[SOLVED] How To Tag Moon Phase Today Rotation

Watchface Design Expression Help
46

Still cant get the MoonAge formulae to match New Moon tables, available on various websites.

Here is my revised formula:

  • Derived from original ‘Simple()’ moon phase function - reference: Ben Daglish -)
  • Ben (G7)'s suggested use of: ((#DNOW#/1000)/86400, changed to scientific notation
  • Synodic month: 29.5306, based on correct rounding for 29.53058868
  • Lunar epoch date of: 1970 Jan 7 20:36 - reference: Lunar Perigee and Apogee Calculator)
  • Trig2() (beta code) shown for comparison, which is probably (errors not withstanding) more accurate

JulianDate:

base date:   J1721059.5 (1BCE-01-03 00:00:00.0 UTC) as J1

#NOW#
base date:   J2440587.5 (1970-01-01 00:00:00.0 UTC)

(#DNOW#/8.64e7+2440587.5)

(floor((#DNOW#/8.64e7+2440587.5)*10000)/10000)

Lunation: (lunar cycles, starting 1900)

lunar epoch: J2415020.0 (1899-12-31 12:00:00.0 UTC)

(floor(((70*365.2425)+(#DNOW#/8.64e7))/29.5306))

(floor(865.7791+(#DNOW#/8.64e7)/29.5306))

Moon Age:

lunar epoch: J2440594.358333 (1970-01-07 20:36:00.0 UTC)

(floor(
(((#DNOW#/1000)/86400+2440587.5-2440594.3583)%29.5306)
*100)/100)

(floor(
((#DNOW#/8.64e7-6.8583)%29.5306)
*100)/100)

(floor(((#DNOW#/8.64e7-6.8583)%29.5306)*100)/100)

1 Like
47

Additional revised syntax (as above)

Elongation:

Elongation = MoonAge x 12.1908

(((#DNOW#/8.64e7-6.8583)%29.5306)*12.1908)

Luminosity:

Luminosity = floor(( (1-cos( Elongation x 0.01745)) /2) x100) %

Output: ##.######

(floor(((1-cos(
(((#DNOW#/8.64e7-6.8583)%29.5306)*12.1908)
*0.01745))/2)*100))

(floor(((1-cos((((#DNOW#/8.64e7-6.8583)%29.5306)*12.1908)*0.01745))/2)*100))

In range: 20-100% (for icon)

(20+floor(((1-cos((((#DNOW#/8.64e7-6.8583)%29.5306)*12.1908)*0.01745))/2)*80))

Output: ##.0%

(floor((((1-cos(
(((#DNOW#/8.64e7-6.8583)%29.5306)*12.1908)
*0.01745))/2)*100)*10)/10)%

(floor((((1-cos((((#DNOW#/8.64e7-6.8583)%29.5306)*12.1908)*0.01745))/2)*100)*10)/10)%

1 Like
48

Does it match the tables with this modification now? It looks to be close, it is showing the same at Ben’s example above yours.

49

The number in black/red is Ben’s, included for comparison.

Yes, it is closer. But the trig2() function (combined output of 4 or more complex lunar cycles) is clearly superior. I am going to continue testing, and also complete the trig1() code. All three (and ‘Conway’) are listed on the Ben-Daglish.net website (see above).

For now, I would recommend to use my latest ‘Simplex’ formula.

Still a work-in-progress:

Update: Now with attitude (tilt) :innocent: This is just baseline, with seasonal variance still to be added.

4 Likes
50

Hi Ben, can you PLS check what I am doing wrong with my moon phase here?

51

@brbr123 i thing “moon mask 2.png” need 2 rounded mask
see mps.png at example here inspect: Facer - Thousands of FREE watch faces for Apple Watch, Samsung Gear S3, Huawei Watch, and more

1 Like
52

i don’t know how you guys keep those expressions straight. That’s just amazing!

53

Full moon is at 4/7/2020, 9:35pm.
It’s now 8:12pm(4/20) and your indicator
is showing 99.9% Waiting for 100% ; )
Bravo!
Thanks

1 Like