I'go got a fullhd (1980x1080) movie clip with background image and two text lines
all lines are horizontally centered one line should be vertically centered in first half of image and second line in the bottom half of image.
Here is the code
image_clip = ImageClip("background_image.png", duration=4)
one_text = TextClip("One text".encode('utf-8'), fontsize=250, color='MediumGoldenRod', font="Arial-Unicode-MS")
start_x = 1920/2 - one_text.size[0]/2
start_y = 1080/2 - one_text.size[1] - 100
character_word = one_text.set_pos(('center','center')).set_position((start_x, start_y))
two_text = TextClip("Two Text".encode('utf-8'), fontsize=250, color='MediumGoldenRod', font="Arial-Unicode-MS")
start_x = 1920/2 - two_text.size[0]/2
start_y = 1080/2 - two_text.size[1] - 100
character_word = two_text.set_pos(('center','center')).set_position((start_x, start_y))
current_clip = CompositeVideoClip([image_clip,one_text,two_text])
My thoughts that there is something with textclip's relative positions.