Automatic adjustment of the LED (QHY-174-GPS)

Jean-Francois
Posts: 360
Joined: Sun Oct 13, 2019 10:52 am
Location: Germany

Re: Automatic adjustment of the LED (QHY-174-GPS)

#41

Post by Jean-Francois »

Hello Hiroyuki ,

For the 16 bit and all other settings similar to your test ...

[ms] Cal_Start Cal_End Exp. LED-time Delta SC_Start SC_End
================================================================================
3 752885 4192 3.00 -9.983 12.983 752750 4190
4 677916 4192 4.00 -8.983 12.983 677754 4190
5 602934 4192 5.00 -7.983 12.983 602757 4190
6 527961 4192 6.00 -6.984 12.984 527761 4190
7 452984 4192 7.00 -5.984 12.984 452765 4190
8 378009 4192 8.00 -4.984 12.984 377769 4190
9 303033 4192 9.00 -3.985 12.985 302772 4190
10 228056 4192 10.00 -2.985 12.985 227776 4190
11 153081 4192 11.00 -1.985 12.985 152780 4190
12 78101 4192 12.00 -0.985 12.985 77783 4190
13 10937 4192 13.00 -0.090 13.090 10939 4190
14 10937 4192 14.00 -0.090 14.090 10939 4190
15 10937 4192 15.00 -0.090 15.090 10939 4190

We can see the same LED-time results ... but that is not correct.
For these values, I use the "calib_qhy.py" script from a preceding message (1 June 2021).
Note that this script is a little bit modified, but not from me.

If I use an older different script ...
[ms] Cal_Start Cal_End Exp. LED-time Delta SC_Start SC_End
================================================================================
3 752887 975444 3.00 2.967 0.033 752750 975446
4 677916 975444 4.00 3.967 0.033 677754 975446
5 602934 975444 5.00 4.967 0.033 602757 975446
6 527961 975444 6.00 5.966 0.034 527761 975446
7 452984 975444 7.00 6.966 0.034 452765 975446
8 378009 975444 8.00 7.966 0.034 377769 975446
9 303033 975444 9.00 8.965 0.035 302772 975446
10 228056 975444 10.00 9.965 0.035 227776 975446
11 153081 975444 11.00 10.965 0.035 152780 975446
12 78102 975444 12.00 11.965 0.035 77783 975446
13 10937 982474 13.00 12.954 0.046 10939 982433
14 10937 1057450 14.00 13.954 0.046 10939 1057439
15 10937 1132426 15.00 14.953 0.047 10939 1132446

The LED-time and Delta are OK, but all the other values are wrong.

What is now the correct script and the correct results ?

I guess that the first script (calib_qhy.py) is correct, but the LED-time value calculation is wrong.
In the script, the LED-time is calculated = (Cal_End - Cal_Start)/75000 ... that was the old way to calculate, but with the new Start/End values, it is no more correct.

Other words ... I need to take some time for a summary of the different scripts.

For the LED-time calculation ... the values have no real use ... the real timing accuracy will come after comparaison with the GPS sensor.
All the values coming from the script are independent from the use of the GPS sensor. You can perform the LED calibration without the GPS sensor.

Regards,
Jean-Francois

Note ... I have this week free ... so you have some chance that I will update the script soon :-)
watan_rockhand
Posts: 17
Joined: Sat Jun 27, 2020 11:20 am

Re: Automatic adjustment of the LED (QHY-174-GPS)

#42

Post by watan_rockhand »

Hello Jean,

Thank you for checking. I'm looking forward to the correct script.

Hiroyuki Watanabe
Post Reply