Ptolemaeus-Alphonsus-Azarchel-Purbach-Regiomontanus-Walther
Reprocess of video taken 11/25/2017 using a 3x drizzle process in AutoStakkert!2.
This is an area I have photographed several times over the years. It is a view along the terminator about 8 days after new moon, one day past first quarter. I took the video for this image November 25, 2017.
Many noteworthy craters appear in this image, and they are all familiar friends to those who examine the moon. Two trios of larger craters dominate the image. The upper trio includes the very large Ptolemaeus, Alphonsus, and Arzachel (at center). The lower trio are, from the top, Purbach, Regiomontanus, and Walther (bottom, right of center).
The high ridges where Purbach, LaCaille and Blanchinus craters intersect are responsible for the famous "Lunar X" visual feature. For a few hours, when sunlight first touches these ridges at the First Quarter Moon phase, they shine brightly against the dark, shadowy terminator in the shape of a distinctive "X".
Best 80% of 650 video frames. Preprocessing with PIPP to stretch whites to 90%, and crop to the area shown. Stacking with AutoStakkert!2 (3x drizzle), post-processing in Photoshop CC 2018.
ZWO ASI290mm camera, Optolong IR Pass (685nm) filter, Explore Scientific ED 80 APO f/6 480mm refractor, Celestron Advanced VX EQ mount.
Ptolemaeus-Alphonsus-Azarchel-Purbach-Regiomontanus-Walther
Reprocess of video taken 11/25/2017 using a 3x drizzle process in AutoStakkert!2.
This is an area I have photographed several times over the years. It is a view along the terminator about 8 days after new moon, one day past first quarter. I took the video for this image November 25, 2017.
Many noteworthy craters appear in this image, and they are all familiar friends to those who examine the moon. Two trios of larger craters dominate the image. The upper trio includes the very large Ptolemaeus, Alphonsus, and Arzachel (at center). The lower trio are, from the top, Purbach, Regiomontanus, and Walther (bottom, right of center).
The high ridges where Purbach, LaCaille and Blanchinus craters intersect are responsible for the famous "Lunar X" visual feature. For a few hours, when sunlight first touches these ridges at the First Quarter Moon phase, they shine brightly against the dark, shadowy terminator in the shape of a distinctive "X".
Best 80% of 650 video frames. Preprocessing with PIPP to stretch whites to 90%, and crop to the area shown. Stacking with AutoStakkert!2 (3x drizzle), post-processing in Photoshop CC 2018.
ZWO ASI290mm camera, Optolong IR Pass (685nm) filter, Explore Scientific ED 80 APO f/6 480mm refractor, Celestron Advanced VX EQ mount.