Is it permissible to take/own sunset/sunrise photos? Is there any difference between an image of the whole sun or partial sun?
You are bringing up a very good point. Although this is not known to many people, we are not allowed to draw or take pictures of the sun, as part of the prohibition not to make images in the heavens, even if the drawing is flat and not 3d. There are different opinions if one may make a picture of half a sun.
The poskim say that taking pictures is included in this, although it is questionable if the picture is developed by a goy. L’chatchila one should not take pictures of the sun, however it is permitted to take pictures of half the sun during sunrise or sunset.
Avodah Zara 43b, Rosh Ibid 3-5, Rambam Avodas Chochavim 3-11, Y:D 141-4, Taz ibid 13 , since the sun etc. are seen by us in a non-protruding manner in the sky . Shevet Halevi 7-134-7 permits a picture of a partial sun as this is not the normal way the sun looks, but not a partial moon. Avnei Yushfei 1-151-2, quoting shach ibid 25 ( end), Sarchei Teshuva ibid 38,that the Shach isn’t referring to half a moon. Regarding pictures of sunset see Halachically speaking vol.3-8 ftnt. 82 quoting R’ Y.Belski zt”l, and Am Hatorah 3-5 pg. 62 in the name of R’ N. Korelitz shlit”a.