The automated reduction of the Strömgren data required manual interaction only at the top control level; The average exposure for the Be data is one second, the minimum exposure time allowed by the JKT. However the brighter objects still saturate the CCD, to over come this problem the telescope requires defocusing, spreading the same amount of radiation over a much larger number of CCD pixels and thus stopping the effect. This method causes the stellar PSF to appear torus like in shape, with two disconnected bright areas at the edge of the detection. The source finding software interprets this as two distinct objects which in turn contaminates the photometry code. To overcome this the PL is instructed to operate using large aperture photometry, this encompassed “both” sources and processed them as one. The problem of defocusing will not effect the LT, the telescope will remain focused at all times and employ neutral density filters to stop saturation.
The Be stars observed are, in many cases, so bright as to be the only object visible
on the FITS frame. To allow a world co-ordinate system to be set there must be a
minimum of three stars which can be matched with the astrometric catalogue.
Therefore the WCS routines are unable to operate and rely on the pointing recorded
by the JKT, as already discussed the JKT pointing is severely disrupted and so
the WCS imparted will not be accurate. The WCS of the standard star frames is
however not in jeopardy. The design specifications of the LT require it to have pointing
accurate to 
2”, so this problem will not occur. The reason a WCS is required, in
this case, is to identify the object star in the frame, however the correct star was
easily identifiable as it is always the brightest object on the frame. If this is not the
case more stars can be observed, before saturation, to allow the WCS software to
operate.
Transformation of the reduced instrumental magnitudes to the standard Strömgren system was carried out following the procedures described by Gronbech et al. (1976) and Fabregat (2001), which minimise the following equations to determine the coefficients on a per night per colour basis;
| V | = A + B(b - y)st + yinst | (6.12) |
| (b - y)st | = C + D(b - y)inst | (6.13) |
| m1,st | = E + Fm1,inst + J(b - y)st | (6.14) |
| c1,st | = G + Hc1,inst + J(b - y)st | (6.15) |
 st | = a + binst | (6.16) |
band standards observed on the second night were corrupted and this necessitated their
substitution.
| Night | A | B | C | D | E | F | G | H | I | J | a | b
|
| 24 April | -0.0235 | 0.1633 | 0.0216 | 1.0643 | 0.0510 | 0.6059 | 0.0082 | 0.8785 | -0.1818 | -0.2365 | 1.0164 | 0.5414 |
| Errors | ±0.0113 | ±0.0305 | ±0.0098 | ±0.0288 | ±0.0432 | ±0.2470 | ±0.0624 | ±0.0812 | ±0.1364 | ±0.1433 | ±0.1009 | ±0.2161 |
| 25 April | -0.0150 | -0.2427 | 0.0189 | 0.9465 | -0.0069 | 0.9593 | 0.0229 | 1.0325 | -0.1929 | 0.1898 | 1.0164 | 0.5414 |
| Errors | ±0.0043 | ±0.0299 | ±0.0066 | ±0.0292 | ±0.01361 | ±0.0899 | ±0.0506 | ±0.0820 | ±0.1698 | ±0.0724 | ±0.1009 | ±0.2161 |
| Table 6.1: | The coefficients used to transform the Strömgren instrumental system to the standard Strömgren system. |
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