I suggest that the notion that Dylan is using camera obscura for some of his recent work is highly unlikely. It is the wrong tool to use if one is working from photographs. It is not practical at all, especially if one considers the scale of Dylan's paintings.
One can call it "tracing" but I think that might be a bit insulting to the artist. Hockney makes a point to say, "Optics do not make marks."
I've spent a fair amount of time exploring the approaches that Dylan might be using. I think a projector is likely. Warhol was known to use a projector. Hockney includes a Warhol example in his book
Secret Knowledge. I think that another possibility is the use of camera lucida. Hockney did a series of portraits using this tool. It is quite different from camera obscura, and is particularly well suited to working from still images.
I have three different camera lucida tools that I was experimenting with in 2015 (I also have an overhead projector and an opaque projector). I did one experiment where I worked from a Josef Koudelka photograph that Dylan had based one of his paintings on. I used one of my camera lucida tools and I posted the results on Instagram a couple of months ago:
https://www.instagram.com/p/8bFnLWrexk/The scale of my drawing is fairly small, just a few inches across. But if I wanted to produce a work the size of Dylan's painting it would be fairly easy to adjust my process. I belong to a camera lucida club, and many members make large scale works. If I was going to work on a larger scale I'd be just as inclined to use my opaque projector.
As far as Dylan and
Tim's Vermeer, here's a few lines from a news story on the film: "We kept it a real secret," Jillette said in an interview during the festival. "No one knew anything. I think the only people who had a copy of the DVD were Bob Dylan and Jack White. That was the entire list."
From another:
Penn Jillette: "We throw the word genius around. Bob Dylan’s a genius. And Bob Dylan’s a genius because we don’t want to think that Bob Dylan is doing this stuff because he’s willing to work harder than we are. (Laughs) We’ve all seen Bob Dylan’s notebooks. We all know the thousands of hours he’s spent on stage. We all know that Bob Dylan isn’t known for his guitar playing, but he practices guitar playing thousands and thousands of hours. We tend to throw that word genius around to say we can’t do this so why don’t we just sit on our asses and watch TV. We also throw this other word around. Teller just said this beautiful thing last night: 'Obsession is a word lazy people use for determination.' (Laughs) I think that the people who are called geniuses are willing to keep that going because there’s something kind of prosaic at first blush about saying, 'Well, I just worked really hard.'"
I first wrote about Dylan, Hockney and camera obscura back in 2013:
http://swarmuth.blogspot.com/2013/03/ap ... dylan.html