
Measure

Most times I just use the defaults for the system parameters and I normally select the image with the highest SNR value.  If there are images with similar SNR values, then I select the image with the highest SNR and lowest Eccentricity value.  Some people use a fancy formula to work out the best value, but I don't bother too much with that

Look up
John

[Alexis Jaldin]

Thanks John for your reply!!!

I will check these parameters and try

 I will let you know

Thanks a lot

Alexis

[starwind]

I tested the sensor parameters for my T3i and these are what I get. The gains are diff from John's nos. I used Craig Stark's method described here: https://www.cloudynights.com/articles/cat/column/fishing-for-photons/signal-to-noise-part-3-measuring-your-camera-r1929 Also verified with PIs BasicCCDParameters Script

ISO    Gain e/ADU   Read Noise DN   Read Noise e-   Saturation e-   DR stops   Max ADU
---      ----------      -----------------   -------------      --------------    ----------  ----------
100    2.07             6.8                    14.1                24828            10.8         14043
200    1.07             7.1                    7.6                14747            10.9         15831
400    0.54             8.6                    4.6                7483             10.7     15831
800    0.28             11.7                3.2                3812              10.2     15831
1600  0.14             18.7                2.6                1941              9.5             15831
3200  0.07             33.1                2.4                1003             8.7             15832