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 Notes - Session 218 (2007-10-02)

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Bullet TPoint Mapping Run (2007-10-02)
 
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Goto Images from 2007-10-02

TPoint Mapping Run (2007-10-02)

A TPoint mapping run was conducted comprising xx mapped points, using an automated script  (Time to complete xx minutes).

Raw Points - RMS  7.0 arc min (420 arc secs )
Image
# Term Value Sigma S/N
 
 

 
 

TPoint fit (2 terms) - RMS 5.9 arc min (356 arc secs)
Image
# Term Value Sigma S/N
1 IH -74.8 41.5 1.8
2 ID 212.5 34.8 6.1

2 terms :
- Index Error HA, 
- Index Error Dec
 

TPoint fit (6 terms) - RMS 5.2 arc mins (313 arc secs)
Image
1 IH -200.4 414.8 0.5
2 ID 398.0 42.2 9.4
3 NP -32.0 227.1 0.1
4 CH 111.6 435.5 0.3
5 ME -311.1 51.3 6.1
6 MA -56.2 40.4 1.4

6 basic (equatorial) terms

 
 

TPoint fit (8 terms) - RMS 2.0 arc mins (119 arc secs)

Significant improvement in S/N after removing 3 anomalous 
points and including Fork and Tube Flexure
Image
# Term Value Sigma S/N
1 IH -434.8 166.8 2.6
2 ID -218.7 33.5 6.5
3 NP -231.9 92.3 2.5
4 CH 429.7 175.8 2.4
5 ME 197.2 45.4 4.3
6 MA -54.9 16.2 3.4
7 TF -792.6 39.7 19.9
8 FO -212.6 49.2 4.3

8 terms:
6 basic (equatorial) terms 
2 flexure terms
  

TPoint fit (12 terms) -  RMS 1.6 arc min (96 arc secs) 
Low RMS value but poor S/N values 
Image
# Term Value Sigma S/N
1 IH -345.4 134.7 2.6
2 ID -35.9 182.0 0.2
3 NP -153.6 75.1 2.0
4 CH 310.0 142.5 2.2
5 ME -7.6 65.8 0.1
6 MA -62.1 13.1 4.8
7 TF -674.7 179.4 3.8
8 FO -71.5 45.3 1.6
9 HDSD1 -136.7 161.0 0.8
10 HHSH1 95.0 90.7 1.0
11 HDCD3 75.5 79.0 1.0
12 HDCD2 -42.3 93.3 0.5

12 terms : 
6 basic (equatorial) terms 
2 flexure terms
4 harmonic terms

Corresponding Polar Alignment Information 
************* AZIMUTH ************
MA: -62 seconds (-1.0 minutes).
Rotate axis East (clockwise).
For latitude 57.32°, the azimuth adjustment is 1.9 minutes.
Sigma=13.061

************* ALTITUDE ************
ME: -7 seconds (-0.1 minutes).
The polar axis should be lowered -7 seconds (-0.1 minutes).
Sigma=65.821

TPoint fit (8 terms) -  RMS 2.0 arc min (119 arc secs) 
Image
# Term Value Sigma S/N
1 IH -434.8 166.8 2.6
2 ID -218.7 33.5 6.5
3 NP -231.9 92.3 2.5
4 CH 429.7 175.8 2.4
5 ME 197.2 45.4 4.3
6 MA -54.9 16.2 3.4
7 TF -792.6 39.7 19.9
8 FO -212.6 49.2 4.3

8 terms : 
6 basic (equatorial) terms 
2 harmonic terms

 

Polar Alignment Information from 8 terms 
Northern Hemisphere

************* AZIMUTH ************
MA: -55 seconds (-0.9 minutes).
Rotate axis East (clockwise).
For latitude 57.32°, the azimuth adjustment is 1.7 minutes.
Sigma=16.180

************* ALTITUDE ************
ME: +197 seconds (+3.3 minutes).
The polar axis should be raised +197 seconds (+3.3 minutes).
Sigma=45.406

TPoint fit (11 terms) -  RMS 1.5 arc min (88 arc secs) 
Image
# Term Value Sigma S/N
1 IH -519.1 126.5 4.1
2 ID -373.8 28.5 13.1
3 NP -238.0 68.0 3.5
4 CH 499.3 132.9 3.8
5 ME 197.1 4.3
6 MA -55.0 3.4
7 TF -1024.5 36.1 28.4
8 FO -172.6 21.7 8.0
9 HHSH1 214.3 27.9 7.7
10 HDSH3 -28.9 13.0 2.2
11 HDSH5 -22.7 13.3 1.7

11 terms : 
6 basic (equatorial) terms 
2 flexure terms
3 Harmonic terms

 

Polar Alignment Information from 11 terms 
(MA/ME fixed based on 8 term solution)
Northern Hemisphere

************* AZIMUTH ************
MA: -55 seconds (-0.9 minutes).
Rotate axis East (clockwise).
For latitude 57.32°, the azimuth adjustment is 1.7 minutes.
Sigma=16.180

************* ALTITUDE ************
ME: +197 seconds (+3.3 minutes).
The polar axis should be raised +197 seconds (+3.3 minutes).
Sigma=45.406

  

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