June 3rd, 2022, 9:52 p.m. local time
I was fortunate these past two nights to have nearly identical and ideal evening conditions for sky observation, a high rarity. Last night, the Moon was at 9% illumination, and tonight it was at 15%.
When the Moon’s crescent is this thin, it actually becomes difficult to gauge the proper ISO and exposure settings. At 9% I used 1/8 second exposure in NightCap, and tonight I “halved” that for 1/16 second. If I had to guess, the Moon’s brightness increases nearly exponentially night after night as it approaches Full,; from experience 1/500 may be necessary in just a few days. If the skies remain as clear as they have been throughout the weekend, we will get to track the nightly reduction in exposure.
Constellation-wise, the Moon is leaving Gemini and entering Leo.
- 127mm Mak-Cass telescope
- 23mm eyepiece
- No eyepiece filter
- iPhone XS
- Smartphone telescope eyepiece adapter
- Nightcap app on iPhone
- 1/16 sec exposure
- ISO 24
- Focal length: 4mm
- Minor touchups in PaintShop Pro and AfterShot Pro