Sketchup? sounds like an edible condiment for kids.

as opposed to an inedible condiment? I meant an edible paint.

Sketchup

I use Sketchup but've never scaled anything in it. /not helpful :( Maybe some useful info in this Sketchup help forum thread?

To scale it? Uh, most Sketchup features involve a control key and a mouse movement and scaling is just a ... one of those, and pull until it's the right size.

Damned if I know which one, though.

Well, I had to wait till I got back to the office, but somebody showed me. My observation about mecha from this incident: needs moar architects!

How do you do it, pie=3?

Well, first you import the jpeg, then you measure a known distance on the image. In my case, I knew a block face was 431' long. I measured it on the imported image and found out its size in sketchup. Divide the real world size (in my example, 431') by the measured size in sketchup (65') and you have the ratio you want to scale to (in this example, (6.63 approx). Then you take the scale tool and click a handle, activating that little data input window at the lower right corner. Input the scale factor (6.63) and viola! The jpeg is now scaled to real world dimensions. It's a little more cumbersome than scaling in CAD, but not so bad once you get the hang of it.

Coolness galore - doesn't sound too horribly involved. So you divide what it should be by what it is to get the scale factor. I think I may have that scratched somewhere on one of my cheat sheets for CAD - like if we got a dwg from another office and it came in all wonky, we'd have to scale it. Good to know it works with jpegs too! Thanks, pie!