I think it's a human thing, not a blind thing. Even before I went blind I pictured what the radio DJs looked like.

Been totally blind for 20 or 22 years now. And I don’t do this. Effectively born blind comparatively to most people on this thread I see mostly only low vision folks comment here and not totals. I think it’s quite different with us totals

Went completely blind seven years ago, totally understand what you’re talking about, do this all the time.

I was born blind so I don't have experiences quite like this. However when I hear things I tend to kind of ... anthropomorphize them, for lack of a better term. And I associate them with particular textures. And of course, smell is a universal neumonic for everyone, which tends to build pictures or visualizations in my head.

Sometimes when laying on bed with my eyes closed I vision the designs of the old tin ceilings. And when my eyes are closed at other times, when there is a loud noise like a door closing or a book dropped or someone talks, I see a design of lights like the designs fireworks make, not the starbursts but the circle or hearts they make in the show, usually in red or blue. My doctor's say my brain is trying to see something that my brain remembered from the past.
Edit for spelling

I definitely find myself visualising and imaginging more to fill in the blanks to the world around me. When what I want to imagine has a very funcdtional purpose, like how to move my head to line up with the medical imaging equpment at my specialist's office, I visualise a vector from calculus that goes through the front of my eye to the back of my skull, iit's apparently quite effective because the techs have commented on how quickly it goes for me compared to their other patients.

When I'm descending stairs where I'm worried about losing my balance or falling, I'll turn the whole area into what I describe as a computer rendering of it so I keep focused. Like today, it's very bright out which makes it hard for me to see, so even on the back steps in my own back yard I feel the need to focus like this. Visualising the physics or mechanics of the situation keeps my brain from panicking at the absence of depth perception or functional sight when it's also worried about me getting hurt.

I imagine things with zero colours because I can only really distinguish light and dark and was totally blind since birth. But since you asked about imagination I have a kind of unique process.

I think about imagination like a puzzle. I have to build each piece separately and then put them all together. If you talked about a caucasian man with neck scars and tattoos, I would first picture his height and weight, then place the scars, then place the tattoos.

I do the same but sometimes it's way off about a person's hair for example because I have some vision and trust what I see.
What doesn't work is to explain a route or specific space in our neighbourhood to someone sighted. My SO really doesn't get it when I describe things I come across explaining a route or place. He really wants to though.

Yup I do it constantly. I thought the lid on my manual coffee grinder was a medium grey. Turns out it's completely clear. I based it largely off texture. I think it might play a little into my synesthesia

I have a friend. I thought he was black, and years later I found out he was white.

No experience of colour, so not in that regard. I do visualize in the sense of imagining things in space, but it's very abstract, just the form.

I have some vision but poor memory and I do this all the time. People never look like I imagine heh