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---1.08, 1.06, 1.07
Integration time (s)---1800, 1800, 1200
Pixel scale (arcsec)---1.134, 1.134, 1.134

# Thu 15:09:26 30-May-2002
begin	BFIT
	status	0	(Solution converged)
	variance	4.731225E-4
	stdeviation	0.02175138
	avsqerror	4.716113E-4
	averror		0.02171661
	avsqscatter	2.930113E-4
	avscatter	0.01711757
	chisqr		1.003204
	msq		4.336956E-4
	rms		0.02082536
	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
		0.2522084
		-0.022
		0.
	errors	4
		0.
		0.003991939
		0.
		0.

# Thu 15:09:48 30-May-2002
begin	VFIT
	status	0	(Solution converged)
	variance	3.186176E-4
	stdeviation	0.01784986
	avsqerror	3.344381E-4
	averror		0.01828765
	avsqscatter	1.270007E-4
	avscatter	0.01126946
	chisqr		0.9526951
	msq		2.958592E-4
	rms		0.01720056
	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
		0.137418
		0.045
		0.
	errors	4
		0.
		0.002664746
		0.
		0.

# Thu 11:03:34 06-Jun-2002
begin	UFIT
	status	0	(Solution converged)
	variance	0.002012777
	stdeviation	0.04486399
	avsqerror	0.002012014
	averror		0.04485548
	avsqscatter	0.001132588
	avscatter	0.03365395
	chisqr		1.000379
	msq		0.001925265
	rms		0.04387784
	reference	m1
	fitting		(UB+BV+V)+u1+u2*X1+u3*BV+u4*BV*X1
	weights		photometric
	parameters	4
		u1	(fit)
		u2	(constant)
		u3	(constant)
		u4	(constant)
	derivatives	4
		0.1
		0.1
		0.1
		0.1
	values	4
		5.285
		0.598
		-0.177
		0.
	errors	4
		0.003
		0.
		0.
		0.