My dad knew he hadn't much time so it probably helped. If your mother has a unique story (war, achievement, migration...) maybe she'll be inclined to tell it. Also, it's easier to talk about others, so you could ask her about her parents. Then you could switch to her.
I'll emphasize that like anyone born before smartphones, she may wish she had more pictures and videos from decades ago. Assuming that, she may understand your point of view and accept being the subject.
As for the production, I found that having a couple of smartphones were good enough for me. You do want to have backup capture. I wish I had had a better mic setup to record both voices with proper gain but modern smartphones are pretty good. Then I used Kdenlive for putting things together.
I'm sorry to hear that. May I suggest that you try and record a small session with specific questions? From my small experience with family members suffering from this, they may be able to talk to a small extent about some subjects (not the ones you want but still talk). It'll probably be ungrateful at first, but it may be better than nothing down the road.
To be honest, I'm still under shock but what I feel is that I wish I had time to ask everything. The thing is you don't know what will resonate with them, so you have to ask a lot to have something to work with and connect to.
This sounds like a pretty good way to do it. I'd still recommend some video recordings because facial expressions and gesture language are something I want to remember.
My only plan is to share with family members and ensure records don't get lost.
I'm very sorry for your loss. I'm very fortunate that he didn't have dementia so he could articulate some thoughts. I hope your story will push others to act before it's too late.
My dad knew he hadn't much time so it probably helped. If your mother has a unique story (war, achievement, migration...) maybe she'll be inclined to tell it. Also, it's easier to talk about others, so you could ask her about her parents. Then you could switch to her.
I hope it helps.