It's not. The photos with the horizon visible are photos taken during the descent, whereas the photos with only ground visible were taken as landing was imminent (or after landing).
There is a photo on the page that shows the horizon from a landed position, that's the one he's referring to.
It links to, and is displayed, here; with no indication that it's an artist's take on what it would look like. It seems to be D. Mitchell's stitching work from this Venera-13 clear-filter panoramic transmission with added perspective from the color-filter panoramic transmissions.
I think the upper half of the photo with the horizon visible is some kind of artistic recreation. The original photos did not show the horizon.
It's not. The photos with the horizon visible are photos taken during the descent, whereas the photos with only ground visible were taken as landing was imminent (or after landing).
There is a photo on the page that shows the horizon from a landed position, that's the one he's referring to.
It links to, and is displayed, here; with no indication that it's an artist's take on what it would look like. It seems to be D. Mitchell's stitching work from this Venera-13 clear-filter panoramic transmission with added perspective from the color-filter panoramic transmissions.