El T7 anda en magnitud 4.1.........el Q4 en magnitud 4.3
T7
2004 Apr. 17.80 UT: m1=4.7, Dia.=3', DC=6... 25x141B...Yoshimi Nagai (Nagano, Japan) [Morris Method. Used 14.1cm B, Because low altitude and twilight. Data from the Tycho-2 catalog Johnson V magnitudes, and used correcting for atmospheric extinction.]
*2004 Apr. 18.38 UT: m1=4.0, Dia.=6', DC=7/8, Tail:>0.33 deg.in PA 260 deg... 5cm R, f/7 (10x)... Walter R.Robledo (Cordoba, Argentina)[out-out method, corrected for atmospheric extinction.].
*2004 Apr 19.37 UT: m1=4.1, Dia=6', DC=6, Tail ~15' at PA 245...7X50 B...David Marshall (Clapham, Christ Church, Barbados) [Coma appears elongated by 0.5' - 1' in direction of tail.]
*2004 Apr.19.38 UT: m1=4.5, Dia=5', DC=7...7x50B... Luis Mansilla (Laboulaye - Córdoba, Argentina) [Morris Method, naked eye: m=4.5]
Q4
*2004 Apr 19.44 UT: m1=4.3, Dia=13', DC=6, Tail=1 deg in PA 160 deg...10x50B...(Robert Hancock, Port Elliot, South Australia )
*2004 Apr 19.53 UT: m1=4.8, Dia=14.5', DC=7...8x40B...Andrew Pearce (Nedlands,Western Australia)[Tail visible 1.7 deg long in PA 148 deg]
*2004 Apr 20.00 UT: m1=5.0, Dia = 8', DC = 6, Tail = 1 deg in PA 150 deg to PA 170 deg ... 7x50 B ... Gustavo Enrique Ballan (Rosario, Argentina) [comet C/2001 Q4 very easily visible with binoculares; visual limiting magnitude = 5.2; instrumental limiting magnitude for stelar objects = 8.3; fan-shaped tail, covering a PA range from 150 deg to 170 deg; tail is longest and brightest at PA 150 deg, 1 deg long, 0.5 deg long at 170 deg; Morris method used]