Takahashi BRC-250　Bitran BJ-41L
L10min.x12 R5min.(2x2)x2　G5min.(2x2)x2　B5min.(2x2)x2
Tokai TYPEIII filter　　LRGB

NGC5457 (M101　Galaxy in Ursa Major)
14h03m12.7s +54 21 12 Mag.(V)7.9 Dim' 28.8x26.9 SB14.9 SAB(rs)cd I