Bands of green airglow in the northern sky through the area of the two Dippers (Big and Little), on a June night. This was from Red Rock Canyon road in Waterton Lakes National Park, June 3, 2021. Clouds coming in add the glows on the stars. The Big Dipper is at top; the Little Dipper is at right. All of Ursa Major is visible above the peak. This is a single tracked 2-minute exposure with the MSM Tracker, and 20mm Sigma Art lens at f/2.8 adapted to the Canon EOS Ra at ISO 1600.
A portrait of the Big Dipper and Little Dipper high in the northern spring sky on a moonlit April night. Polaris is at lower left at the end of the handle of the Little Dipper. This is a stack of 4 x 1-minute exposures at f/2.8 with the Sigma 24mm Art lens adapted to the Canon EOS Ra at ISO 400, blended with a single image taken through an Alyn Wallace/Kase StarGlow filter plus an exposure taken through a Tiffen 6-point Star filter for added effect. Filter layers blended in with Lighten mode and masked to just the stars to prevent them from affecting the background sky illumination and uniformity. Taken April 20, 2021 from Dinosaur Provincial Park with the camera on the Star Adventurer 2i tracker with the quarter Moon off frame at top.
A 360° all-sky panorama of the northern spring sky with the Milky Way as absent from the sky as it can get for the year and from my latitude of 51° N. I shot this April 14/15, 2021 about 12:30 to 1 am MDT with the North Galactic Pole (NGP) in Coma Berenices due south and as high as it gets. So we are looking up out of the plane of the Galaxy, placing the band of the Milky Way along the horizon, visible here only as an arc low across the north at top, where it is obscured by the glow of Northern Lights that appeared this night. South is at bottom; north at top. West is to the right; east to the left. Zenith is at centre. I have added labels to this version. The Big Dipper is directly overhead at the zenith in the centre of the image. Polaris is above centre high in the north, close to the North Celestial Pole (NCP). Arcturus is the brightest star in the spring skly, and is here below centre and below the handle of the Dipper. Spica is at bottom low in the south. Castor and Pollux in Gemini are low in the west, the last of the winter stars setting. Capella in Auriga is at top right in the northwest, circumpolar from my latitude. Regulus in Leo is at bottom right high in the southwest. Flanking Leo are the naked-eye star clusters Melotte 111 (east, left, of Leo) in Coma Berenices, and M44, the Beehive (west, right, of Leo) in Cancer. Vega and Deneb are rising in the east at left, heralding the arrival of the summer stars. The head of Scorpius is just rising low in the southeast at bottom left, but Antares had not yet risen. While the aurora is prominent there was very little airglow banding apparent this night. It was a very clear transparent night. I shot this for book illustrations. This is a multi-segment panorama made of 24 segments (3 tiers of 8 each) for the sky, all tracked on the Star Adventurer 2i tracker, blended with a tier of 8 segments, untracked for the ground, masked in and aligned to the tracked segments. All were 45-second exposures at f/2.8 with the Sigma 24mm Art lens on the Nikon D750 at ISO 1600. Stitching was with PTGui which required a lot of tedious manual assigning of control points in adjacent images to get sky segments to align. It did not perform well automatically for this scene. And finding matching stars was tough as the spring sky contains so few bright stars and notable patterns to match up. The original is 15,000 pixels square.
