The following calibration format can be used directly in 
IRAF.digiphot.photcal.invertfit. The instrumental magnitudes
mU, mB, and mV are -2.5*log(counts/s)+25.

For the these images, the average parameters for UBV are the following:
Airmass---1.25, 1.06, 1.17
Integration time (s)---1800, 1800, 1200
Pixel scale (arcsec)---1.134, 1.134, 1.134

# Thu 15:05:41 30-May-2002
begin	BFIT
	status	0	(Solution converged)
	variance	3.136018E-4
	stdeviation	0.01770881
	avsqerror	3.120925E-4
	averror		0.01766614
	avsqscatter	1.273389E-4
	avscatter	0.01128445
	chisqr		1.004836
	msq		3.053492E-4
	rms		0.01747424
	reference	mB
	fitting		(BV+V)+b1+b2*XB+b3*BV+b4*BV*XB
	weights		photometric
	parameters	4
		b1	(constant)
		b2	(fit)
		b3	(constant)
		b4	(constant)
	derivatives	4
		0.1
		0.1
		0.1
		0.1
	values	4
		3.445
		0.2458613
		-0.022
		0.
	errors	4
		0.
		0.001528249
		0.
		0.

# Thu 15:06:44 30-May-2002
begin	VFIT
	status	0	(Solution converged)
	variance	3.555940E-4
	stdeviation	0.0188572
	avsqerror	3.599697E-4
	averror		0.01897287
	avsqscatter	1.463815E-4
	avscatter	0.01209882
	chisqr		0.9878443
	msq		3.469210E-4
	rms		0.01862581
	reference	mV
	fitting		V+v1+v2*XV+v3*BV+v4*BV*XV
	weights		photometric
	parameters	4
		v1	(constant)
		v2	(fit)
		v3	(constant)
		v4	(constant)
	derivatives	4
		0.1
		0.1
		0.1
		0.1
	values	4
		3.017
		0.128904
		0.045
		0.
	errors	4
		0.
		0.001483865
		0.
		0.

# Thu 13:27:34 11-Jul-2002
begin	UFIT
	status	0	(Solution converged)
	variance	0.003931091
	stdeviation	0.06269842
	avsqerror	0.003929554
	averror		0.06268615
	avsqscatter	0.00372847
	avscatter	0.0610612
	chisqr		1.000391
	msq		0.003743897
	rms		0.06118739
	reference	mU
	fitting		(UB+BV+V)+u1+u2*XU+u3*BV+u4*UB*XU
	weights		photometric
	parameters	4
		u1	(fit)
		u2	(constant)
		u3	(constant)
		u4	(constant)
	derivatives	4
		0.1
		0.1
		0.1
		0.1
	values	4
		5.267
		0.472
		-0.125
		0.
	errors	4
		0.01
		0.
		0.
		0.