Tuesday 7 March 2006

Oh, how I love Japanese electronics... (timing error issues)

Yep, it seems have a ~0.3 second timing devation again against other stations. Here's two messages I sent out in our tracking network today, summing up the issue:

-----
Hmmm,

I am starting to worry again. Since resuming my observational activities here at the new site, I seem to be some 0.25-0.3 second off in timing again. E.g. these two sets:

Lacrosse 5 Rk
STA AZ EL ASP XTRK deltaT Perr
( 1) 2420 78.35 66.69 108.86 0.00 -0.06 0.035 <-- Russell, 5 Mar
( 2) 2420 106.00 72.99 104.58 0.00 -0.06 0.041 <-- Russell, 5 Mar
( 3) 4353 324.85 79.48 80.67 0.02 -0.29 0.207 <-- me, 6 Mar
( 4) 4353 5.83 84.79 87.43 0.01 -0.33 0.237 <-- me, 6 Mar

Lacrosse 5:

STA AZ EL ASP XTRK deltaT Perr
( 1) 2701 231.94 31.12 39.72 0.01 -0.00 0.012 Mar 03
( 2) 2701 235.93 49.68 54.66 0.00 -0.02 0.008 Mar 03
( 3) 2701 236.19 50.53 55.39 0.00 0.00 0.003 Mar 03
( 4) 6226 325.33 24.24 96.83 0.00 -0.01 0.004 Mar 04
( 5) 6226 327.32 24.03 98.43 0.00 -0.02 0.006
( 6) 6226 328.97 23.82 99.76 0.01 0.01 0.008
( 7) 6226 333.11 23.20 103.11 0.02 0.04 0.017
( 8) 2018 165.10 15.25 59.66 0.00 -0.02 0.006
( 9) 2018 147.53 20.13 74.61 0.01 -0.05 0.016
(10) 2018 136.04 21.67 84.19 0.00 -0.06 0.018
(11) 2018 132.70 21.89 86.95 0.01 -0.06 0.019
(12) 2018 120.60 21.84 96.93 0.01 -0.02 0.008
(13) 710 147.36 37.57 83.08 0.01 -0.36 0.141
(14) 2018 98.36 18.25 115.52 0.00 -0.04 0.009
(15) 4353 242.78 47.55 52.67 0.01 -0.28 0.102 <-- me, Mar 04
(16) 4353 243.07 51.50 55.99 0.00 -0.30 0.119 <-- me, Mar 04

I did not alter anything in my camera settings this time, as far as I am aware of. I will re-check the GPS measurement of my new location, although I doubt a small error in that would lead to a 0.3s time difference...

- Marco :-/
-----

I just did a new GPS measurement on the courtyard. Got a good fix, and it yields the same coordinates with differences only in the second decimal of the arcseconds. So no problem there it seems.

Also checked the DCF77 radio-controled clock I use. It seems to be okay when I check it against my computer clock, which is synchronized each 5 minutes by an NSTP server.

So it must be the camera again, or the person pushing the camera button (me). Interestingly, it is again an ~0.3 second error, just as the last time such a deviation popped up, half a year ago. Oh, how I love Japanese electronics....

I realized I *did* alter my camera settings shortly in December, while taking night-time images of snow in Delft. But I changed them back to the old settings again afterwards, as far as I am aware of. Again: oh, how I love Japanese electronics... From now on I'll refrain from doing anything to the manual settings again.

Well, I guess I have to work with another empirical 0.3 seconds correction again from now on. By making such a correction to the datasets I reported the past two weeks, my data come quite in line with the other data again.

- Marco
-----

No comments: