A photon is influenced of all gravitation gtot from every direction and the proportion of time * acceleration =v bend in the direction of strongest sum of field. This mean the deviation is much bigger than a hypothetic materia particle, even tough the magnitude is same. Since all colors bend equally (no dispersion), it follows that bending use a proportion of the photons energy (color). When passing a celestial body (ies) a perpendicular speed v=(sigma)g*t iis added depending on a body of gravitational constant µ and closest fly by distance r as follows v=2*µ/(c*r) where c is speed of light. The angle of curving (from - infinity to +infinity) a=arcsin(v/(c-v)). Electromagnetic energy transformed to kinetic momentum E*c is (delta)E/E=2*v/c where E=c*hi/(lambda). hi is my (indifferent) Planck constant 6,22*10^-34 Js and (lambda) the wavelength (color). The "lost" energy(decay) (delta)E=4*µ*hi/(c*r*(lambda)). The energy is "lost" quant by quant n*hi=2*v/(lambda), and the bend is stepped n steps, for weak gravity/long wavelength even distinguishable. Total redshift z is the sum of 4*µ/(c^2*r) regardless of direction.

Calculation ex. The volume of a r=13,5*10^9 ly universe can fit 2,2*10^12 galaxies 3,3*10^6 ly apart. Looking trough a r=13*10^9 ly and 13*10^9 ly long cylinder , it is having 1,06*10^12 galaxies of 1,2*10^31 m3/s2 (90 billion sun masses ). Randomly dispersed average distance from centerline is 8,2*10^25m giving average of 500 simulated z=8,6*10¨-12 times 1,06*10^12 give redshift about 9. Reminding me of something I've read. The distances r,l,d are assumed but their ratio hold.

For shorter stints or distances s=c/t the redshift is z=gtot*t/c where gtot is sum of all gravitation from all directions. Using 21.century celestial masses Mi that are 1,13 times mainstream masses and mn mass of nucleon 1,671*10^-27kg

Formulas can be written (delta)E/E=Mi*mn*c*t/(2*r¨2) and (delta)E/t=Mi*mn*c^2/(2*r¨2*(lambda)) =gtot*hi/(lambda). Close to planets gtot values are very different from classic g (mainstream). Here a few picked values from earth altitudes for using in calculating photon decay onboard satellites.

Altitude over sea level 0km 15,92m/s2 10km 15,82m/s2 20km15,73m/s2 50km15,48m/s2 100km15,11m/s2 200km14,45m/s2 300km13,86m/s2 400km13,32m/s2 500km12,82m/s2 1000km10,77m/s2 2000km8,02m/s2 5000km4,12m/s2 10000km1,936m/s2 20000km0,736m/s2 30000km0,385m/s2. For higher altitudes gtot=1,27*classic g +0,0075m/s2 for sun.

For the moon I have not calculated, but rough comparisons surprised me by suggesting proportionally same size heavy core as earths. This would mean that moon is a miniature of earth with high altitude g=1,27*classic.