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[ATM] Can Foucault Results Indicate Astigmatism?

Is the Foucault test able to detect astigmatism, and if so, what would 
indicate it's presence?  I don't think I have any, and am nearly done with 
my first mirror.  Ronchi tests do not indicate any S shaped lines in any 
mirror orientation, 0, 90, 120, 180, 270.  I am using TEX and Foucault Test 
Analysis 1c/Reifke, and they both indicate that I am at 1/8 or better and 
0.96 Strehl, using a three zone mask.  Included in this message are the TEX 
results from testing at ywo radii, 0 and 90 degrees.  How would I interpret 
this data to indicate the presence or absence of any astigmatism?

Thanks to the list for the earlier advice, once I digested that advice, sat 
down at the library and read parts of Texereau, edition 1, and actually 
could see the mirror shape changing in response to specific applications of 
the lap, things started falling into place.

Thanks,  Kurt
Nixa, MO

	TEXEREAU MIRROR TEST SHEET

            Comments: Kurt's 6" f7.5    Optical diameter: 5.9
   Readings per zone: 3
Radius of curvature: 87.25
                 f/D:  7.39
    Diffraction disc: 0.000194848

  1 ZONE                1          2          3
  2 h(x)              1.7032     2.4087     2.9500
  3 h(m)              0.8516     2.0559     2.6793
  4 hm**2/R           0.0083     0.0484     0.0823
  5 hm/4f             0.0049     0.0118     0.0154
  6 D1                0.2087     0.2360     0.2867
  7 D2                0.1840     0.2080     0.2653
  8 D12               0.1963     0.2220     0.2760
  9 D12 -  0.1850     0.0114     0.0370     0.0910
10 Lamda c           0.0031    -0.0114     0.0088
11 Lamda f * 1e5       1.49     -13.44      13.44
12 Lamda f / rho      0.077     -0.690      0.690
13 u * 1E6            -0.34       3.08      -3.08
14 Wavefront           0.00       1.92       0.00
	Reference parabola: y = 0.0871651 * x**2 + -0.835159
	passing through (  1.70,  0.00) and (  2.95,  0.00)

Maximum wavefront error = 1 / 11.2 wave at zone 2

Results for individual sets of readings:
	Reading set 1: 1 / 14.0 lamda, Max Trans Abberation=0.55
	Reading set 2: 1 / 12.5 lamda, Max Trans Abberation=0.62
	Reading set 3: 1 / 14.0 lamda, Max Trans Abberation=0.55
	Reading set 4: 1 / 10.2 lamda, Max Trans Abberation=0.76
	Reading set 5: 1 /  8.7 lamda, Max Trans Abberation=0.90
	Reading set 6: 1 / 10.2 lamda, Max Trans Abberation=0.76



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